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The ubiquitous 14 subunit vacuolar H+-ATPase, V1/V0, has been implicated in various human diseases including osteopetrosis, renal tubule acidosis, and cancer (Hinton et al., 2009).  The transmembrane enzyme, Ribonuclease kappa, RNASEK (137 aas; 2 TMSs; UniProt acc# Q6P5S7), closely associates with the V-ATPase and is required for its function; its loss prevents the early events of endocytosis and the replication of multiple pathogenic viruses (Perreira et al. 2015).  Cryo-EM allowed the construction of an atomic model, defining the enzyme's ATP:proton ratio as 3:10 and revealing a homolog of yeast subunit f in the membrane region, which appeared to be RNAseK (Abbas et al. 2020). The c ring encloses the transmembrane anchors for cleaved ATP6AP1/Ac45 and ATP6AP2/PRR, the latter of which is the (pro)renin receptor that, in other contexts, is involved in both Wnt signaling and the renin-angiotensin system that regulates blood pressure. This structure shows how ATP6AP1/Ac45 and ATP6AP2/PRR enable assembly of the enzyme's catalytic and membrane regions (Abbas et al. 2020).

Accession Number:Q96LB4
Protein Name:V-ATPase subunit G3
Molecular Weight:13917.00
Species:Homo sapiens (Human) [9606]
Location1 / Topology2 / Orientation3: Endomembrane system1 / Peripheral membrane protein2
Substrate H+

Cross database links:

Genevestigator: Q96LB4
eggNOG: prNOG20768
RefSeq: NP_573569.1    NP_579872.1   
Entrez Gene ID: 127124   
Pfam: PF03179   
Drugbank: Drugbank Link   
KEGG: hsa:127124   

Gene Ontology

GO:0005829 C:cytosol
GO:0005886 C:plasma membrane
GO:0016471 C:vacuolar proton-transporting V-type ATPase ...
GO:0051117 F:ATPase binding
GO:0016820 F:hydrolase activity, acting on acid anhydrid...
GO:0015992 P:proton transport

References (3)

[1] “Molecular cloning and characterization of novel tissue-specific isoforms of the human vacuolar H(+)-ATPase C, G and d subunits, and their evaluation in autosomal recessive distal renal tubular acidosis.”  Smith   12384298
[2] “The DNA sequence and biological annotation of human chromosome 1.”  Gregory   16710414
[3] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project   15489334

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FASTA formatted sequence