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this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.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.
The requested target is ral2 from Schizosaccharomyces pombe (fission yeast), corresponding to a Ras-pathway regulatory factor historically described as a “putative activator of Ras1” and as a “Ras1–Scd pathway protein,” rather than the Ral small-GTPase family known in metazoans. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6, hakuno1996theschizosaccharomycespombe pages 2-4, kawamukai2024regulationofsexual pages 3-3)
A key point for identity verification is that the gene symbol “ral2” is used in older fission-yeast Ras1 signaling genetics, where “ral” denotes Ras-activation/related loci (ral1/scd1, ral2, ral3/scd2) rather than Ras-like small GTPases. (hakuno1996theschizosaccharomycespombe pages 2-4)
In S. pombe, Ras1 functions as a signaling hub important for mating/sexual differentiation and polarized growth. Genetic analyses place ral2 among factors that positively regulate Ras1 signaling and thereby influence mating efficiency and cell morphology. (hakuno1996theschizosaccharomycespombe pages 2-4, imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6)
In the Ras GTPase cycle, Ras activity is set by opposing activities: guanine nucleotide exchange (activators) versus GTP hydrolysis promotion (GAPs). In the available primary genetic evidence, ral2 is treated as a positive regulator of Ras1 whose mechanism was unresolved: the ral2 product was hypothesized either to function as a GDP→GTP exchange-type activator for Ras1 or to act indirectly by negatively regulating the Ras1 GAP Gap1, thereby increasing Ras1-GTP. (imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6)
Kelch repeats are ~44–56 aa motifs occurring in 5–7 repeats in many proteins and commonly forming β-propeller structures, generally functioning as protein–protein interaction modules. A broad phylogenetic analysis of the Kelch-repeat superfamily explicitly lists a fission yeast protein “Ral-2” as a Kelch-repeat protein with “Kelch and unique” architecture. (prag2003molecularphylogenyof pages 11-13)
Across independent fission-yeast genetics studies, ral2 is most consistently supported as a positive regulator of Ras1 signaling (a “putative activator of Ras1”), functioning in Ras1-dependent control of mating competence and cell shape/polarized growth. (hakuno1996theschizosaccharomycespombe pages 2-4, imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6)
A major phenotype class associated with ral2 (and related ral loci) is mating deficiency, and ral mutants are described as having roundish (depolarized) morphology, consistent with impaired Ras1-dependent polarized growth regulation. (hakuno1996theschizosaccharomycespombe pages 2-4, imai1991identificationofa pages 1-2)
A strong line of evidence comes from suppressor/epistasis mapping around Ras1 regulation:
- Suppressor analyses and epistasis tests indicate that gap1 null can bypass the requirement for ral2 to maintain Ras in a GTP-bound state, consistent with ral2 acting to promote Ras1 activity in opposition to Gap1. (imai1991identificationofa pages 3-5)
- Point mutations in the ras1 ORF can suppress ral2 defects, supporting the idea that ral2 acts upstream of or on Ras1 activation rather than simply affecting ras1 expression. (imai1991identificationofa pages 5-6)
Collectively, these results support that Ral2’s primary role is control of Ras1 activation state, impacting mating signaling output and morphogenesis. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6)
Multiple sources (including a comparative fungal study summarizing S. pombe work) describe S. pombe Ral2 as containing three Kelch repeats at its N-terminus, and place it in the Ras1–Scd pathway. (qu2021poral2isinvolved pages 3-5)
Additionally, a Kelch-repeat phylogeny includes S. pombe “Ral-2” as a Kelch-repeat protein with a “Kelch and unique” architecture (and does not present it as a canonical BTB/Kelch protein). (prag2003molecularphylogenyof pages 11-13)
A Pyricularia/Magnaporthe homolog (PoRal2) is described as containing N-terminal Kelch repeats and a C-terminal BTB domain, but this does not, by itself, constitute direct experimental or sequence-annotation proof that S. pombe Ral2 contains a BTB domain. (qu2021poral2isinvolved pages 3-5)
The older Kelch-repeat phylogeny explicitly notes that yeast Kelch proteins studied at the time did not correspond to BTB/Kelch proteins, even while listing fission yeast Ral-2 among Kelch proteins. (prag2003molecularphylogenyof pages 11-13)
Therefore, within the tool-retrieved literature here, Kelch-repeat status is supported, but BTB/POZ-domain assignment for S. pombe Ral2 is not conclusively supported (and should be verified directly from UniProt/PomBase sequence/domain annotations or the original primary papers). (qu2021poral2isinvolved pages 3-5, prag2003molecularphylogenyof pages 11-13)
No direct subcellular localization evidence for S. pombe Ral2 (e.g., microscopy localization) was retrieved in the accessible texts used here; the available sources primarily provide genetic/pathway placement and domain-level inference. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6, hakuno1996theschizosaccharomycespombe pages 2-4)
Direct 2023–2024 primary research specifically on S. pombe ral2 was not retrieved in the current tool run; however, two relevant “recent” contributions provide updated context:
1) 2024 review of sexual differentiation initiation in S. pombe: ral2 is included as a “Ras1–Scd pathway protein” in a curated pathway table, reflecting continued recognition of ral2 as a Ras-pathway component in modern syntheses of mating control. Publication date: March 2024. URL: https://doi.org/10.1093/bbb/zbae019 (kawamukai2024regulationofsexual pages 3-3)
2) General 2023–2024 advances in BTB/Kelch and ubiquitin-ligase adaptor biology are extensive, but because a BTB domain for S. pombe Ral2 is not directly supported in the retrieved evidence, those advances can only be applied cautiously as hypothesis-generating context rather than as ral2-specific updates. (prag2003molecularphylogenyof pages 11-13, qu2021poral2isinvolved pages 3-5)
The clearest real-world “implementation” of ral2 biology is as part of the S. pombe toolkit for dissecting conserved Ras signaling logic (Ras activation/deactivation control; mating signaling output; polarized growth). Primary genetics demonstrates how upstream regulators (ral2; gap1) and Ras1 alleles interact to tune Ras activation state and downstream phenotypes. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 5-6)
Ral2 homologs in plant-pathogenic fungi have been studied in infection-related development (e.g., appressorium formation). A 2021 study explicitly frames a rice blast fungus homolog as “homologous to S. pombe Ral2,” leveraging the fission yeast pathway context to motivate functional studies in pathogenesis. Publication date: September 2021. URL: https://doi.org/10.3389/fpls.2021.702368 (qu2021poral2isinvolved pages 3-5)
This is not a direct application of S. pombe ral2 in industry, but it is a practical example of how functional inference from yeast signaling modules informs pathogenic-fungus gene characterization. (qu2021poral2isinvolved pages 3-5)
The following table distinguishes direct evidence (genetic/pathway) from secondary/inferred claims (e.g., specific protein–protein interactions; BTB domain assignment in S. pombe):
| Claim category | Specific claim | Evidence source (paper) | Pub year | DOI/URL | Evidence snippet (paraphrased) | Confidence |
|---|---|---|---|---|---|---|
| identity | The target in the literature is Schizosaccharomyces pombe ral2, a Ras1-pathway regulatory gene/product, not a Ras-family small GTPase. | Imai et al., Mol Cell Biol; Hakuno et al., Genes Cells; Kawamukai, Biosci Biotechnol Biochem | 1991; 1996; 2024 | https://doi.org/10.1128/mcb.11.6.3088-3094.1991 ; https://doi.org/10.1046/j.1365-2443.1996.27029.x ; https://doi.org/10.1093/bbb/zbae019 | Multiple sources describe ral2 as a “putative activator of Ras1” or “Ras1-Scd pathway protein,” distinguishing it from ras1 itself. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6, hakuno1996theschizosaccharomycespombe pages 2-4, kawamukai2024regulationofsexual pages 3-3) | High |
| domains | S. pombe Ral2 is reported to contain N-terminal kelch repeats. | Qu et al., Front Plant Sci | 2021 | https://doi.org/10.3389/fpls.2021.702368 | Comparative discussion of S. pombe Ral2 states it has three kelch repeats at the N-terminus and belongs to the Ras1-Scd pathway context. (qu2021poral2isinvolved pages 1-2, qu2021poral2isinvolved pages 3-5) | Medium |
| domains | Older kelch-family phylogeny lists S. pombe Ral-2 as a kelch-repeat protein with “Kelch and unique” architecture, not as a canonical BTB/kelch protein. | Prag & Adams, BMC Bioinformatics | 2003 | https://doi.org/10.1186/1471-2105-4-42 | Table-based annotation places S. pombe Ral-2 among kelch-repeat proteins and notes yeasts lacked BTB/kelch proteins in that analysis. (prag2003molecularphylogenyof pages 11-13) | Medium |
| domains | Direct support for a BTB/POZ domain in S. pombe Ral2 is not established by the gathered primary evidence; BTB is explicit for the Pyricularia homolog, not unequivocally for S. pombe in these texts. | Qu et al., Front Plant Sci; Prag & Adams, BMC Bioinformatics | 2021; 2003 | https://doi.org/10.3389/fpls.2021.702368 ; https://doi.org/10.1186/1471-2105-4-42 | The fungal homolog PoRal2 is described with a C-terminal BTB domain, but the gathered S. pombe-focused evidence only clearly supports kelch repeats and Ras1-pathway assignment. (qu2021poral2isinvolved pages 11-13, qu2021poral2isinvolved pages 3-5, prag2003molecularphylogenyof pages 11-13) | Medium |
| function | ral2 likely functions as a positive regulator/activator of Ras1. | Imai et al., Mol Cell Biol; Hakuno et al., Genes Cells | 1991; 1996 | https://doi.org/10.1128/mcb.11.6.3088-3094.1991 ; https://doi.org/10.1046/j.1365-2443.1996.27029.x | Genetic studies repeatedly frame ral2 as a putative Ras1 activator; the mechanism remained unresolved. (hakuno1996theschizosaccharomycespombe pages 2-4, imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6) | High |
| pathway | ral2 acts in the Ras1-Scd signaling pathway tied to mating and morphogenesis. | Qu et al., Front Plant Sci; Kawamukai, Biosci Biotechnol Biochem | 2021; 2024 | https://doi.org/10.3389/fpls.2021.702368 ; https://doi.org/10.1093/bbb/zbae019 | Recent review and comparative paper both label ral2 as a Ras1-Scd pathway protein. (qu2021poral2isinvolved pages 11-13, qu2021poral2isinvolved pages 3-5, kawamukai2024regulationofsexual pages 3-3) | High |
| pathway | Genetic evidence places ral2 upstream of or affecting Ras1 activation, with intimate linkage to the Ras-GTPase cycle and interaction logic involving Gap1. | Imai et al., Mol Cell Biol | 1991 | https://doi.org/10.1128/mcb.11.6.3088-3094.1991 | Suppressor and epistasis analyses showed gap1 null could bypass ral2 requirement for maintaining Ras1-GTP, supporting a role in Ras1 activation control. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6) | High |
| phenotype | ral2 mutants are associated with mating deficiency. | Hakuno et al., Genes Cells; Imai et al., Mol Cell Biol | 1996; 1991 | https://doi.org/10.1046/j.1365-2443.1996.27029.x ; https://doi.org/10.1128/mcb.11.6.3088-3094.1991 | ral genes, including ral2, were cloned from mutants defective in mating; loss of ral2 gives phenotypes similar to reduced Ras1 signaling. (hakuno1996theschizosaccharomycespombe pages 2-4, imai1991identificationofa pages 1-2) | High |
| phenotype | ral2 mutants show roundish/abnormal cell morphology, linking ral2 to polarized growth control. | Hakuno et al., Genes Cells | 1996 | https://doi.org/10.1046/j.1365-2443.1996.27029.x | The ral mutant class is described as mating-deficient with roundish morphology, and ral-linked signaling is tied to Ras1-dependent morphology regulation. (hakuno1996theschizosaccharomycespombe pages 2-4) | High |
| phenotype | Earlier comparative discussion also links S. pombe ral2 to control of cell morphology, conjugation/mating, and sporulation. | Qu et al., Front Plant Sci | 2021 | https://doi.org/10.3389/fpls.2021.702368 | Review-style summary of prior S. pombe literature states Ral2 participates in morphology, conjugation, and sporulation; this is secondary reporting of older work. (qu2021poral2isinvolved pages 1-2) | Medium |
| interactions | Evidence from gathered texts supports a functional/genetic relationship between Ral2 and Ras1, and between Ral2 and Gap1. | Imai et al., Mol Cell Biol | 1991 | https://doi.org/10.1128/mcb.11.6.3088-3094.1991 | ras1 activating mutations suppress ral2 defects, and gap1 epistasis indicates ral2 operates in the Ras1 regulatory cycle. (imai1991identificationofa pages 3-5, imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6) | High |
| interactions | Secondary reporting indicates S. pombe Ral2 has been reported to interact with Gef1 and Skp1, but these claims were not directly verified here from the original S. pombe primary papers. | Qu et al., Front Plant Sci | 2021 | https://doi.org/10.3389/fpls.2021.702368 | Comparative fungal paper summarizes earlier S. pombe work saying Ral2 interacts with Gef1 and Skp1; this remains indirect evidence in the present retrieval set. (qu2021poral2isinvolved pages 1-2, qu2021poral2isinvolved pages 11-13) | Low |
| notes | Mechanistically, ral2 was hypothesized to act either as a GDP-GTP exchange-type activator for Ras1 or as an indirect negative regulator of Gap1, but the exact biochemical mechanism remained unresolved. | Imai et al., Mol Cell Biol | 1991 | https://doi.org/10.1128/mcb.11.6.3088-3094.1991 | Authors explicitly discuss alternative mechanistic models for how ral2 promotes Ras1 activity. (imai1991identificationofa pages 1-2, imai1991identificationofa pages 5-6) | High |
| notes | Direct primary paper not retrieved here: Fukui et al. 1989 is repeatedly cited as the original ral2 characterization, but only secondary references to it were available in the current evidence set. | Fukui et al., Mol Cell Biol (cited as unobtainable in search results) | 1989 | https://doi.org/10.1128/mcb.9.12.5617-5622.1989 | The foundational paper on ral2 characterization was identified but not retrievable in the current tool output; conclusions attributed to it here are therefore partly mediated through later sources. (qu2021poral2isinvolved pages 1-2, hakuno1996theschizosaccharomycespombe pages 2-4) | High |
Table: This table consolidates the gathered evidence for S. pombe ral2/SPBC21.05c (UniProt P15258), separating direct support from indirect or secondary claims. It is useful for distinguishing well-supported conclusions about Ras1-pathway function and phenotype from less certain domain and interaction annotations.
The foundational primary paper “Characterization of the S. pombe ral2 gene implicated in activation of the ras1 gene product” (Fukui et al., 1989; Molecular and Cellular Biology) was identified but not retrievable within this tool session. Consequently, some frequently repeated statements (e.g., specific domain architecture details beyond Kelch repeats; direct physical interactions such as with Skp1 and Gef1) are currently supported only via secondary reporting in later literature rather than by direct quotation from the 1989 primary source. (qu2021poral2isinvolved pages 1-2, hakuno1996theschizosaccharomycespombe pages 2-4)
References
(imai1991identificationofa pages 3-5): Yoshiyuki Imai, Sanae Miyake, David A. Hughes, and Masayuki Yamamoto. Identification of a gtpase-activating protein homolog in schizosaccharomyces pombe. Molecular and Cellular Biology, 11:3088-3094, Jun 1991. URL: https://doi.org/10.1128/mcb.11.6.3088-3094.1991, doi:10.1128/mcb.11.6.3088-3094.1991. This article has 93 citations and is from a domain leading peer-reviewed journal.
(imai1991identificationofa pages 1-2): Yoshiyuki Imai, Sanae Miyake, David A. Hughes, and Masayuki Yamamoto. Identification of a gtpase-activating protein homolog in schizosaccharomyces pombe. Molecular and Cellular Biology, 11:3088-3094, Jun 1991. URL: https://doi.org/10.1128/mcb.11.6.3088-3094.1991, doi:10.1128/mcb.11.6.3088-3094.1991. This article has 93 citations and is from a domain leading peer-reviewed journal.
(imai1991identificationofa pages 5-6): Yoshiyuki Imai, Sanae Miyake, David A. Hughes, and Masayuki Yamamoto. Identification of a gtpase-activating protein homolog in schizosaccharomyces pombe. Molecular and Cellular Biology, 11:3088-3094, Jun 1991. URL: https://doi.org/10.1128/mcb.11.6.3088-3094.1991, doi:10.1128/mcb.11.6.3088-3094.1991. This article has 93 citations and is from a domain leading peer-reviewed journal.
(hakuno1996theschizosaccharomycespombe pages 2-4): Fumihiko Hakuno, David A. Hughes, and Masayuki Yamamoto. The schizosaccharomyces pombe mra1 gene, which is required for cell growth and mating, can suppress the mating inefficiency caused by a deficit in the ras1 activity. Genes to Cells, 1:303-315, Mar 1996. URL: https://doi.org/10.1046/j.1365-2443.1996.27029.x, doi:10.1046/j.1365-2443.1996.27029.x. This article has 13 citations and is from a peer-reviewed journal.
(kawamukai2024regulationofsexual pages 3-3): Makoto Kawamukai. Regulation of sexual differentiation initiation in schizosaccharomyces pombe. Bioscience, biotechnology, and biochemistry, 88:475-492, Mar 2024. URL: https://doi.org/10.1093/bbb/zbae019, doi:10.1093/bbb/zbae019. This article has 16 citations.
(prag2003molecularphylogenyof pages 11-13): Soren Prag and Josephine C Adams. Molecular phylogeny of the kelch-repeat superfamily reveals an expansion of btb/kelch proteins in animals. BMC Bioinformatics, 4:42-42, Sep 2003. URL: https://doi.org/10.1186/1471-2105-4-42, doi:10.1186/1471-2105-4-42. This article has 213 citations and is from a peer-reviewed journal.
(qu2021poral2isinvolved pages 3-5): Yingmin Qu, Jing Wang, Pengyun Huang, Xiaohong Liu, Jianping Lu, and Fu-Cheng Lin. Poral2 is involved in appressorium formation and virulence via pmk1 mapk pathways in the rice blast fungus pyricularia oryzae. Frontiers in Plant Science, Sep 2021. URL: https://doi.org/10.3389/fpls.2021.702368, doi:10.3389/fpls.2021.702368. This article has 28 citations.
(qu2021poral2isinvolved pages 1-2): Yingmin Qu, Jing Wang, Pengyun Huang, Xiaohong Liu, Jianping Lu, and Fu-Cheng Lin. Poral2 is involved in appressorium formation and virulence via pmk1 mapk pathways in the rice blast fungus pyricularia oryzae. Frontiers in Plant Science, Sep 2021. URL: https://doi.org/10.3389/fpls.2021.702368, doi:10.3389/fpls.2021.702368. This article has 28 citations.
(qu2021poral2isinvolved pages 11-13): Yingmin Qu, Jing Wang, Pengyun Huang, Xiaohong Liu, Jianping Lu, and Fu-Cheng Lin. Poral2 is involved in appressorium formation and virulence via pmk1 mapk pathways in the rice blast fungus pyricularia oryzae. Frontiers in Plant Science, Sep 2021. URL: https://doi.org/10.3389/fpls.2021.702368, doi:10.3389/fpls.2021.702368. This article has 28 citations.