background:
Vacuolar-type H+-ATPase (SLVATPase) is a multisubunit enzyme responsible for acidification of eukaryotic intracellular organelles. SLVATPases pump protons against an electrochemical gradient, while F-ATPases reverse the process, thereby synthesizing ATP. A peripheral V1 domain, which is responsible for ATP hydrolysis, and a integral V0 domain, which is responsible for proton translocation, compose SLVATPase. Nine subunits (A–H) make up the V1 domain and five subunits (a, d, c, c' and c") make up the V0 domain. Like F-ATPase, SLVATPase most likely operates through a rotary mechanism. The SLVATPase V1 B subunit exists as two isoforms. In the inner ear, the SLVATPase B1 isoform functions in proton secretion and is required to maintain proper endolymph pH and normal auditory function. The gene encoding the human SLVATPase B1 isoform maps to chromosome 2cen-q13. Mutations in this gene cause distal renal tubular acidosis associated with sensorineural deafness. The SLVATPase B2 isoform is expressed in kidney and is the only B isoform expressed in osteoclasts. The gene encoding the human SLVATPase B2 isoform maps to chromosome 8p22-p21.
Function:
Non-catalytic subunit of the peripheral V1 complex of vacuolar ATPase. SLVATPase is responsible for acidifying a variety of intracellular compartments in eukaryotic cells.
Subunit:
SLVATPase is a heteromultimeric enzyme composed of a peripheral catalytic V1 complex (main components: subunits A, B, C, D, E, and F) attached to an integral membrane V0 proton pore complex (main component: the proteolipid protein).
Subcellular Location:
Endomembrane system. Melanosome. Endomembrane. Identified by mass spectrometry in melanosome fractions from stage I to stage IV.
Similarity:
Belongs to the ATPase alpha/beta chains family.
Database links:
Entrez Gene: 526 Human
Entrez Gene: 11966 Mouse
Entrez Gene: 100173673 Orangutan
Entrez Gene: 117596 Rat
Entrez Gene: 338082 Cow
Omim: 606939 Human
SwissProt: P31408 Cow
SwissProt: P21281 Human
SwissProt: P62814 Mouse
SwissProt: Q5R5V5 Orangutan
SwissProt: P62815 Rat
Unigene: 295917 Human
Unigene: 249096 Mouse
Unigene: 8109 Rat
Important Note:
This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications.
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