pgl-1

UniProt ID: Q9TZQ3
Organism: Caenorhabditis elegans
Review Status: COMPLETE
πŸ“ Provide Detailed Feedback

Gene Description

PGL-1 is an RNA-binding P-granule scaffold in Caenorhabditis elegans germ cells. Self-association and recruitment of RNA and protein partners help organize germ granules; PGL-1 directly binds the translation initiation factor IFE-1 and supports its granule localization. PGL-1 also promotes FBF-2 recruitment and RNA repression, and its assembly supports WAGO-1-dependent repression of tethered reporter mRNA. Its central dimerization domain also has guanosine-specific single-stranded RNA endonuclease activity in vitro, although the native substrates and physiological role of that catalysis remain unresolved. PGL-1 supports germline proliferation, gametogenesis and fertility, with temperature-sensitive defects and partial redundancy with PGL-3. It also suppresses excessive apoptosis and regulates CED-4 protein levels and SIR-2.1 localization. PGL-1 is a constituent of cytoplasmic germ granules, including perinuclear granules in the adult germline.

Existing Annotations Review

GO Term Evidence Action Reason
GO:0003724 RNA helicase activity
IBA
GO_REF:0000033
UNDECIDED
Summary: Inherited RNA helicase activity remains unresolved against the target-specific PGL structural evidence.
Reason: The exact Q9TZQ3/PTN002773363 leaf really descends from helicase IBD PTN002774595, without a known helicase-loss node on its path. Two experimentally characterized PGL dimerization domains and the absence of conventional DEAD-box patterns create a specific conflict with its DDX39-like placement. The focused OpenScientist report supports that architecture difference, but overstates it as a direct helicase refutation: its strict control patterns need correction, the structures cover domains rather than full-length protein, and the 2016 experiments assay RNase cleavage, not ATP-driven unwinding. Live GO:0003724 requires ATP-driven unwinding. The reported GAR1 classification is only a 629–728 RGG-tail match, not a verified full-protein reassignment or misgraft. Retain UNDECIDED after completed report review; curator inspection of the actual MSA/sequence placement and a direct unwinding assay remain discriminating follow-ups.
Propagation Review
Root cause: UNRESOLVED
Sources checked:
PANTHER:PTN002774595 UNRESOLVED
Exact positive descent remains verified. PGL domain structures and the reproduced motif differences raise a concrete alignment/identity question for its DDX39-like placement. Neither the partial GAR1-tail match nor the report establishes a misgraft or a direct negative helicase assay.
Supporting Evidence:
file:worm/pgl-1/pgl-1-paint-lineage.md
This is a real positive ancestry, not an off-clade target or a missing-source failure.
PMID:26787882
PGL-1 DD has a novel 13 Ξ±-helix fold that creates a positively charged channel as a homodimer.
file:worm/pgl-1/pgl-1-bioinformatics/RESULTS.md
PGL-1 lacks all five tested patterns, including versions allowing the actual GLH-1 residues.
file:worm/pgl-1/pgl-1-report-assessment.md
No direct helicase-negative assay is reported in these Results or Methods.
file:worm/pgl-1/pgl-1-hypotheses/pgl-fold-and-inherited-helicase-rna-processing/openscientist.md
This would convert the sequence/structure-based helicase refutation into a direct negative result.
GO:0003729 mRNA binding
IBA
GO_REF:0000033
ACCEPT
Summary: PGL-1 retains mRNA binding as an inherited RNA-recognition function.
Reason: The exact target descends from mRNA-binding IBD PTN002776867. PGL RNA-binding and RNA recruitment to granules are independently established. This term does not require preference for mRNA over every other RNA class; absence of that selectivity is not a reason to replace it with generic RNA binding. The unresolved helicase architecture does not contradict mRNA binding itself.
Supporting Evidence:
file:worm/pgl-1/pgl-1-paint-lineage.md
The target descends from PTN002776867 (mRNA binding), PTN002774595 (RNA helicase),
PMID:21402787
PGL proteins autonomously form RNP granules that contain endogenous RNA, PABP, and certain coexpressed C. elegans P-granule components.
GO:0000398 mRNA splicing, via spliceosome
IBA
GO_REF:0000033
UNDECIDED
Summary: Inherited mRNA splicing, via spliceosome remains unresolved against the target-specific PGL structural evidence.
Reason: The exact target descends from positive spliceosomal-process IBD PTN002776405. Its experimentally characterized PGL scaffold architecture conflicts with the conventional DDX39-like family placement and warrants an MSA/sequence audit, but no spliceosomal contribution has been directly refuted. The focused report acknowledges untested noncatalytic participation, then recommends rejection from absence of target experiments and cytoplasmic localization; those are insufficient grounds to negate an inherited process. The later primary study establishes scaffold-dependent reporter repression, with WAGO-1 required for full repression, rather than testing splicing. That positive post-transcriptional role neither proves nor excludes a spliceosomal role. Retain UNDECIDED for the concrete placement/function conflict after report incorporation, not because an IBA lacks target-specific experimental duplication.
Propagation Review
Root cause: UNRESOLVED
Sources checked:
PANTHER:PTN002776405 UNRESOLVED
Positive descent is established. The target-domain/DDX39-placement discrepancy is unresolved, but loss of helicase catalysis would not exclude a noncatalytic spliceosomal role. The report supplies no direct negative splicing assay.
Supporting Evidence:
file:worm/pgl-1/pgl-1-paint-lineage.md
This is a real positive ancestry, not an off-clade target or a missing-source failure.
PMID:26787882
PGL-1 DD has a novel 13 Ξ±-helix fold that creates a positively charged channel as a homodimer.
file:worm/pgl-1/pgl-1-hypotheses/pgl-fold-and-inherited-helicase-rna-processing/openscientist.md
Noncatalytic moonlighting is untested, not disproven.
file:worm/pgl-1/pgl-1-report-assessment.md
The unresolved issue is the alignment and sequence identity supporting this actual placement, not donor number.
PMID:33579952
These results also provide direct evidence that granule formation alone is not sufficient for mRNA regulation
GO:0006406 mRNA export from nucleus
IBA
GO_REF:0000033
UNDECIDED
Summary: Inherited mRNA export from nucleus remains unresolved against the target-specific PGL structural evidence.
Reason: The exact target inherits mRNA export from positive IBD PTN002776405. PGL-specific structural architecture still requires reconciliation with this DDX39-like placement. The focused report does not resolve that alignment/identity issue, and its claim that export work must occur on the inner nuclear face is too restrictive: GO:0006406 covers directed movement to the cytoplasm. P granules receive newly exported transcripts, and full PMID:22991439 discusses their continuity with the pore environment while demonstrating PGL-1-dependent FBF-2 localization and efficient mRNA binding. Those are compatible contextual observations, not a direct PGL-1 export assay; cytoplasmic/perinuclear localization cannot refute export participation. Retain UNDECIDED for the specific unresolved placement and process contribution, assessed independently from helicase activity and without a duplicate provider request.
Propagation Review
Root cause: UNRESOLVED
Sources checked:
PANTHER:PTN002776405 UNRESOLVED
The target lies below this positive export node. A PGL structural/sequence-placement discrepancy remains, but the partial GAR1 match does not identify a misgraft. Export at the cytoplasmic pore interface remains possible; neither missing target assays nor loss of catalytic helicase activity is a process-level refutation.
Supporting Evidence:
file:worm/pgl-1/pgl-1-paint-lineage.md
This is a real positive ancestry, not an off-clade target or a missing-source failure.
PMID:26787882
PGL-1 DD has a novel 13 Ξ±-helix fold that creates a positively charged channel as a homodimer.
PMID:22991439
P granules are major sites of RNA export from the nucleus
PMID:20223759
newly exported mRNAs are collected prior to their release to the general cytoplasm
file:worm/pgl-1/pgl-1-hypotheses/pgl-fold-and-inherited-helicase-rna-processing/openscientist.md
Noncatalytic moonlighting is untested, not disproven.
file:worm/pgl-1/pgl-1-report-assessment.md
These observations do not prove that PGL-1 executes export, but cytoplasmic localization does not refute it.
GO:0003723 RNA binding
IEA
GO_REF:0000043
ACCEPT
Summary: RNA binding is a core function of PGL-1 mediated by its RGG repeats. The protein binds RNA to recruit it into P granules and also has ribonuclease activity that requires RNA binding. This annotation is well-supported despite being IEA.
Reason: PGL-1 contains RGG repeats that are well-characterized RNA-binding motifs. The protein recruits RNA into P granules and has demonstrated ribonuclease activity, both requiring RNA binding capability. This is a fundamental molecular function of the protein.
Supporting Evidence:
PMID:21402787
an RGG box for recruiting RNA and RNA-binding proteins
GO:0004518 nuclease activity
IEA
GO_REF:0000043
ACCEPT
Summary: The broad nuclease annotation is consistent with directly demonstrated RNA endonuclease activity.
Reason: PMID:26787882 establishes guanosine-specific single-stranded RNA endonucleolysis. Nuclease and endonuclease are true broader activities; a more specific retained term does not make the electronic annotation biologically incorrect.
Supporting Evidence:
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
GO:0004519 endonuclease activity
IEA
GO_REF:0000043
ACCEPT
Summary: The broad nuclease annotation is consistent with directly demonstrated RNA endonuclease activity.
Reason: PMID:26787882 establishes guanosine-specific single-stranded RNA endonucleolysis. Nuclease and endonuclease are true broader activities; a more specific retained term does not make the electronic annotation biologically incorrect.
Supporting Evidence:
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
GO:0016787 hydrolase activity
IEA
GO_REF:0000043
ACCEPT
Summary: The assigned overall guanyl-RNase reaction supports broad hydrolase activity.
Reason: UniProt explicitly assigns a reaction consuming H2O and producing a 3β€²-phosphate RNA fragment. The cyclizing reaction is classified as a lyase by EC and GO, but that classification does not exclude a hydrolytic step in the overall reaction. GO:0046589 is not an ontological child of hydrolase; the broad annotation is instead supported by the curated reaction itself. Primary evidence establishes G-specific cleavage while the exact novel PGL catalytic mechanism remains open. Neither broadness nor lack of a separate product-mechanism assay justifies rejecting the curated chemical assignment.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
Reaction=[RNA] containing guanosine + H2O
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
GO:0016829 lyase activity
IEA
GO_REF:0000043
ACCEPT
Summary: This annotation is correct. PGL-1 has lyase activity because it generates 2,3-cyclic phosphate intermediates when cleaving RNA, which is characteristic of lyase-type ribonucleases like RNase T1.
Reason: Retain the curated EC/keyword mapping at its inferred chemical-reaction scope. Direct biochemical evidence establishes guanosine-specific RNA endonucleolysis, while UniProt assigns the cyclizing RNase reaction. Exact product chemistry and native substrate use are less directly established than the cleavage itself; this annotation does not imply that RNase catalysis is required for granule assembly or fertility.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
formation of a corresponding 2',3'-cyclic phosphate intermediate
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
GO:0030154 cell differentiation
IEA
GO_REF:0000043
ACCEPT
Summary: PGL-1 contributes to germline cell differentiation and development.
Reason: The broad electronic cell-differentiation term is consistent with the experimental germline phenotypes and granule organization role. More specific existing germline terms add detail without refuting this ancestor.
Supporting Evidence:
PMID:9741628
its primary function is in germline proliferation.
GO:0046589 ribonuclease T1 activity
IEA
GO_REF:0000003
ACCEPT
Summary: This annotation is essentially correct. PGL-1 has guanosine-specific ribonuclease activity similar to RNase T1, cleaving RNA after guanosine residues and generating 2,3-cyclic phosphates. The EC number 4.6.1.24 confirms this. The direct biochemical/structural evidence comes from Aoki et al. 2016 (PMID:26787882, IDA), which demonstrated guanosine-specific ssRNA cleavage and identified catalytic residues by mutagenesis. Note that the falcon deep research (focused on 2023-2024 germ-granule literature) could not independently retrieve the underlying enzymology and therefore treated the RNase function as "unverified in this report"; this reflects the corpus accessible to falcon rather than a genuine contradiction, since the primary biochemical paper provides direct catalytic evidence. Recent compartment-mapping literature continues to label PGL-1 a P-granule endoribonuclease.
Reason: Retain the curated EC/keyword mapping at its inferred chemical-reaction scope. Direct biochemical evidence establishes guanosine-specific RNA endonucleolysis, while UniProt assigns the cyclizing RNase reaction. Exact product chemistry and native substrate use are less directly established than the cleavage itself; this annotation does not imply that RNase catalysis is required for granule assembly or fertility.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
formation of a corresponding 2',3'-cyclic phosphate intermediate
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
GO:0048477 oogenesis
IEA
GO_REF:0000043
ACCEPT
Summary: This annotation is correct. PGL-1 is essential for oogenesis in C. elegans. Loss of PGL-1 leads to defective oocyte production and female sterility, especially at elevated temperatures.
Reason: PGL-1 is required for correct oogenesis. Mutants show defective oocyte production and hermaphrodites lacking PGL-1 have impaired fertility due to oogenesis defects. This is experimentally validated by multiple studies.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
required for correct oogenesis
PMID:9741628
Elimination of PGL-1 results in defective germ granules and sterility.
GO:0005515 protein binding
IPI
PMID:11641215
An isoform of eIF4E is a component of germ granules and is r...
REMOVE
Summary: PGL-1 directly interacts with IFE-1 and recruits it to P granules.
Reason: Remove the generic protein-binding annotation because it does not describe a specific molecular function. The interaction evidence and source attribution are retained; this curation action does not assert that the reported association is false. The inspected evidence does not justify an informative replacement function for this particular row.
Supporting Evidence:
PMID:11641215
In vitro PGL-1 interacts directly with IFE-1, but not with the other four isoforms of eIF4E.
GO:0005515 protein binding
IPI
PMID:14704431
A map of the interactome network of the metazoan C. elegans.
UNDECIDED
Summary: The experimentally curated interaction from the worm Y2H interactome is retained.
Reason: The curated interaction is not contradicted, but the accessible evidence does not expose the target-specific assay needed to choose a more informative molecular function. Leave this row unresolved pending source inspection; generic protein binding is not accepted as a functional synthesis, and lack of accessible assay detail is not evidence that the interaction is false.
Supporting Evidence:
PMID:14704431
more than 4000 interactions were identified from high-throughput, yeast two-hybrid (HT=Y2H) screens.
GO:0004521 RNA endonuclease activity
IDA
PMID:26787882
PGL germ granule assembly protein is a base-specific, single...
ACCEPT
Summary: PGL-1 has directly demonstrated guanosine-specific ssRNA endonuclease activity.
Reason: The primary study establishes cleavage by the PGL dimerization domain. Native RNA substrates and the physiological contribution of this activity remain unresolved; RNase-defective mutants can retain the tested in vivo functions. The molecular activity is supported independently of those downstream process questions.
Supporting Evidence:
PMID:26787882
PGL-1 DD is a guanosine-specific, single-stranded endonuclease
PMID:26787882
that enzymatic activity is dispensable in vivo.
GO:0042802 identical protein binding
IPI
PMID:26787882
PGL germ granule assembly protein is a base-specific, single...
ACCEPT
Summary: Excellent annotation. PGL-1 homodimerization is structurally and functionally characterized. The dimerization domain is essential for P granule assembly and the protein forms homodimers as building blocks.
Reason: Crystal structure and biochemical studies confirm PGL-1 forms homodimers through its dimerization domain. This self-association is fundamental to P granule assembly and represents a core molecular function.
Supporting Evidence:
PMID:26787882
PGL-1 DD has a novel 13 Ξ±-helix fold that creates a positively charged channel as a homodimer.
file:worm/pgl-1/pgl-1-uniprot.txt
Homodimer
GO:0005515 protein binding
IPI
PMID:31283754
The demethylase NMAD-1 regulates DNA replication and repair ...
UNDECIDED
Summary: The NMAD-1-associated protein-interaction evidence is retained.
Reason: The curated interaction is not contradicted, but the accessible evidence does not expose the target-specific assay needed to choose a more informative molecular function. Leave this row unresolved pending source inspection; generic protein binding is not accepted as a functional synthesis, and lack of accessible assay detail is not evidence that the interaction is false.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
Interacts with nmad-1
PMID:31283754
we used immunoprecipitation and mass spectrometry to identify NMAD-1 binding proteins.
GO:0043186 P granule
IDA
PMID:28182654
ELLI-1, a novel germline protein, modulates RNAi activity an...
ACCEPT
Summary: Excellent cellular component annotation. PGL-1 is a core structural component of P granules, experimentally validated by direct observation.
Reason: PGL-1 is a defining component of P granules. It localizes to these germline-specific cytoplasmic granules throughout development and is essential for their assembly. This is fundamental to its cellular localization.
Supporting Evidence:
PMID:28182654
ELLI-1, a novel germline protein, modulates RNAi activity and P-granule accumulation in Caenorhabditis elegans.
file:worm/pgl-1/pgl-1-uniprot.txt
Localizes to P granules in germline precursor cells
GO:0043186 P granule
IDA
PMID:19361491
The C. elegans sex determination gene laf-1 encodes a putati...
ACCEPT
Summary: PGL-1 is the P-granule colocalization marker in the LAF-1 study.
Reason: The primary abstract explicitly reports LAF-1 colocalization with PGL-1 in germline precursor granules. This supports PGL-1 location, not transfer of LAF-1 helicase activity.
Supporting Evidence:
PMID:19361491
LAF-1 is predominantly, if not exclusively, cytoplasmic and colocalizes with PGL-1 in P granules of germline precursor cells.
GO:0043186 P granule
IDA
PMID:26015579
The disordered P granule protein LAF-1 drives phase separati...
ACCEPT
Summary: The PGL-1 granule localization observation is retained from the LAF-1 phase-separation study.
Reason: WormBase curates an IDA location observation from this study. The paper primarily characterizes LAF-1, so its phase-separation mechanism must not be reassigned to PGL-1 merely because PGL-1 marks the granules. Independent PGL-1 localization and scaffold studies corroborate the location.
Supporting Evidence:
PMID:9741628
PGL-1 is a predicted RNA-binding protein that is present on germ granules at all stages of development.
GO:0003723 RNA binding
ISS
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: Early prediction of RNA binding based on RGG repeats, later confirmed experimentally. This annotation is correct and represents a core molecular function.
Reason: The initial sequence-based prediction of RNA binding through RGG repeats has been validated by subsequent experimental work showing PGL-1 binds and cleaves RNA. This is a fundamental molecular function.
Supporting Evidence:
PMID:21402787
an RGG box for recruiting RNA and RNA-binding proteins
GO:0007276 gamete generation
IMP
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: Excellent annotation. PGL-1 mutants are sterile due to defects in both oogenesis and spermatogenesis, demonstrating essential role in gamete generation.
Reason: Genetic evidence clearly shows PGL-1 is essential for gamete generation. Mutants fail to produce functional oocytes and sperm, resulting in sterility. This is a core biological function.
Supporting Evidence:
PMID:9741628
Elimination of PGL-1 results in defective germ granules and sterility.
file:worm/pgl-1/pgl-1-deep-research.md
mutant males have defective sperm production and mutant hermaphrodites have faulty oocyte production
PMID:15238518
The PGL family proteins associate with germ granules and function redundantly in Caenorhabditis elegans germline development.
GO:0022414 reproductive process
IMP
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: PGL-1 contributes to reproductive development through germline proliferation and gametogenesis.
Reason: The source IMP annotation is biologically consistent with the primary fertility and germline defects. Being broader than gamete generation or oogenesis does not make it non-core or erroneous.
Supporting Evidence:
PMID:9741628
Elimination of PGL-1 results in defective germ granules and sterility.
GO:0030719 P granule organization
IMP
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: Excellent annotation for a core function. PGL-1 is essential for P granule assembly and organization, acting as a scaffold protein that nucleates granule formation.
Reason: PGL-1 is a fundamental P granule scaffold protein. Loss of PGL-1 results in defective or absent P granules. The protein self-associates and recruits other components to form organized P granules. This is a defining biological function.
Supporting Evidence:
PMID:21402787
an RGG box for recruiting RNA and RNA-binding proteins
PMID:9741628
Elimination of PGL-1 results in defective germ granules and sterility.
GO:0042078 germ-line stem cell division
IMP
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: PGL-1 is required for germline proliferation. Mutants show germline proliferation defects with insufficient mitotic germ cells, supporting this annotation.
Reason: PGL-1 mutants exhibit early germ cell proliferation arrest, failing to maintain the population of mitotically dividing germ cells. This demonstrates a requirement for germline stem cell division.
Supporting Evidence:
PMID:9741628
its primary function is in germline proliferation.
file:worm/pgl-1/pgl-1-uniprot.txt
population of proliferating germ cells
GO:0043186 P granule
IDA
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: Original demonstration of PGL-1 localization to P granules. This foundational observation established PGL-1 as a P granule component.
Reason: This is the original paper identifying PGL-1 as a P granule component present at all developmental stages. This fundamental localization is essential to understanding PGL-1 function.
Supporting Evidence:
PMID:9741628
PGL-1 is a predicted RNA-binding protein that is present on germ granules at all stages of development.
file:worm/pgl-1/pgl-1-deep-research-falcon.md
PGL-1 localizes to **perinuclear P granules** in the adult germline, a positioning that connects germ granules to nuclear pores and nascent transcripts.
GO:0048477 oogenesis
IMP
PMID:9741628
PGL-1, a predicted RNA-binding component of germ granules, i...
ACCEPT
Summary: Well-supported annotation. PGL-1 is required for oogenesis, with mutants showing defective or absent oocyte production.
Reason: Genetic evidence demonstrates PGL-1 is essential for oogenesis. Mutant hermaphrodites have defective oocyte production, particularly at elevated temperatures, confirming this biological role.
Supporting Evidence:
file:worm/pgl-1/pgl-1-uniprot.txt
required for correct oogenesis
PMID:9741628
Elimination of PGL-1 results in defective germ granules and sterility.
GO:0043066 negative regulation of apoptotic process
IMP
PMID:26598553
Loss of PGL-1 and PGL-3, members of a family of constitutive...
NEW
Summary: PGL-1 negatively regulates apoptosis, with evidence for control of CED-4 protein expression.
Reason: Retain this existing authored IMP proposal based on germline loss-of-function, ectopic-expression sufficiency and PGL-1-dependent changes in CED-4 reporter protein despite unchanged ced-4 RNA in the somatic model. PGL-1 therefore supplies regulatory work rather than merely being necessary for cell viability. Exact molecular effectors remain unresolved: no direct PGL-1/SIR-2.1 sequestration complex or direct ced-4 RNA interaction is asserted. QuickGO ancestry checked on 2026-09-20 has no parent/child redundancy with the existing process rows.
Supporting Evidence:
PMID:26598553
We conclude that PGL proteins suppress excessive germline apoptosis by repressing both the protein levels of CED-4 and the cytoplasmic translocation of SIR-2.1.
PMID:27650246
CED-4::GFP expression was recovered to a higher level by RNAi depletion of pgl-1 in hpl-2-mutant embryos compared to mock RNAi-treated hpl-2-mutant embryos

Core Functions

PGL-1 self-associates through N-terminal and central dimerization domains and recruits RNA/protein components to provide the scaffold for P-granule organization, supporting germline development.

Molecular Function:
identical protein binding
Directly Involved In:
Cellular Locations:
Supporting Evidence:
  • PMID:26787882
    PGL-1 DD has a novel 13 Ξ±-helix fold that creates a positively charged channel as a homodimer.
  • PMID:21402787
    PGL proteins autonomously form RNP granules that contain endogenous RNA, PABP, and certain coexpressed C. elegans P-granule components.
  • PMID:33579952
    Mutations of those interface residues prevent P granule assembly in vivo, de-repress PGL-1 tethered mRNA, and reduce fertility.

PGL-1 binds RNA in germline RNP granules and recruits RNA-regulatory partners, including IFE-1 and FBF-2. Granule assembly supports repression of tethered reporter mRNA, with WAGO-1 required for full repression; this does not assign the repressive effector chemistry to PGL-1 RNase.

Molecular Function:
RNA binding
Directly Involved In:
Cellular Locations:
Supporting Evidence:
  • PMID:21402787
    an RGG box for recruiting RNA and RNA-binding proteins
  • PMID:11641215
    The association of IFE-1 with P granules requires the P-granule protein PGL-1.
  • PMID:22991439
    PGL-1 is required to localize FBF-2 to perinuclear P granules and for efficient binding of FBF-2 to its mRNA targets.
  • PMID:33579952
    These results also provide direct evidence that granule formation alone is not sufficient for mRNA regulation

The PGL-1 central dimerization domain cleaves single-stranded RNA with guanosine specificity in vitro. Native cleavage targets and the physiological role remain unresolved. The RNase-defective Q342A allele retained fertility in the tested temperature conditions; RNA cleavage is not established as the cause of P-granule organization, fertility or tethered-reporter repression.

Molecular Function:
RNA endonuclease activity
Cellular Locations:
Supporting Evidence:
  • PMID:26787882
    PGL-1 DD is a guanosine-specific, single-stranded endonuclease
  • file:worm/pgl-1/pgl-1-report-assessment.md
    That distinguishes RNase activity from the fertility requirement; it does not establish that RNase activity has no in vivo function in any condition.

References

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Suggested Questions for Experts

Q: Can a PAINT curator reconcile the exact Q9TZQ3 sequence/MSA beneath positive helicase PTN002774595 and splicing/export PTN002776405 with both PGL dimerization domains? The report is incorporated but did not establish a misgraft; its GAR1 match covers only the RGG tail. Which of the three inherited capacities is supported independently by direct full-length unwinding or target-resolved RNA-processing/export evidence?

Q: Which physiological RNAs are cleaved by PGL-1, what are the reaction products, and does it catalyse a water-dependent hydrolytic step as well as the assigned cyclizing reaction?

Q: How does PGL-1 lower CED-4 protein and alter SIR-2.1 localization, and is either effect mediated by direct RNA recognition or a demonstrable sequestration complex?

Suggested Experiments

Experiment: RNA-seq of PGL-1 immunoprecipitates to identify direct RNA targets and analysis of RNA cleavage sites

Hypothesis: PGL-1 binds and cleaves specific germline mRNAs involved in cell fate determination and translational control

Type: Biochemical RNA-seq analysis

Experiment: Systematic mutagenesis of PGL-1 ribonuclease active site and dimerization domains to separate enzymatic and scaffolding functions

Hypothesis: PGL-1's ribonuclease activity and scaffolding function are separable and have distinct roles in germline development

Type: Structure-function mutagenesis

Experiment: Time-lapse microscopy of P granule dynamics and PGL-1 behavior in wild-type vs mutant backgrounds at permissive vs restrictive temperatures

Hypothesis: Temperature affects PGL-1 stability, P granule assembly dynamics, or protein interactions critical for germline function

Type: Live cell imaging at different temperatures

Experiment: Single-cell analysis of SIR-2.1, CED-4, and other apoptosis factors in PGL-1 mutant germ cells to map the apoptosis regulatory network

Hypothesis: PGL-1 coordinates a specific subcellular organization that spatially regulates pro- and anti-apoptotic factors

Type: Single-cell proteomics of apoptosis regulation

Tags

caeel-p-granules

Deep Research

Falcon

(pgl-1-deep-research-falcon.md)

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Deep Research Report: pgl-1 (worm)

(pgl-1-deep-research.md)

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OpenScientist

(pgl-1-hypotheses/pgl-fold-and-inherited-helicase-rna-processing/openscientist.md)

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πŸ“š Additional Documentation

Notes

(pgl-1-notes.md)

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Bioinformatics Results

(RESULTS.md)

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Bioreason Rl Predictions

(pgl-1-bioreason-rl-predictions.md)

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Bioreason Rl Review

(pgl-1-bioreason-rl-review.md)

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Paint Lineage

(pgl-1-paint-lineage.md)

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Report Assessment

(pgl-1-report-assessment.md)

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πŸ“„ View Raw YAML

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