Sol3 (YHR163W) is a 6-phosphogluconolactonase (EC 3.1.1.31) of Saccharomyces cerevisiae. It hydrolyses 6-phospho-D-glucono-1,5-lactone to 6-phospho-D-gluconate, the second step of the oxidative pentose phosphate pathway, between glucose-6-phosphate dehydrogenase (Zwf1) and 6-phosphogluconate dehydrogenase (Gnd1/Gnd2). It belongs to the four-member Sol family (NagB/RpiA-like fold). Only Sol3 and its closest paralog Sol4 have detectable lactonase activity and act redundantly; Sol1 and Sol2 lack activity and instead affect tRNA nuclear export. Sol3 is predominantly cytosolic, with some nuclear GFP signal in genome-wide screens.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0005634 nucleus | HDA PMID:14562095 Global analysis of protein localization in budding yeast. | KEEP AS NON CORE | Summary: Huh et al. GFP-tagging scored Sol3-GFP in the nucleus and the cytoplasm. Stanford et al. note that Sol3 and Sol4 have no detectable role in tRNA nuclear export (unlike the paralogs Sol1/Sol2) and are predominantly cytosolic. No nuclear function is known for Sol3. Reason: High-throughput nuclear signal without a nuclear role; the enzyme acts in the cytosol. Supporting Evidence: PMID:14562095 We classify these proteins, representing 75% of the yeast proteome, into 22 distinct subcellular localization categories PMID:15454531 A recent genome-wide project reported Sol1-GFP, Sol3-GFP, and Sol4-GFP to be located in the nucleus and the cytosol PMID:15454531 Sol3p and Sol4p, which have little or no detectable effect upon los1 suppression or tRNA biogenesis, are located predominantly in the cytosol |
| GO:0005634 nucleus | IEA GO_REF:0000044 | KEEP AS NON CORE | Summary: UniProt subcellular-location mapping (SL-0191 Nucleus), derived from the same Huh et al. GFP data. Retained as non-core for the same reason as the HDA row. Reason: Electronic copy of a high-throughput nuclear signal without a nuclear role. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:14562095}. Nucleus |
| GO:0005737 cytoplasm | HDA PMID:14562095 Global analysis of protein localization in budding yeast. | ACCEPT | Summary: Huh et al. GFP-tagging scored Sol3-GFP in the cytoplasm. This is consistent with a cytosolic oxidative-PPP enzyme. Supporting Evidence: PMID:14562095 We classify these proteins, representing 75% of the yeast proteome, into 22 distinct subcellular localization categories PMID:15454531 Sol3p and Sol4p, which have little or no detectable effect upon los1 suppression or tRNA biogenesis, are located predominantly in the cytosol |
| GO:0005737 cytoplasm | IEA GO_REF:0000044 | ACCEPT | Summary: UniProt subcellular-location mapping (SL-0086 Cytoplasm) for Sol3. Correct. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:14562095}. Nucleus |
| GO:0005829 cytosol | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA (6PGL clade; Arabidopsis cytosolic PGLs and others) placing 6-phosphogluconolactonase as active in the cytosol. Correct for Sol3. Supporting Evidence: PMID:15454531 Sol3p and Sol4p, which have little or no detectable effect upon los1 suppression or tRNA biogenesis, are located predominantly in the cytosol |
| GO:0005829 cytosol | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (OXIDATIVEPENT-PWY) placing the lactonase step in the cytosol. Consistent with Sol3 being predominantly cytosolic. Supporting Evidence: PMID:15454531 Sol3p and Sol4p, which have little or no detectable effect upon los1 suppression or tRNA biogenesis, are located predominantly in the cytosol |
| GO:0005829 cytosol | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (PENTOSE-P-PWY) placing the lactonase step in the cytosol. Consistent with Sol3 being predominantly cytosolic. Supporting Evidence: PMID:15454531 Sol3p and Sol4p, which have little or no detectable effect upon los1 suppression or tRNA biogenesis, are located predominantly in the cytosol |
| GO:0005975 carbohydrate metabolic process | IEA GO_REF:0000002 | MODIFY | Summary: InterPro IPR005900/IPR006148 (6PGL / glucosamine-6-P isomerase family) mapped to carbohydrate metabolic process. Correct but too general; Sol3 acts in the oxidative PPP. Proposed replacements: pentose-phosphate shunt, oxidative branch Supporting Evidence: PMID:15454531 6Pgl (EC 3.1.1.31) catalyzes the second step of the pentose phosphate pathway, the conversion of 6-phosphogluconolactone to 6-phosphogluconate. PMID:15454531 Thus, Sol3p and Sol4p likely function in carbohydrate metabolism |
| GO:0006098 pentose-phosphate shunt | IEA GO_REF:0000120 | ACCEPT | Summary: UniPathway UPA00115 / InterPro IPR005900 mapped to pentose-phosphate shunt. Correct; the more precise oxidative-branch term is also present. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt PATHWAY: Carbohydrate degradation; pentose phosphate pathway; D- |
| GO:0006098 pentose-phosphate shunt | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (PENTOSE-P-PWY) for the pentose-phosphate shunt. Correct for Sol3. Supporting Evidence: PMID:15454531 6Pgl (EC 3.1.1.31) catalyzes the second step of the pentose phosphate pathway, the conversion of 6-phosphogluconolactone to 6-phosphogluconate. |
| GO:0009051 pentose-phosphate shunt, oxidative branch | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA (PTN000114545; donors fly, fission yeast SPCC16C4.10, rat, human PGLS) for the oxidative PPP branch. This is the core process. Supporting Evidence: PMID:15454531 6Pgl (EC 3.1.1.31) catalyzes the second step of the pentose phosphate pathway, the conversion of 6-phosphogluconolactone to 6-phosphogluconate. PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
| GO:0009051 pentose-phosphate shunt, oxidative branch | IC PMID:15454531 Division of labor among the yeast Sol proteins implicated in... | ACCEPT | Summary: Curator inference from Sol3's 6-phosphogluconolactonase activity (GO:0017057), which is the second step of the oxidative PPP. Sound. Supporting Evidence: PMID:15454531 6Pgl (EC 3.1.1.31) catalyzes the second step of the pentose phosphate pathway, the conversion of 6-phosphogluconolactone to 6-phosphogluconate. PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
| GO:0009051 pentose-phosphate shunt, oxidative branch | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (OXIDATIVEPENT-PWY) for the oxidative PPP branch. Correct. Supporting Evidence: PMID:15454531 6Pgl (EC 3.1.1.31) catalyzes the second step of the pentose phosphate pathway, the conversion of 6-phosphogluconolactone to 6-phosphogluconate. |
| GO:0017057 6-phosphogluconolactonase activity | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA (PTN000114545) for 6-phosphogluconolactonase activity. Sol3 belongs to the catalytically active Sol3/Sol4 branch. The Sol1/Sol2 paralogs lack detectable activity and should not inherit this term. Supporting Evidence: PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels file:yeast/SOL3/SOL3-uniprot.txt Reaction=6-phospho-D-glucono-1,5-lactone + H2O = 6-phospho-D-gluconate |
| GO:0017057 6-phosphogluconolactonase activity | IEA GO_REF:0000120 | ACCEPT | Summary: EC 3.1.1.31 / RHEA:12556, InterPro IPR005900 and ARBA mapped to 6-phosphogluconolactonase activity. Correct for Sol3, although the same InterPro mapping would wrongly hit the inactive Sol1/Sol2 paralogs. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt Reaction=6-phospho-D-glucono-1,5-lactone + H2O = 6-phospho-D-gluconate PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
| GO:0017057 6-phosphogluconolactonase activity | IGI PMID:15454531 Division of labor among the yeast Sol proteins implicated in... | ACCEPT | Summary: Stanford et al. deleted all four SOL genes, which left very low 6Pgl activity. Supplying SOL3 (or SOL4, SGD:S000003480) on a multicopy plasmid restored activity beyond wild type, whereas SOL1 or SOL2 did not. This establishes Sol3 as a 6-phosphogluconolactonase, redundant with Sol4. Supporting Evidence: PMID:15454531 Compared to the wild-type strain (X2316-3C) containing the vector pRS426, the strain with the entire SOL family deleted (MLW115) containing pRS426 had very low, if any, 6Pgl activity. PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
| GO:0017057 6-phosphogluconolactonase activity | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (OXIDATIVEPENT-PWY) assigning 6-phosphogluconolactone hydrolysis (EC 3.1.1.31) to Sol3. Correct. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt Reaction=6-phospho-D-glucono-1,5-lactone + H2O = 6-phospho-D-gluconate PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
| GO:0017057 6-phosphogluconolactonase activity | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways RCA (PENTOSE-P-PWY) assigning 6-phosphogluconolactone hydrolysis (EC 3.1.1.31) to Sol3. Correct. Supporting Evidence: file:yeast/SOL3/SOL3-uniprot.txt Reaction=6-phospho-D-glucono-1,5-lactone + H2O = 6-phospho-D-gluconate PMID:15454531 In contrast, cells containing multi-copy plasmids with SOL3 or SOL4 provided activity beyond wild-type levels |
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6-phosphogluconolactonase; catalyzes the second step of the pentose phosphate pathway; weak multicopy suppressor of los1-1 mutation; homologous to Sol2p and Sol1p; SOL3 has a paralog, SOL4, that arose from the whole genome duplication
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