vps1302 (O42926, SPBC16C6.02c) notes

2026-10-21 — Full re-review, independent of the ProtNLM2 predictions

Context: reviewed in its own right as the sequence relative of SCHPO/spo2. ProtNLM2
output was not consulted.

just deep-research-falcon SCHPO vps1302 --fallback perplexity-lite failed: falcon
(Edison) returned 403 on authentication and the perplexity-lite fallback returned
401 (insufficient quota). No deep-research file exists; the review is based on the
cached literature listed below and PomBase/UniProt/PANTHER data.

3131 aa VPS13-family protein; UniProt PE=2 (transcript level); Chorein N-terminal
domain (2-115) and SHR-BD domain (2085-2363) predicted (ECO:0000255).
PANTHER: PTHR16166:SF93 (VPS13), same subfamily as S. cerevisiae VPS13 (Q07878).
The other S. pombe family member in the repo PANTHER table, vps1301 (P87319), is in
a different subfamily (SF145). PomBase lists S. cerevisiae YLL040C (VPS13) as the
ortholog, and human VPS13A/VPS13C. So transfer from S. cerevisiae Vps13 is
phylogenetically grounded at the subfamily level, and PAINT nodes PTN000414878 and
PTN000414879 cover it.
Spo2 (C6Y4C2) is 100% identical to Vps1302 residues 2999-3131
(file:SCHPO/vps1302/vps1302-bioinformatics/RESULTS.md). A meiotic transcript from
the 3' end of the locus encodes Spo2; vps1302 deletions remove the Spo2 ORF too.

No GO annotation with experimental evidence. All GO terms are IBA/ISS/IEA/TAS.
Deletion viable (PMID:20473289, PMID:23697806).
FK506 screen PMID:21850271; moderate micafungin
sensitivity; normal vacuole fusion PMID:21850271. The paper's
"vacuole protein sorting" category for Vps1302 comes from GeneDB annotation, not an
assay PMID:21850271. ORFeome GFP
localization: "no apparent signal".
Meiotic chromosome segregation phenotype (PMID:29259000) and tunicamycin
sensitivity (PMID:28945192) per PomBase; not used for GO (downstream phenotypes;
meiotic phenotypes confounded by the nested spo2 ORF).

Lipid binding and transfer: Kumar 2018 (PMID:30093493) yeast Vps13 N-terminal
fragment binds ~10 glycerophospholipids per molecule and transfers them in vitro;
Li 2020 (PMID:32182622) cryo-EM groove.
Contact sites: endosome/vacuole-mitochondria and NVJ (PMID:27280386,
PMID:26370498), Mcp1 adaptor (PMID:28864540), competitive adaptors (PMID:30018089).
TGN-to-PVC transport and PA/PIP binding (PMID:28122955); Golgi localization via
Arf1 (PMID:34830155); ER-phagy (PMID:32690699); prospore membrane (PMID:22442115).

Core: phospholipid transfer activity (IBA+ISS), intermembrane phospholipid transfer
(TAS; IBA/ISS lipid transfer rows refined to it), endosome membrane and
mitochondrial outer membrane (IBA).
Non-core: phospholipid binding, Golgi apparatus (IEA from by-similarity text),
mitochondrion organization, macroautophagy.
No NEW terms: no S. pombe experimental data supports any additional term, and
S. cerevisiae terms that PAINT did not propagate (prospore membrane, Golgi to
endosome transport, NVJ, reticulophagy) were treated as deliberate.