gut2 (SPCC1223.03c; UniProt O14400) encodes the mitochondrial FAD-dependent glycerol-3-phosphate dehydrogenase (EC 1.1.5.3). It oxidises sn-glycerol 3-phosphate to dihydroxyacetone phosphate and passes the electrons to the quinone pool of the respiratory chain. With the cytosolic NAD-dependent glycerol-3-phosphate dehydrogenases (gpd1, gpd2), it can form a glycerol-3-phosphate shuttle that moves cytosolic NADH reducing equivalents into respiration. It is mitochondrial in a genome-wide screen; function is assigned by orthology to S. cerevisiae GUT2.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0004368 glycerol-3-phosphate dehydrogenase (quinone) activity | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT inference from characterised FAD-dependent G3P dehydrogenases (S. cerevisiae GUT2, mammalian GPD2); gut2 is the single S. pombe member. Sound. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone file:SCHPO/gut2/gut2-uniprot.txt EC=1.1.5.3; |
| GO:0004368 glycerol-3-phosphate dehydrogenase (quinone) activity | IEA GO_REF:0000120 | ACCEPT | Summary: EC 1.1.5.3 / RHEA:18977 InterPro mapping; consistent with the IBA. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone |
| GO:0005739 mitochondrion | HDA PMID:16823372 ORFeome cloning and global analysis of protein localization ... | ACCEPT | Summary: ORFeome YFP screen placed gut2 in mitochondria. Supporting Evidence: PMID:16823372 we determined the localization of 4,431 proteins |
| GO:0005739 mitochondrion | IBA GO_REF:0000033 | ACCEPT | Summary: Phylogenetic inference; agrees with the HDA. Supporting Evidence: PMID:16823372 we determined the localization of 4,431 proteins file:SCHPO/gut2/gut2-uniprot.txt SUBCELLULAR LOCATION: Mitochondrion {ECO:0000250}. |
| GO:0005739 mitochondrion | IEA GO_REF:0000044 | ACCEPT | Summary: UniProt subcellular-location mapping. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt SUBCELLULAR LOCATION: Mitochondrion {ECO:0000250}. |
| GO:0005741 mitochondrial outer membrane | ISO GO_REF:0000024 | MARK AS OVER ANNOTATED | Summary: Transfer from S. cerevisiae Gut2, whose outer-membrane annotation comes from organelle proteomics. FAD-dependent G3P dehydrogenases are generally described as facing the intermembrane space on the inner membrane, where they reduce ubiquinone. No S. pombe data distinguish outer from inner membrane. mitochondrion and mitochondrial membrane capture what is known. Reason: Sub-mitochondrial placement transferred by similarity is not well supported. Propagation Review Root cause: SOURCE WEAK OR INFERRED Failure modes: COMPARTMENT OR COMPLEX MISMATCH SOURCE EVIDENCE WEAK Sources checked: SGD:S000001417 · S. cerevisiae GUT2 SOURCE WEAK OR INFERRED Donor outer-membrane annotation rests on organelle proteomics; the sub-mitochondrial membrane of FAD-G3PDH is not resolved by that data, so transfer of the specific membrane is not justified. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt SUBCELLULAR LOCATION: Mitochondrion {ECO:0000250}. |
| GO:0006072 glycerol-3-phosphate metabolic process | IBA GO_REF:0000033 | ACCEPT | Summary: The enzyme oxidises sn-glycerol 3-phosphate; correct general process. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone |
| GO:0006072 glycerol-3-phosphate metabolic process | IEA GO_REF:0000002 | ACCEPT | Summary: InterPro mapping; as above. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone |
| GO:0006127 glycerol-3-phosphate shuttle | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: PAINT inference of a role in the glycerol-3-phosphate shuttle (cytosolic NAD-G3PDH gpd1/gpd2 plus mitochondrial FAD-G3PDH). Plausible, as S. pombe has both components, but not tested. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone |
| GO:0019563 glycerol catabolic process | IEA GO_REF:0000041 | MARK AS OVER ANNOTATED | Summary: UniPathway "glycerol degradation via glycerol kinase pathway" mapping. In S. pombe, glycerol assimilation requires gld1, the glycerol dehydrogenase of the dihydroxyacetone route; a glycerol kinase route through gut2 has not been shown. Reason: UniPathway pathway transferred from S. cerevisiae is not established for fission yeast. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt PATHWAY: Polyol metabolism; glycerol degradation via glycerol kinase PMID:20396879 glycerol dehydrogenase encoded by gld1 (+) is essential for glycerol |
| GO:0031966 mitochondrial membrane | IEA GO_REF:0000117 | ACCEPT | Summary: ARBA mapping to mitochondrial membrane; consistent with FAD-G3PDH being a membrane-associated quinone reductase. Supporting Evidence: file:SCHPO/gut2/gut2-uniprot.txt Reaction=a quinone + sn-glycerol 3-phosphate = dihydroxyacetone file:SCHPO/gut2/gut2-uniprot.txt SUBCELLULAR LOCATION: Mitochondrion {ECO:0000250}. |
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