|Protein Name||V-type proton ATPase subunit H|
|Ref Sequence Id||NP_777129.2|
|Amino Acid Lenth||483|
|Protein Existence Status||Reviewed: Experimental evidence at transcript level|
|Presence in other biological fluids/tissue/cells||ubiquitous in eukaryotes, distributed mostly on intracellular tubulo-vesicular membranes, but found also at the plasma membrane in specialized cell types|
|Protein Function||primarily responsible for the establishment and maintenance of the acidic pH of endocytic and secretory organelles, pumping cytosolic H+ into their lumen in an ATP-dependent manner; Plasmalemmal V-ATPase function in renal cells is important for the systemic acid-base balance, through secretion of acid into the urine; Activated neutrophils and macrophages use plasma membrane V-ATPases to maintain a neutral cytoplasmic pH;|
|Biochemical Properties||The V- are multisubunit proteins of up to 14 different polypeptides, which assemble as two major ring structures: (1) a peripheral V1 complex that interacts with ATP, ADP and inorganic phosphate, and (2) an integral membrane V0 complex that is membrane embedded mediates the transport of H+ or Na+; V-ATPase is largely responsible for the accumulation of H+ in endocytic vesicles; H+ pumping by VATPases accounts for the uniquely acidic lysosomal pH of ,4.5 that is essential for optimal enzyme function;|
|Bibliography||1. Brown, D., & Breton, S. (2000). H(+)V-ATPase-dependent luminal acidification in the kidney collecting duct and the epididymis/vas deferens: vesicle recycling and transcytotic pathways. The Journal of Experimental Biology, 203(Pt 1), 137–145. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/10600682. |
2. Hirata, T., Nakamura, N., Omote, H., Wada, Y., & Futai, M. (2000). Regulation and reversibility of vacuolar H(+)-ATPase. The Journal of Biological Chemistry, 275(1), 386–389. https://doi.org/10.1074/jbc.275.1.386.
3. Huynh, K. K., & Grinstein, S. (2007). Regulation of vacuolar pH and its modulation by some microbial species. Microbiology and Molecular Biology Reviews : MMBR, 71(3), 452–462. https://doi.org/10.1128/MMBR.00003-07.
4. Brisseau, G. F., Grinstein, S., Hackam, D. J., Nordström, T., Manolson, M. F., Khine, A. A., & Rotstein, O. D. (1996). Interleukin-1 increases vacuolar-type H+-ATPase activity in murine peritoneal macrophages. The Journal of Biological Chemistry, 271(4), 2005–2011. https://doi.org/10.1074/jbc.271.4.2005.