Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
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VMA22 IBA annotations derive from family-transfer context and are strongest for Vma12-Vma22 complex membership; unfolded protein binding is too broad.
"GOA WITH/FROM includes PANTHER evidence for GO:1990871 Vma12-Vma22 assembly complex and GO:0051082 unfolded protein binding."
UniProtKB entry for VMA22_YEAST
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Vma22 is required for V-ATPase activity and has two UniProt alternative initiation isoforms.
"FUNCTION: Required for V-ATPase activity. ALTERNATIVE PRODUCTS: Event = Alternative initiation; Named isoforms = 2."
Genes required for vacuolar acidity in Saccharomyces cerevisiae
One library to make them all: streamlining the creation of yeast libraries via a SWAp-Tag strategy
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The localization library used visual assignments without co-localization markers; the cached main text does not identify VMA22's individual score.
"Since no co-localization markers were used we only assigned localizations that could be easily discriminated by eye: ER, nuclear periphery, cytosol, cell periphery, vacuole lumen, vacuole membrane, mitochondria, nucleus, bud/bud neck and punctate"
Vma22p is a novel endoplasmic reticulum-associated protein required for assembly of the yeast vacuolar H(+)-ATPase complex
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Vma22 is ER-associated and required for V-ATPase assembly but is not a subunit of the mature V-ATPase.
"Vma22p is a 21-kDa hydrophilic protein that is not a subunit of the V-ATPase but rather is associated with ER membranes."
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Loss of VMA22 blocks V-ATPase complex assembly and activity.
"vma22 delta cells contain no V-ATPase activity due to a failure to assemble the enzyme complex."
vph6 mutants of Saccharomyces cerevisiae require calcineurin for growth and are defective in vacuolar H(+)-ATPase assembly
Assembly of the yeast vacuolar H+-ATPase occurs in the endoplasmic reticulum and requires a Vma12p/Vma22p assembly complex
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Vma12 and Vma22 form a stable ER-associated complex that transiently interacts with Vph1 during V-ATPase assembly.
"Vma12p and Vma22p form a stable membrane associated complex. Cross-linking analysis also revealed a direct physical interaction between the Vma12p/Vma22p assembly complex and Vph1p."
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Vma22 is a dedicated assembly factor, not a general molecular chaperone.
"Unlike general molecular chaperones such as Kar2p/BiP (Gething and Sambrook, 1992), Vma12p, Vma21p, and Vma22p represent a class of ER resident proteins dedicated to the assembly of a specific enzyme complex, the V-ATPase."
Structural basis of V-ATPase V(O) region assembly by Vma12p, 21p, and 22p.
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Vma12-Vma22p recruits V0 subunits during ER-stage assembly and prevents premature V1 association.
"Electron cryomicroscopy shows how the Vma12-22p complex recruits subunits a, e, and f to the rotor ring of VO while blocking premature binding of V1."
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The resolved Vma22p structure predicts that it blocks premature V1 attachment to partially assembled V0 complexes in the ER.
"Thus, the structure of Vma22p suggests that it would block V1 from binding subunit d, which would prevent premature attachment of V1 to partially assembled VO complexes in the ER membrane."
Falcon deep research report for VMA22
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Falcon supports Vma22 as an ER-associated V-ATPase V0-region assembly factor and not a general unfolded-protein binding protein.
"**VMA22 (P38784/YHR060W)** encodes **Vma22p**, an **ER-associated peripheral assembly factor** required for **V-ATPase V0-region biogenesis**."