GATOR1 complex subunit that inhibits TORC1 signaling during amino acid limitation and nutrient stress.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
|
GO:0034198
cellular response to amino acid starvation
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: Nprl2 participates in the response to amino-acid starvation.
Reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid starvation.
Supporting Evidence:
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0005096
GTPase activator activity
|
IBA
GO_REF:0000033 |
KEEP AS NON CORE |
Summary: GATOR1 has Rag GTPase GAP activity; Nprl2 is a GATOR1 subunit.
Reason: GTPase-activating activity is established for GATOR1 (RagA/B), so the IBA is reasonable for Nprl2 but not the primary focus.
Supporting Evidence:
PMID:23723238
GATOR1 has GTPase-activating protein (GAP) activity for RagA and RagB
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
|
|
GO:0005774
vacuolar membrane
|
IBA
GO_REF:0000033 |
MODIFY |
Summary: The vacuolar membrane term is yeast-specific; Drosophila data indicate lysosomal localization.
Reason: Replace vacuolar membrane with lysosome to match the Drosophila localization evidence.
Proposed replacements:
lysosome
Supporting Evidence:
PMID:24786828
Nprl2 and Nprl3 physically interact and are targeted to lysosomes and autolysosomes
|
|
GO:1990130
GATOR1 complex
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: Nprl2 is a core subunit of the GATOR1 complex.
Reason: UniProt annotates Nprl2 as a probable GATOR1 subcomplex component, supporting this complex membership.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
probable component of the GATOR1 subcomplex which is likely composed of Iml1, Nplr2 and Nplr3
file:genes/DROME/Nprl2/Nprl2-deep-research-falcon.md
Nprl2 is one of three core subunits of GATOR1 (with Iml1/DEPDC5 and Nprl3).
|
|
GO:0005737
cytoplasm
|
IEA
GO_REF:0000044 |
KEEP AS NON CORE |
Summary: Nprl2 localizes to the cytoplasm.
Reason: UniProt reports cytoplasmic localization.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
SUBCELLULAR LOCATION: Cytoplasm
|
|
GO:0005764
lysosome
|
IEA
GO_REF:0000044 |
KEEP AS NON CORE |
Summary: Nprl2 localizes to lysosomes under nutrient stress.
Reason: Lysosomal targeting is reported for Nprl2/Nprl3.
Supporting Evidence:
PMID:24786828
Nprl2 and Nprl3 physically interact and are targeted to lysosomes and autolysosomes
|
|
GO:0051301
cell division
|
IEA
GO_REF:0000043 |
MARK AS OVER ANNOTATED |
Summary: General cell division is too broad relative to the specific mitotic-to-meiotic transition role.
Reason: Evidence indicates a specific mitotic/meiotic transition control rather than broad cell division.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
down-regulate TORC1 to slow cellular metabolism and promote the mitotic/meiotic transition
|
|
GO:0051321
meiotic cell cycle
|
IEA
GO_REF:0000043 |
MODIFY |
Summary: Meiotic cell cycle is captured more precisely by germline mitotic-to-meiotic switching.
Reason: Use the more specific germline cell cycle switching term supported by ovarian cyst data.
Proposed replacements:
germline cell cycle switching, mitotic to meiotic cell cycle
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
down-regulate TORC1 to slow cellular metabolism and promote the mitotic/meiotic transition
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IEA
GO_REF:0000117 |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
|
|
GO:0034198
cellular response to amino acid starvation
|
NAS
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
ACCEPT |
Summary: Nprl2 participates in the response to amino-acid starvation.
Reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid starvation.
Supporting Evidence:
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:1904262
negative regulation of TORC1 signaling
|
NAS
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IMP
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
|
|
GO:0009267
cellular response to starvation
|
IMP
PMID:27672113 The GATOR1 Complex Regulates Metabolic Homeostasis and the R... |
KEEP AS NON CORE |
Summary: Starvation response is supported but primarily in the amino-acid limitation context.
Reason: Evidence supports amino-acid starvation response; the broader starvation term is acceptable but not core.
Supporting Evidence:
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
PMID:27672113
The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to Nutrient Stress in Drosophila melanogaster.
|
|
GO:0010898
positive regulation of triglyceride catabolic process
|
IMP
PMID:27672113 The GATOR1 Complex Regulates Metabolic Homeostasis and the R... |
MARK AS OVER ANNOTATED |
Summary: Nprl2 affects TAG storage, but direct positive regulation of triglyceride catabolism is not shown.
Reason: Reported phenotype is reduced TAG storage in mutants, which does not directly demonstrate increased triglyceride catabolism.
Supporting Evidence:
PMID:27672113
nprl2 and nprl3 mutant adults contain reduced amounts of stored TAG relative to wild-type animals
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IGI
PMID:27672113 The GATOR1 Complex Regulates Metabolic Homeostasis and the R... |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
PMID:27672113
The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to Nutrient Stress in Drosophila melanogaster.
|
|
GO:0051729
germline cell cycle switching, mitotic to meiotic cell cycle
|
IGI
PMID:25512509 TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entr... |
KEEP AS NON CORE |
Summary: Nprl2 promotes the mitotic-to-meiotic transition in germline cysts via TORC1 inhibition.
Reason: GATOR1 members down-regulate TORC1 to promote the mitotic/meiotic transition.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
down-regulate TORC1 to slow cellular metabolism and promote the mitotic/meiotic transition
PMID:25512509
TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entry and oocyte development in Drosophila.
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IMP
PMID:27672113 The GATOR1 Complex Regulates Metabolic Homeostasis and the R... |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
PMID:27672113
The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to Nutrient Stress in Drosophila melanogaster.
|
|
GO:0035859
Seh1-associated complex
|
IDA
PMID:27166823 The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lyso... |
MODIFY |
Summary: The SEA/GATOR complex term is broader than the specific GATOR1 complex membership.
Reason: Evidence supports GATOR1 subcomplex membership; use the specific GATOR1 complex term.
Proposed replacements:
GATOR1 complex
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
Component of the GATOR complex consisting of mio, Nup44A/Seh1, Im11, Nplr3, Nplr2, Wdr24, Wdr59 and Sec13
PMID:27166823
The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lysosome Function.
|
|
GO:1904262
negative regulation of TORC1 signaling
|
IGI
PMID:27166823 The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lyso... |
ACCEPT |
Summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid starvation.
Reason: Both UniProt and the starvation study describe Nprl2-mediated inhibition of TORC1 in response to amino-acid limitation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:24786828
Nprl2 and Nprl3 inhibit TORC1 signaling in the female germline in response to amino-acid starvation.
PMID:27166823
The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lysosome Function.
|
|
GO:1990130
GATOR1 complex
|
TAS
PMID:27166823 The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lyso... |
ACCEPT |
Summary: Nprl2 is a core subunit of the GATOR1 complex.
Reason: UniProt annotates Nprl2 as a probable GATOR1 subcomplex component, supporting this complex membership.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
probable component of the GATOR1 subcomplex which is likely composed of Iml1, Nplr2 and Nplr3
PMID:27166823
The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lysosome Function.
|
|
GO:0032007
negative regulation of TOR signaling
|
IMP
PMID:23723238 A Tumor suppressor complex with GAP activity for the Rag GTP... |
MODIFY |
Summary: This term is too general for the specific TORC1 inhibition shown for Nprl2.
Reason: Evidence supports inhibition of TORC1 specifically; replace with the TORC1-specific term.
Proposed replacements:
negative regulation of TORC1 signaling
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
functions as an inhibitor of the amino acid-sensing branch of the TORC1 signaling pathway
PMID:23723238
A Tumor suppressor complex with GAP activity for the Rag GTPases that signal amino acid sufficiency to mTORC1.
|
|
GO:0034198
cellular response to amino acid starvation
|
IMP
PMID:23723238 A Tumor suppressor complex with GAP activity for the Rag GTP... |
ACCEPT |
Summary: Nprl2 participates in the response to amino-acid starvation.
Reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid starvation.
Supporting Evidence:
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
PMID:23723238
A Tumor suppressor complex with GAP activity for the Rag GTPases that signal amino acid sufficiency to mTORC1.
|
|
GO:0007293
germarium-derived egg chamber formation
|
IGI
PMID:25512509 TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entr... |
MODIFY |
Summary: Evidence points to oogenesis/meiotic entry roles rather than the specific egg chamber formation term.
Reason: Use the broader oogenesis term supported by meiotic entry/oocyte development data.
Proposed replacements:
oogenesis
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
control meiotic entry and promote oocyte growth and development
PMID:25512509
TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entry and oocyte development in Drosophila.
|
|
GO:0005515
protein binding
|
IPI
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
KEEP AS NON CORE |
Summary: Nprl2 physically interacts with Nprl3.
Reason: Interaction evidence supports protein binding, but the term is generic and not core.
Supporting Evidence:
PMID:24786828
Nprl2 and Nprl3 physically interact
|
|
GO:0005634
nucleus
|
IDA
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
UNDECIDED |
Summary: Nuclear localization is not supported by the accessible sources used for this review.
Reason: Available curated localization statements emphasize cytoplasm/lysosome/autolysosome without nuclear evidence.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
SUBCELLULAR LOCATION: Cytoplasm. Lysosome
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0005737
cytoplasm
|
IDA
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
KEEP AS NON CORE |
Summary: Nprl2 localizes to the cytoplasm.
Reason: UniProt reports cytoplasmic localization.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
SUBCELLULAR LOCATION: Cytoplasm
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0034198
cellular response to amino acid starvation
|
IMP
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
ACCEPT |
Summary: Nprl2 participates in the response to amino-acid starvation.
Reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid starvation.
Supporting Evidence:
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0044754
autolysosome
|
IDA
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
KEEP AS NON CORE |
Summary: Nprl2 localizes to autolysosomes during amino-acid starvation.
Reason: UniProt notes primary localization to autolysosomes under amino-acid starvation.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
Localizes primarily to the autolysosomes during amino-acid starvation
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0045792
negative regulation of cell size
|
IMP
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
KEEP AS NON CORE |
Summary: Nprl2 restrains TORC1-dependent cell growth, consistent with negative regulation of cell size.
Reason: GATOR1 inhibition of TORC1-dependent growth supports reduced cell size/growth phenotypes.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
inhibiting TORC1-dependent cell growth
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0048477
oogenesis
|
IMP
PMID:24786828 The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive res... |
KEEP AS NON CORE |
Summary: Nprl2 participates in oogenesis through GATOR1 control of meiotic entry and oocyte development.
Reason: UniProt describes GATOR1 roles in meiotic entry and oocyte growth.
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
control meiotic entry and promote oocyte growth and development
PMID:24786828
The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to amino-acid starvation in Drosophila.
|
|
GO:0035859
Seh1-associated complex
|
ISS
PMID:21454883 A conserved coatomer-related complex containing Sec13 and Se... |
MODIFY |
Summary: The SEA/GATOR complex term is broader than the specific GATOR1 complex membership.
Reason: Evidence supports GATOR1 subcomplex membership; use the specific GATOR1 complex term.
Proposed replacements:
GATOR1 complex
Supporting Evidence:
file:genes/DROME/Nprl2/Nprl2-uniprot.txt
Component of the GATOR complex consisting of mio, Nup44A/Seh1, Im11, Nplr3, Nplr2, Wdr24, Wdr59 and Sec13
PMID:21454883
A conserved coatomer-related complex containing Sec13 and Seh1 dynamically associates with the vacuole in Saccharomyces cerevisiae.
|
|
GO:0005096
GTPase activator activity
|
TAS
PMID:23723238 A Tumor suppressor complex with GAP activity for the Rag GTP... |
NEW |
Summary: GATOR1 provides RagA/B GAP activity that inhibits TORC1 signaling.
Reason: GATOR1 is the Nprl2/Nprl3/Iml1 complex and is reported to have GTPase-activating protein activity for RagA/B, supporting a GTPase activator activity annotation for its subunits.
Supporting Evidence:
PMID:23723238
GATOR1 has GTPase-activating protein (GAP) activity for RagA and RagB, and its components are mutated in human cancer
|
provider: falcon
model: Edison Scientific Literature
cached: true
start_time: '2026-02-01T16:13:09.428081'
end_time: '2026-02-01T16:13:09.430001'
duration_seconds: 0.0
template_file: templates/gene_research_go_focused.md
template_variables:
organism: DROME
gene_id: Nprl2
gene_symbol: Nprl2
uniprot_accession: Q9VXA0
protein_description: 'RecName: Full=GATOR complex protein NPRL2 {ECO:0000305}; AltName:
Full=Nitrogen permease regulator 2-like protein {ECO:0000312|FlyBase:FBgn0030800};'
gene_info: Name=Nprl2 {ECO:0000312|FlyBase:FBgn0030800}; ORFNames=CG9104 {ECO:0000312|FlyBase:FBgn0030800};
organism_full: Drosophila melanogaster (Fruit fly).
protein_family: Belongs to the NPR2 family. .
protein_domains: NPR2-like. (IPR009348); NPR2 (PF06218)
provider_config:
timeout: 600
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parameters:
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citation_count: 14
BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.
DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'Nprl2' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information
Please provide a comprehensive research report on the gene Nprl2 (gene ID: Nprl2, UniProt: Q9VXA0) in DROME.
The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.
You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.
We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.
We are interested in where in or outside the cell the gene product carries out its function.
We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.
Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.
Question: You are an expert researcher providing comprehensive, well-cited information.
Provide detailed information focusing on:
1. Key concepts and definitions with current understanding
2. Recent developments and latest research (prioritize 2023-2024 sources)
3. Current applications and real-world implementations
4. Expert opinions and analysis from authoritative sources
5. Relevant statistics and data from recent studies
Format as a comprehensive research report with proper citations. Include URLs and publication dates where available.
Always prioritize recent, authoritative sources and provide specific citations for all major claims.
BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.
DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'Nprl2' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information
Please provide a comprehensive research report on the gene Nprl2 (gene ID: Nprl2, UniProt: Q9VXA0) in DROME.
The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.
You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.
We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.
We are interested in where in or outside the cell the gene product carries out its function.
We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.
Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.
Plan overview
- Verified identity: Nprl2 (CG9104; FBgn0030800) in Drosophila melanogaster encodes a conserved GATOR1 subunit (UniProt Q9VXA0), belonging to the NPR2/NPRL2-like family. No symbol ambiguity was detected within D. melanogaster. (context verification)
- Evidence focus: primary Drosophila experiments on GATOR1/Nprl2 in oogenesis and DNA damage response; conserved mechanistic reviews of Rag–mTORC1 signaling; 2023 advances linking NPRL2 post‑translational regulation to methionine/SAM sensing; mammalian NPRL2 studies for localization and mTORC1‑independent roles.
Gene/protein identity verification
- Target matches UniProt Q9VXA0: Drosophila melanogaster Nprl2 (CG9104) annotated as GATOR complex protein NPRL2/Nitrogen permease regulator 2‑like; family/domain annotations concordant with NPR2/NPRL2‑like. No conflicting gene symbol usage in fly was found. (context verification)
1) Key concepts and definitions (current understanding)
- Complex membership and pathway role: Nprl2 is one of three core subunits of GATOR1 (with Iml1/DEPDC5 and Nprl3). GATOR1 is the Rag GTPase-activating protein (GAP) complex that inhibits TORC1/mTORC1 in response to amino‑acid limitation; within GATOR1, NPRL2 contains a catalytic arginine (“arginine finger”) that stimulates RagA/B GTP hydrolysis to turn off mTORC1 signaling. In metazoans, GATOR1 opposes GATOR2, which relays amino‑acid sensors to relieve GATOR1 and promote TORC1 activation when nutrients are sufficient. (lamasherpa2023 review, doi:10.1042/bst20210038, Mar 2023; URL: https://doi.org/10.1042/bst20210038) (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9)
- Drosophila functional context: In fly oogenesis, GATOR1 (Iml1/Nprl2/Nprl3) downregulates TORC1 when meiotic double-strand breaks (DSBs) arise; restraining TORC1 via GATOR1 and TSC promotes timely DSB repair and prevents excessive p53 activation. GATOR2 (Mio) antagonizes this inhibition to enable growth later in oogenesis. (Wei et al., eLife, Oct 2019; doi:10.7554/eLife.42149; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 1-3, wei2019thegatorcomplex pages 3-4)
2) Recent developments and latest research (prioritize 2023–2024)
- Post‑translational regulation of NPRL2 links methionine/SAM to GATOR1: PRMT1 cooperates with the SAM sensor SAMTOR to control mTORC1 methionine sensing by arginine methylation of NPRL2. PRMT1 selectively methylates NPRL2 (not DEPDC5/NPRL3), with asymmetric dimethylation at R6 and R78; R78 is a major functional site. SAMTOR and PRMT1 bind GATOR1 in a mutually exclusive, SAM‑responsive manner. Methionine increases lysosomal PRMT1 and mTOR localization and elevates lysosomal ADMA signals; PRMT1 activity is required for methionine/SAM‑induced mTORC1 activation and lysosomal mTORC1 colocalization. Mechanistically, methylation of NPRL2 suppresses GATOR1 GAP activity, facilitating mTORC1 activation. (Jiang et al., Cell Metabolism, Dec 2023; doi:10.1016/j.cmet.2023.11.001; URL: https://doi.org/10.1016/j.cmet.2023.11.001) (jiang2023prmt1orchestrateswith pages 1-3, jiang2023prmt1orchestrateswith pages 5-6, jiang2023prmt1orchestrateswith pages 6-8, jiang2023prmt1orchestrateswith pages 26-30)
- Consolidated 2023 perspective on Rag–lysosome control of mTORC1: Reviews reaffirm GATOR1 as RagA/B GAP, Ragulator as Rag GEF/lysosomal scaffold, and the lysosome as the mTORC1 control hub integrating amino‑acid sensors (CASTORs, Sestrins, SAMTOR) and transporters (e.g., SLC38A9). These updates refine isoform/tissue‑specific nuances and stress‑dependent lysosomal targeting of TSC2. (Biochemical Society Transactions review, Mar 2023; doi:10.1042/bst20210038; URL: https://doi.org/10.1042/bst20210038) (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9)
3) Molecular function, localization, and pathway placement
- Molecular function: Nprl2 is a GATOR1 catalytic subunit contributing the arginine finger essential for GAP activity toward RagA/B, thereby inhibiting TORC1 during amino‑acid starvation or damage responses. In Drosophila, loss of any GATOR1 subunit elevates TORC1 activity and blunts starvation‑induced autophagy. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 1-3, wei2019thegatorcomplex pages 7-9)
- Subcellular localization relevant to function: The GATOR1–Rag–Ragulator axis operates at lysosomes; Ragulator tethers Rags to lysosomes and enables mTORC1 recruitment for activation in nutrient‑replete states, whereas GATOR1’s GAP activity on Rags disengages mTORC1 when nutrients are limiting. KICSTOR recruits GATOR1 to lysosomes under stress, coordinating with Ragulator/Rags. (Lama‑Sherpa et al., 2023; URL: https://doi.org/10.1042/bst20210038) (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9); (Jiang et al., 2023; URL: https://doi.org/10.1016/j.cmet.2023.11.001) (jiang2023prmt1orchestrateswith pages 19-20)
- Potential nuclear roles and mTORC1‑independent activities (conserved insights): In human cells, NPRL2 can accumulate in the nucleus upon proteasome inhibition and its overexpression induces NOX2‑dependent ROS, DNA damage signaling, and cell‑cycle arrest, indicating functions beyond canonical mTORC1 regulation. These data suggest possible conserved non‑lysosomal roles that merit evaluation in Drosophila. (Ma et al., Sci Rep, Nov 2017; doi:10.1038/s41598-017-15497-0; URL: https://doi.org/10.1038/s41598-017-15497-0) (ma2017tumorsuppressornprl2 pages 2-4, ma2017tumorsuppressornprl2 pages 13-13)
- Placement relative to GATOR2/Mio: In the fly germline, GATOR2 (via Mio) antagonizes GATOR1/TSC to prevent prolonged TORC1 suppression after DSB‑triggered checkpoint activation, thereby permitting oocyte growth. Loss of Mio causes constitutive TORC1 downregulation and growth defects that are suppressed by reducing GATOR1 activity or preventing meiotic DSBs. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 3-4, wei2019thegatorcomplex pages 1-3)
4) Drosophila experimental phenotypes and precise roles
- Meiotic DSB response and p53 activation: GATOR1 mutants (including nprl2 and nprl3 nulls) show elevated TORC1 and delayed repair of meiotic DSBs. In GATOR1 mutants, TORC1 activity in ovaries is ~3× wild type, DSBs persist into later stages, and p53 is hyperactivated. Quantitatively, whereas <5% of region 3 cysts exhibit p53‑GFPnls signal in wild type, nearly 80% do so in GATOR1 mutants, indicating checkpoint stress. Genetic reduction of S6K dosage suppresses excess DSBs in iml1-depleted germlines, implicating TORC1→S6K in the repair delay. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 15-17, wei2019thegatorcomplex pages 7-9)
- Autophagy and starvation response: GATOR1 mutants fail to induce autophagy appropriately upon starvation, consistent with GATOR1’s role as a TORC1 inhibitor in amino‑acid limitation. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 7-9)
- Retrotransposon control: In nprl3 mutants, retrotransposon transcripts are elevated by qRT‑PCR; increases are largely suppressed when meiotic DSB formation is blocked (mei‑P22) and are additive with loss of p53, indicating that GATOR1 and p53 act in parallel to restrain transposons during DSB episodes. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 13-15)
- DNA damage sensitivity: GATOR1 mutants show reduced survival after low‑dose γ‑irradiation, consistent with compromised DNA damage responses when TORC1 is hyperactive. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 15-17)
5) Current applications and real‑world implementations
- Nutrient‑sensing therapeutics and metabolic modulation: The PRMT1–SAMTOR–GATOR1 axis offers a druggable interface connecting methionine/SAM levels to mTORC1 via NPRL2 methylation. PRMT1 inhibition or SAM lowering blunts methionine‑induced mTORC1 activation and lysosomal recruitment, suggesting strategies to modulate mTORC1 through NPRL2 PTMs. While demonstrated in mammalian systems, the conservation of GATOR1 architecture argues for translational relevance and testable hypotheses in Drosophila. (Jiang et al., 2023; URL: https://doi.org/10.1016/j.cmet.2023.11.001) (jiang2023prmt1orchestrateswith pages 26-30, jiang2023prmt1orchestrateswith pages 5-6)
- Disease relevance of GATOR1 components: Human literature continues to link DEPDC5/NPRL2/NPRL3 variants to neurological phenotypes, including epilepsy, emphasizing GATOR1’s clinical significance as a lysosomal mTORC1 checkpoint. (Review overview, Int J Mol Sci, Feb 2023; doi:10.3390/ijms24044223; URL: https://doi.org/10.3390/ijms24044223) (jiang2023prmt1orchestrateswith pages 20-21)
6) Expert opinions and authoritative perspectives
- Consensus models: Recent reviews and perspectives converge on a lysosome‑centric model where Ragulator (lysosomal scaffold/GEF) and GATOR1 (Rag GAP) integrate amino‑acid sensors to govern mTORC1 translocation and activation; TSC/Rheb integrates growth factor and stress cues at the same compartment. These models frame Nprl2 as a catalytic inhibitory node whose regulation (including arginine methylation) tunes nutrient decisions. (Biochemical Society Transactions, Mar 2023; URL: https://doi.org/10.1042/bst20210038) (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9)
- Fly germline checkpoint logic: Expert work in eLife (2019) positions GATOR1 as a key mediator of a meiotic DSB‑triggered metabolic checkpoint, with GATOR2/Mio relieving inhibition to allow growth—an elegant in vivo illustration of how nutrient and genome integrity signals intersect via TORC1 control. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 3-4, wei2019thegatorcomplex pages 1-3)
7) Relevant statistics and quantitative data from recent studies
- Drosophila oogenesis (GATOR1 mutants): TORC1 activity ~3× higher than wild type in mutant ovaries; p53 activation in region 3 cysts rises from <5% (WT) to ~80% (GATOR1 mutants); S6K dose reduction suppresses elevated DSB numbers in iml1‑depleted germlines; atg1 or 4E‑BP loss does not recapitulate the DSB phenotype, arguing for a TORC1→S6K‑specific mechanism. (Wei et al., 2019; URL: https://doi.org/10.7554/eLife.42149) (wei2019thegatorcomplex pages 15-17, wei2019thegatorcomplex pages 7-9)
- NPRL2 methylation kinetics and SAM sensitivity (mammalian cells): NPRL2 R78 asymmetric dimethylation responds to SAM availability (Km for PRMT1 on NPRL2 ~5 μM SAM); SAMTOR binds SAM with Kd ~7 μM, PRMT1 with Kd ~26 μM; methionine promotes PRMT1 and mTOR lysosomal localization and increases lysosomal ADMA signal; PRMT1 loss reduces mTOR–LAMP2 colocalization (Pearson correlation quantitation) and impairs methionine‑induced mTORC1 activation. (Jiang et al., 2023; URL: https://doi.org/10.1016/j.cmet.2023.11.001) (jiang2023prmt1orchestrateswith pages 5-6, jiang2023prmt1orchestrateswith pages 6-8, jiang2023prmt1orchestrateswith pages 26-30)
Functional annotation summary for Drosophila Nprl2 (Q9VXA0)
- Primary molecular role: Catalytic subunit of the GATOR1 complex, acting as a RagA/B GAP to inhibit TORC1 during amino‑acid starvation and in response to meiotic DSBs. (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9, wei2019thegatorcomplex pages 3-4)
- Cellular localization where function is executed: Functions at the lysosomal signaling hub through the Ragulator–Rag–GATOR1 axis; Drosophila phenotypes support pathway activity in the germline during oogenesis. (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9, wei2019thegatorcomplex pages 1-3)
- Pathway wiring: Upstream amino‑acid sensors signal via GATOR2 to modulate GATOR1; KICSTOR recruits GATOR1 to lysosomes; downstream TORC1 effectors (e.g., S6K) mediate impacts on DSB repair timing and checkpoint signaling. (jiang2023prmt1orchestrateswith pages 19-20, wei2019thegatorcomplex pages 15-17, wei2019thegatorcomplex pages 3-4)
- Phenotypic consequences of loss: Elevated TORC1, impaired starvation‑induced autophagy, delayed meiotic DSB repair, strong p53 hyperactivation, increased retrotransposon expression, and reduced survival to γ‑irradiation. (wei2019thegatorcomplex pages 7-9, wei2019thegatorcomplex pages 15-17, wei2019thegatorcomplex pages 13-15)
- Regulatory innovation (2023): Methionine/SAM‑dependent PRMT1‑mediated methylation of NPRL2 R78 attenuates GATOR1 GAP activity, providing a tunable nutrient‑sensing PTM rheostat for mTORC1 control that likely generalizes across metazoans. (jiang2023prmt1orchestrateswith pages 1-3, jiang2023prmt1orchestrateswith pages 6-8)
Notes on ambiguity
- The symbol “Nprl2/NPRL2” is used across species. All Drosophila-specific functional claims above are supported by fly studies (Wei et al., 2019). Mammalian studies (Ma 2017; Jiang 2023) are invoked to clarify conserved mechanisms (lysosomal Rag regulation; NPRL2 post‑translational control and nuclear roles) and are clearly identified as non‑fly when relevant. (wei2019thegatorcomplex pages 1-3, ma2017tumorsuppressornprl2 pages 2-4, jiang2023prmt1orchestrateswith pages 1-3)
Selected sources with URLs and dates
- Wei et al., 2019, eLife, Oct 2019. The GATOR complex regulates an essential response to meiotic double-stranded breaks in Drosophila. https://doi.org/10.7554/eLife.42149 (wei2019thegatorcomplex pages 1-3, wei2019thegatorcomplex pages 7-9, wei2019thegatorcomplex pages 15-17, wei2019thegatorcomplex pages 13-15, wei2019thegatorcomplex pages 3-4)
- Lama‑Sherpa et al., 2023, Biochemical Society Transactions, Mar 2023. Regulation of mTORC1 by the Rag GTPases. https://doi.org/10.1042/bst20210038 (lamasherpa2023regulationofmtorc1 pages 2-4, lamasherpa2023regulationofmtorc1 pages 8-9)
- Jiang et al., 2023, Cell Metabolism, Dec 2023. PRMT1 orchestrates with SAMTOR to govern mTORC1 methionine sensing via Arg‑methylation of NPRL2. https://doi.org/10.1016/j.cmet.2023.11.001 (jiang2023prmt1orchestrateswith pages 1-3, jiang2023prmt1orchestrateswith pages 5-6, jiang2023prmt1orchestrateswith pages 6-8, jiang2023prmt1orchestrateswith pages 26-30, jiang2023prmt1orchestrateswith pages 19-20)
- Ma et al., 2017, Scientific Reports, Nov 2017. Tumor suppressor NPRL2 induces ROS production and DNA damage response. https://doi.org/10.1038/s41598-017-15497-0 (ma2017tumorsuppressornprl2 pages 2-4, ma2017tumorsuppressornprl2 pages 13-13)
- Sun and Wang, 2023, Int J Mol Sci, Feb 2023. Clocking Epilepsies: A Chronomodulated Strategy‑Based Therapy for Rhythmic Seizures. https://doi.org/10.3390/ijms24044223 (jiang2023prmt1orchestrateswith pages 20-21)
Conclusion
Drosophila Nprl2 is the conserved catalytic subunit of GATOR1 that suppresses TORC1 by acting as a Rag GAP at lysosomes. In vivo, Nprl2/GATOR1 enforces a meiotic DSB‑responsive metabolic checkpoint in the germline, ensuring timely DNA repair and restraining p53 and transposon activation; GATOR2/Mio relieves this inhibition to resume growth. Recent work reveals that NPRL2 is subject to methionine/SAM‑sensitive arginine methylation by PRMT1, establishing a tunable post‑translational control over GATOR1 activity that connects one‑carbon metabolism to mTORC1. Together, these findings refine Nprl2’s placement as a central inhibitory node in nutrient and genome‑integrity signaling, with emerging therapeutic implications through modulation of NPRL2 methylation and GATOR1–lysosome interactions. (wei2019thegatorcomplex pages 3-4, wei2019thegatorcomplex pages 7-9, lamasherpa2023regulationofmtorc1 pages 2-4, jiang2023prmt1orchestrateswith pages 6-8)
References
(lamasherpa2023regulationofmtorc1 pages 2-4): Tshering D. Lama-Sherpa, Mi-Hyeon Jeong, and Jenna L. Jewell. Regulation of mtorc1 by the rag gtpases. Biochemical Society Transactions, 51:655-664, Mar 2023. URL: https://doi.org/10.1042/bst20210038, doi:10.1042/bst20210038. This article has 48 citations and is from a peer-reviewed journal.
(lamasherpa2023regulationofmtorc1 pages 8-9): Tshering D. Lama-Sherpa, Mi-Hyeon Jeong, and Jenna L. Jewell. Regulation of mtorc1 by the rag gtpases. Biochemical Society Transactions, 51:655-664, Mar 2023. URL: https://doi.org/10.1042/bst20210038, doi:10.1042/bst20210038. This article has 48 citations and is from a peer-reviewed journal.
(wei2019thegatorcomplex pages 1-3): Youheng Wei, Lucia Bettedi, Chun-Yuan Ting, Kuikwon Kim, Yingbiao Zhang, Jiadong Cai, and Mary A Lilly. The gator complex regulates an essential response to meiotic double-stranded breaks in drosophila. eLife, Oct 2019. URL: https://doi.org/10.7554/elife.42149, doi:10.7554/elife.42149. This article has 27 citations and is from a domain leading peer-reviewed journal.
(wei2019thegatorcomplex pages 3-4): Youheng Wei, Lucia Bettedi, Chun-Yuan Ting, Kuikwon Kim, Yingbiao Zhang, Jiadong Cai, and Mary A Lilly. The gator complex regulates an essential response to meiotic double-stranded breaks in drosophila. eLife, Oct 2019. URL: https://doi.org/10.7554/elife.42149, doi:10.7554/elife.42149. This article has 27 citations and is from a domain leading peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 1-3): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 5-6): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 6-8): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 26-30): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
(wei2019thegatorcomplex pages 7-9): Youheng Wei, Lucia Bettedi, Chun-Yuan Ting, Kuikwon Kim, Yingbiao Zhang, Jiadong Cai, and Mary A Lilly. The gator complex regulates an essential response to meiotic double-stranded breaks in drosophila. eLife, Oct 2019. URL: https://doi.org/10.7554/elife.42149, doi:10.7554/elife.42149. This article has 27 citations and is from a domain leading peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 19-20): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
(ma2017tumorsuppressornprl2 pages 2-4): Yinxing Ma, Licia Silveri, John LaCava, and Svetlana Dokudovskaya. Tumor suppressor nprl2 induces ros production and dna damage response. Scientific Reports, Nov 2017. URL: https://doi.org/10.1038/s41598-017-15497-0, doi:10.1038/s41598-017-15497-0. This article has 29 citations and is from a peer-reviewed journal.
(ma2017tumorsuppressornprl2 pages 13-13): Yinxing Ma, Licia Silveri, John LaCava, and Svetlana Dokudovskaya. Tumor suppressor nprl2 induces ros production and dna damage response. Scientific Reports, Nov 2017. URL: https://doi.org/10.1038/s41598-017-15497-0, doi:10.1038/s41598-017-15497-0. This article has 29 citations and is from a peer-reviewed journal.
(wei2019thegatorcomplex pages 15-17): Youheng Wei, Lucia Bettedi, Chun-Yuan Ting, Kuikwon Kim, Yingbiao Zhang, Jiadong Cai, and Mary A Lilly. The gator complex regulates an essential response to meiotic double-stranded breaks in drosophila. eLife, Oct 2019. URL: https://doi.org/10.7554/elife.42149, doi:10.7554/elife.42149. This article has 27 citations and is from a domain leading peer-reviewed journal.
(wei2019thegatorcomplex pages 13-15): Youheng Wei, Lucia Bettedi, Chun-Yuan Ting, Kuikwon Kim, Yingbiao Zhang, Jiadong Cai, and Mary A Lilly. The gator complex regulates an essential response to meiotic double-stranded breaks in drosophila. eLife, Oct 2019. URL: https://doi.org/10.7554/elife.42149, doi:10.7554/elife.42149. This article has 27 citations and is from a domain leading peer-reviewed journal.
(jiang2023prmt1orchestrateswith pages 20-21): Cong Jiang, Jing Liu, Shaohui He, Wei Xu, Runzhi Huang, Weijuan Pan, Xiaolong Li, Xiaoming Dai, Jianping Guo, Tao Zhang, Hiroyuki Inuzuka, Ping Wang, John M. Asara, Jianru Xiao, and Wenyi Wei. Prmt1 orchestrates with samtor to govern mtorc1 methionine sensing via arg-methylation of nprl2. Cell Metabolism, 35:2183-2199.e7, Dec 2023. URL: https://doi.org/10.1016/j.cmet.2023.11.001, doi:10.1016/j.cmet.2023.11.001. This article has 30 citations and is from a highest quality peer-reviewed journal.
id: Q9VXA0
gene_symbol: Nprl2
product_type: PROTEIN
status: INITIALIZED
taxon:
id: NCBITaxon:7227
label: Drosophila melanogaster
description: 'GATOR1 complex subunit that inhibits TORC1 signaling during amino acid
limitation and nutrient stress.'
existing_annotations:
- term:
id: GO:0034198
label: cellular response to amino acid starvation
evidence_type: IBA
original_reference_id: GO_REF:0000033
review: &id002
summary: Nprl2 participates in the response to amino-acid starvation.
action: ACCEPT
reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid
starvation.
supported_by:
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0005096
label: GTPase activator activity
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: GATOR1 has Rag GTPase GAP activity; Nprl2 is a GATOR1 subunit.
action: KEEP_AS_NON_CORE
reason: GTPase-activating activity is established for GATOR1 (RagA/B), so
the IBA is reasonable for Nprl2 but not the primary focus.
supported_by:
- reference_id: PMID:23723238
supporting_text: GATOR1 has GTPase-activating protein (GAP) activity for
RagA and RagB
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IBA
original_reference_id: GO_REF:0000033
review: &id001
summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid
starvation.
action: ACCEPT
reason: Both UniProt and the starvation study describe Nprl2-mediated
inhibition of TORC1 in response to amino-acid limitation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: functions as an inhibitor of the amino acid-sensing
branch of the TORC1 signaling pathway
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 inhibit TORC1 signaling in the female
germline in response to amino-acid starvation.
- term:
id: GO:0005774
label: vacuolar membrane
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: The vacuolar membrane term is yeast-specific; Drosophila data
indicate lysosomal localization.
action: MODIFY
reason: Replace vacuolar membrane with lysosome to match the Drosophila
localization evidence.
proposed_replacement_terms:
- id: GO:0005764
label: lysosome
supported_by:
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 physically interact and are targeted to
lysosomes and autolysosomes
- term:
id: GO:1990130
label: GATOR1 complex
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: Nprl2 is a core subunit of the GATOR1 complex.
action: ACCEPT
reason: UniProt annotates Nprl2 as a probable GATOR1 subcomplex component,
supporting this complex membership.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: probable component of the GATOR1 subcomplex which is
likely composed of Iml1, Nplr2 and Nplr3
- reference_id: file:genes/DROME/Nprl2/Nprl2-deep-research-falcon.md
supporting_text: Nprl2 is one of three core subunits of GATOR1 (with
Iml1/DEPDC5 and Nprl3).
- term:
id: GO:0005737
label: cytoplasm
evidence_type: IEA
original_reference_id: GO_REF:0000044
review:
summary: Nprl2 localizes to the cytoplasm.
action: KEEP_AS_NON_CORE
reason: UniProt reports cytoplasmic localization.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: 'SUBCELLULAR LOCATION: Cytoplasm'
- term:
id: GO:0005764
label: lysosome
evidence_type: IEA
original_reference_id: GO_REF:0000044
review:
summary: Nprl2 localizes to lysosomes under nutrient stress.
action: KEEP_AS_NON_CORE
reason: Lysosomal targeting is reported for Nprl2/Nprl3.
supported_by:
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 physically interact and are targeted to
lysosomes and autolysosomes
- term:
id: GO:0051301
label: cell division
evidence_type: IEA
original_reference_id: GO_REF:0000043
review:
summary: General cell division is too broad relative to the specific
mitotic-to-meiotic transition role.
action: MARK_AS_OVER_ANNOTATED
reason: Evidence indicates a specific mitotic/meiotic transition control
rather than broad cell division.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: down-regulate TORC1 to slow cellular metabolism and
promote the mitotic/meiotic transition
- term:
id: GO:0051321
label: meiotic cell cycle
evidence_type: IEA
original_reference_id: GO_REF:0000043
review:
summary: Meiotic cell cycle is captured more precisely by germline
mitotic-to-meiotic switching.
action: MODIFY
reason: Use the more specific germline cell cycle switching term supported
by ovarian cyst data.
proposed_replacement_terms:
- id: GO:0051729
label: germline cell cycle switching, mitotic to meiotic cell cycle
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: down-regulate TORC1 to slow cellular metabolism and
promote the mitotic/meiotic transition
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IEA
original_reference_id: GO_REF:0000117
review: *id001
- term:
id: GO:0034198
label: cellular response to amino acid starvation
evidence_type: NAS
original_reference_id: PMID:24786828
review: *id002
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: NAS
original_reference_id: PMID:24786828
review: *id001
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IMP
original_reference_id: PMID:24786828
review: *id001
- term:
id: GO:0009267
label: cellular response to starvation
evidence_type: IMP
original_reference_id: PMID:27672113
review:
summary: Starvation response is supported but primarily in the amino-acid
limitation context.
action: KEEP_AS_NON_CORE
reason: Evidence supports amino-acid starvation response; the broader
starvation term is acceptable but not core.
supported_by:
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- reference_id: PMID:27672113
supporting_text: The GATOR1 Complex Regulates Metabolic Homeostasis and
the Response to Nutrient Stress in Drosophila melanogaster.
- term:
id: GO:0010898
label: positive regulation of triglyceride catabolic process
evidence_type: IMP
original_reference_id: PMID:27672113
review:
summary: Nprl2 affects TAG storage, but direct positive regulation of
triglyceride catabolism is not shown.
action: MARK_AS_OVER_ANNOTATED
reason: Reported phenotype is reduced TAG storage in mutants, which does not
directly demonstrate increased triglyceride catabolism.
supported_by:
- reference_id: PMID:27672113
supporting_text: nprl2 and nprl3 mutant adults contain reduced amounts of
stored TAG relative to wild-type animals
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IGI
original_reference_id: PMID:27672113
review:
summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid
starvation.
action: ACCEPT
reason: Both UniProt and the starvation study describe Nprl2-mediated
inhibition of TORC1 in response to amino-acid limitation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: functions as an inhibitor of the amino acid-sensing
branch of the TORC1 signaling pathway
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 inhibit TORC1 signaling in the female
germline in response to amino-acid starvation.
- reference_id: PMID:27672113
supporting_text: The GATOR1 Complex Regulates Metabolic Homeostasis and
the Response to Nutrient Stress in Drosophila melanogaster.
- term:
id: GO:0051729
label: germline cell cycle switching, mitotic to meiotic cell cycle
evidence_type: IGI
original_reference_id: PMID:25512509
review:
summary: Nprl2 promotes the mitotic-to-meiotic transition in germline cysts
via TORC1 inhibition.
action: KEEP_AS_NON_CORE
reason: GATOR1 members down-regulate TORC1 to promote the mitotic/meiotic
transition.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: down-regulate TORC1 to slow cellular metabolism and
promote the mitotic/meiotic transition
- reference_id: PMID:25512509
supporting_text: TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic
entry and oocyte development in Drosophila.
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IMP
original_reference_id: PMID:27672113
review:
summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid
starvation.
action: ACCEPT
reason: Both UniProt and the starvation study describe Nprl2-mediated
inhibition of TORC1 in response to amino-acid limitation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: functions as an inhibitor of the amino acid-sensing
branch of the TORC1 signaling pathway
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 inhibit TORC1 signaling in the female
germline in response to amino-acid starvation.
- reference_id: PMID:27672113
supporting_text: The GATOR1 Complex Regulates Metabolic Homeostasis and
the Response to Nutrient Stress in Drosophila melanogaster.
- term:
id: GO:0035859
label: Seh1-associated complex
evidence_type: IDA
original_reference_id: PMID:27166823
review:
summary: The SEA/GATOR complex term is broader than the specific GATOR1
complex membership.
action: MODIFY
reason: Evidence supports GATOR1 subcomplex membership; use the specific
GATOR1 complex term.
proposed_replacement_terms:
- id: GO:1990130
label: GATOR1 complex
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: Component of the GATOR complex consisting of mio,
Nup44A/Seh1, Im11, Nplr3, Nplr2, Wdr24, Wdr59 and Sec13
- reference_id: PMID:27166823
supporting_text: The GATOR2 Component Wdr24 Regulates TORC1 Activity and
Lysosome Function.
- term:
id: GO:1904262
label: negative regulation of TORC1 signaling
evidence_type: IGI
original_reference_id: PMID:27166823
review:
summary: Nprl2 inhibits TORC1 signaling, especially under amino-acid
starvation.
action: ACCEPT
reason: Both UniProt and the starvation study describe Nprl2-mediated
inhibition of TORC1 in response to amino-acid limitation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: functions as an inhibitor of the amino acid-sensing
branch of the TORC1 signaling pathway
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 inhibit TORC1 signaling in the female
germline in response to amino-acid starvation.
- reference_id: PMID:27166823
supporting_text: The GATOR2 Component Wdr24 Regulates TORC1 Activity and
Lysosome Function.
- term:
id: GO:1990130
label: GATOR1 complex
evidence_type: TAS
original_reference_id: PMID:27166823
review:
summary: Nprl2 is a core subunit of the GATOR1 complex.
action: ACCEPT
reason: UniProt annotates Nprl2 as a probable GATOR1 subcomplex component,
supporting this complex membership.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: probable component of the GATOR1 subcomplex which is
likely composed of Iml1, Nplr2 and Nplr3
- reference_id: PMID:27166823
supporting_text: The GATOR2 Component Wdr24 Regulates TORC1 Activity and
Lysosome Function.
- term:
id: GO:0032007
label: negative regulation of TOR signaling
evidence_type: IMP
original_reference_id: PMID:23723238
review:
summary: This term is too general for the specific TORC1 inhibition shown
for Nprl2.
action: MODIFY
reason: Evidence supports inhibition of TORC1 specifically; replace with the
TORC1-specific term.
proposed_replacement_terms:
- id: GO:1904262
label: negative regulation of TORC1 signaling
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: functions as an inhibitor of the amino acid-sensing
branch of the TORC1 signaling pathway
- reference_id: PMID:23723238
supporting_text: A Tumor suppressor complex with GAP activity for the Rag
GTPases that signal amino acid sufficiency to mTORC1.
- term:
id: GO:0034198
label: cellular response to amino acid starvation
evidence_type: IMP
original_reference_id: PMID:23723238
review:
summary: Nprl2 participates in the response to amino-acid starvation.
action: ACCEPT
reason: The Nprl2/Nprl3 complex mediates an adaptive response to amino-acid
starvation.
supported_by:
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- reference_id: PMID:23723238
supporting_text: A Tumor suppressor complex with GAP activity for the Rag
GTPases that signal amino acid sufficiency to mTORC1.
- term:
id: GO:0007293
label: germarium-derived egg chamber formation
evidence_type: IGI
original_reference_id: PMID:25512509
review:
summary: Evidence points to oogenesis/meiotic entry roles rather than the
specific egg chamber formation term.
action: MODIFY
reason: Use the broader oogenesis term supported by meiotic entry/oocyte
development data.
proposed_replacement_terms:
- id: GO:0048477
label: oogenesis
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: control meiotic entry and promote oocyte growth and
development
- reference_id: PMID:25512509
supporting_text: TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic
entry and oocyte development in Drosophila.
- term:
id: GO:0005515
label: protein binding
evidence_type: IPI
original_reference_id: PMID:24786828
review:
summary: Nprl2 physically interacts with Nprl3.
action: KEEP_AS_NON_CORE
reason: Interaction evidence supports protein binding, but the term is
generic and not core.
supported_by:
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 physically interact
- term:
id: GO:0005634
label: nucleus
evidence_type: IDA
original_reference_id: PMID:24786828
review:
summary: Nuclear localization is not supported by the accessible sources
used for this review.
action: UNDECIDED
reason: Available curated localization statements emphasize
cytoplasm/lysosome/autolysosome without nuclear evidence.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: 'SUBCELLULAR LOCATION: Cytoplasm. Lysosome'
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0005737
label: cytoplasm
evidence_type: IDA
original_reference_id: PMID:24786828
review:
summary: Nprl2 localizes to the cytoplasm.
action: KEEP_AS_NON_CORE
reason: UniProt reports cytoplasmic localization.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: 'SUBCELLULAR LOCATION: Cytoplasm'
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0034198
label: cellular response to amino acid starvation
evidence_type: IMP
original_reference_id: PMID:24786828
review: *id002
- term:
id: GO:0044754
label: autolysosome
evidence_type: IDA
original_reference_id: PMID:24786828
review:
summary: Nprl2 localizes to autolysosomes during amino-acid starvation.
action: KEEP_AS_NON_CORE
reason: UniProt notes primary localization to autolysosomes under amino-acid
starvation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: Localizes primarily to the autolysosomes during
amino-acid starvation
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0045792
label: negative regulation of cell size
evidence_type: IMP
original_reference_id: PMID:24786828
review:
summary: Nprl2 restrains TORC1-dependent cell growth, consistent with
negative regulation of cell size.
action: KEEP_AS_NON_CORE
reason: GATOR1 inhibition of TORC1-dependent growth supports reduced cell
size/growth phenotypes.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: inhibiting TORC1-dependent cell growth
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0048477
label: oogenesis
evidence_type: IMP
original_reference_id: PMID:24786828
review:
summary: Nprl2 participates in oogenesis through GATOR1 control of meiotic
entry and oocyte development.
action: KEEP_AS_NON_CORE
reason: UniProt describes GATOR1 roles in meiotic entry and oocyte growth.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: control meiotic entry and promote oocyte growth and
development
- reference_id: PMID:24786828
supporting_text: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive
response to amino-acid starvation in Drosophila.
- term:
id: GO:0035859
label: Seh1-associated complex
evidence_type: ISS
original_reference_id: PMID:21454883
review:
summary: The SEA/GATOR complex term is broader than the specific GATOR1
complex membership.
action: MODIFY
reason: Evidence supports GATOR1 subcomplex membership; use the specific
GATOR1 complex term.
proposed_replacement_terms:
- id: GO:1990130
label: GATOR1 complex
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-uniprot.txt
supporting_text: Component of the GATOR complex consisting of mio,
Nup44A/Seh1, Im11, Nplr3, Nplr2, Wdr24, Wdr59 and Sec13
- reference_id: PMID:21454883
supporting_text: A conserved coatomer-related complex containing Sec13 and
Seh1 dynamically associates with the vacuole in Saccharomyces
cerevisiae.
- term:
id: GO:0005096
label: GTPase activator activity
evidence_type: TAS
original_reference_id: PMID:23723238
review:
summary: GATOR1 provides RagA/B GAP activity that inhibits TORC1 signaling.
action: NEW
reason: GATOR1 is the Nprl2/Nprl3/Iml1 complex and is reported to have
GTPase-activating protein activity for RagA/B, supporting a GTPase
activator activity annotation for its subunits.
supported_by:
- reference_id: PMID:23723238
supporting_text: GATOR1 has GTPase-activating protein (GAP) activity for
RagA and RagB, and its components are mutated in human cancer
references:
- id: GO_REF:0000033
title: Annotation inferences using phylogenetic trees
findings: []
- id: GO_REF:0000043
title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
findings: []
- id: GO_REF:0000044
title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular
Location vocabulary mapping, accompanied by conservative changes to GO terms
applied by UniProt
findings: []
- id: GO_REF:0000117
title: Electronic Gene Ontology annotations created by ARBA machine learning
models
findings: []
- id: PMID:21454883
title: A conserved coatomer-related complex containing Sec13 and Seh1
dynamically associates with the vacuole in Saccharomyces cerevisiae.
findings: []
- id: PMID:23723238
title: A Tumor suppressor complex with GAP activity for the Rag GTPases that
signal amino acid sufficiency to mTORC1.
findings: []
- id: PMID:24786828
title: The TORC1 inhibitors Nprl2 and Nprl3 mediate an adaptive response to
amino-acid starvation in Drosophila.
findings: []
- id: PMID:25512509
title: TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entry and
oocyte development in Drosophila.
findings: []
- id: PMID:27166823
title: The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lysosome
Function.
findings: []
- id: PMID:27672113
title: The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to
Nutrient Stress in Drosophila melanogaster.
findings: []
core_functions:
- description: Nprl2 is a GATOR1 subunit that contributes to Rag
GTPase-activating activity to inhibit TORC1 during amino acid starvation.
supported_by:
- reference_id: file:genes/DROME/Nprl2/Nprl2-deep-research-falcon.md
supporting_text: Nprl2 is one of three core subunits of GATOR1 (with
Iml1/DEPDC5 and Nprl3).
- reference_id: PMID:24786828
supporting_text: Nprl2 and Nprl3 inhibit TORC1 signaling in the female
germline in response to amino-acid starvation.
molecular_function:
id: GO:0005096
label: GTPase activator activity
directly_involved_in:
- id: GO:1904262
label: negative regulation of TORC1 signaling
- id: GO:0034198
label: cellular response to amino acid starvation
in_complex:
id: GO:1990130
label: GATOR1 complex