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==Funcións das ATPases V==
As ATPases V encóntranse nas membranas de moitos orgánulos, como os [[endosoma]]s, [[lisosoma]]s, e [[vesícula]]s secretoras, nos que desempeñan diversas funcións esenciais para o funcionamento deses orgánulos. Por exemplo, o gradiente de protóns a través da membrana vacuolar dos lévedos xerado por estas ATPases dirixe a captación de calcio ao interior dos [[vacúolo]]s por medio dun sistema antiportador de H<sup>+</sup>/Ca<sup>2+</sup> (<ref name=Ohya91>{{cite journal |author=Ohya Y, Umemoto N, Tanida I, Ohta A, Iida H, Anraku Y |title=Calcium-sensitive cls mutants of Saccharomyces cerevisiae showing a Pet- phenotype are ascribable to defects of vacuolar membrane H<sup>+</sup>-ATPase activity |journal=J. Biol. Chem. |volume=266 |issue=21 |pages=13971–7 |year=1991) |month=July |pmid=1830311 |url=http://www.jbc.org/cgi/pmidlookup?view=long&pmid=1830311}}</ref>. Na transmisión [[sinapse|sináptica]] das [[neurona]]s, as ATPases V acidifican as vesículas sinápticas.<ref>{{cite journal |author=Wienisch M, Klingauf J |title=Vesicular proteins exocytosed and subsequently retrieved by compensatory endocytosis are nonidentical |journal=Nat. Neurosci. |volume=9 |issue=8 |pages=1019–27 |date=August 2006 |pmid=16845386 |doi=10.1038/nn1739 }}</ref>
As ATPases vacuolares tamén se encontran nas [[membrana plasmática|membranas plasmáticas]] dunha ampla variedade de células como as [[célula intercada|células intercaladas]] dos [[ril]]es, [[osteoclasto]]s (células que reabsorben o óso), [[macrófago]]s, [[neutrófilo]]s, [[espermatozoide]]s, células do intestino medio de [[insecto]]s, e certas células [[tumor]]ais.<ref>{{cite journal |author=Izumi H |title=Cellular pH regulators: potentially promising molecular targets for cancer chemotherapy |journal=Cancer Treat. Rev. |volume=29 |issue=6 |pages=541–9 |date=December 2003 |pmid=14585264 |url=http://linkinghub.elsevier.com/retrieve/pii/S0305737203001063 |doi=10.1016/S0305-7372(03)00106-3|author-separator= |author2= Torigoe T |author3= Ishiguchi H |author4=and others |displayauthors=3 }}</ref> As ATPases V da membrana plasmática están implicadas en procesos como a [[homeostase]] do [[pH]], [[Cotransporte|transporte acoplado]], e [[metástase]] tumoral. As ATPases V na membrana do [[acrosoma]] do espermatozoide acidifican o acrosoma. Esta acidificación activa as [[protease]]s necesarias para a perforación da membrana do ovo durante a fecundación. As ATPases V da membrana plasmática dos osteoclastos bombean protóns á superficie do [[tecido óseo]], o cal é necesario para a reabsorción ósea. Nas células intercaladas dos riles, estas ATPases bombean protóns á [[urina]], permitindo a reabsorción de [[bicarbonato]] ao sangue.
===Acidose tubular renal distal===
A importancia da actividade da ATPase V na secreción renal de protóns está suliñada pola enfermidade hereditaria [[acidose tubular renal]] distal. En todos os casos, a acidose tubular renal orixínase polo fallo dos mecanismos renais normais que regulan o pH sistémico. Hai catro tipos de acidose tubular renal. O tipo 1 é a acidose tubular renal distal e orixínase polo fallo no [[conduto colector cortical]] para acidificar o pH da [[urina]] por debaixo de 5. <ref name=Alper02>{{cite journal |author=Alper, SL |title=Genetic diseases of acid-base transporters |journal=Annu. Rev. Physiol. |volume=64 |issue= |pages=899–923 |year=2002} |pmid=11826292 |doi=10.1146/annurev.physiol.64.092801.141759 |doi=10.1146/annurev.physiol.64.092801.141759?url_ver=Z39.88-2003}}</ref> Algúns pacientes con acidose tubular renal distal autosómica recesiva tamén presentan unha [[xordeira sensorineural]].<ref name=Karet99>{{cite journal |author=Karet, FE |title=Mutations in the gene encoding B1 subunit of H<sup>+</sup>-ATPase cause renal tubular acidosis with sensorineural deafness |journal=Nat. Genet. |volume=21 |issue=1 |pages=84–90 |year=1999 |month=January |pmid=9916796 |doi=10.1038/5022 |author-separator= |author2= Finberg KE |author3= Nelson RD |author4=and others |displayauthors=3 }}</ref>. A herdanza deste tipo de acidose tubular renal depende de mutacións na subunidade isoforma B1 da ATPase V ou na isoforma a4 ou mutacións da [[banda 3]] (tamén chamada AE1), un intercambiador Cl<sup>-</sup>/HCO3<sup>-</sup> {Stehberger, 2003;<ref Karet,name=Karet99/> 1999;<ref name=Karet98>{{cite journal |author=Karet, FE |title=Mutations in the chloride-bicarbonate exchanger gene AE1 cause autosomal dominant but not autosomal recessive distal renal tubular acidosis |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=95 |issue=11 |pages=6337–42 |date=May 1998 |pmid=9600966 |pmc=27686 |url=http://www.pnas.org/cgi/pmidlookup?view=long&pmid=9600966 |bibcode=1998PNAS...95.6337K |last2=Gainza |last3=Gyory |last4=Unwin |last5=Wrong |last6=Tanner |last7=Nayir |last8=Alpay |last9=Santos |doi=10.1073/pnas.95.11.6337|author-separator= |displayauthors=3 |last10=Hulton |first10=S. A. |last11=Bakkaloglu |first11=A. |last12=Ozen |first12=S. |last13=Cunningham |first13=M. J. |last14=Di Pietro |first14=A. |last15=Walker |first15=W. G. |last16=Lifton |first16=R. P. }}</ref>. Sábese que hai doce mutacións diferentes na isoforma B1 da ATPase V (Stover,<ref 2002)name=Stover02/> e vinte e catro mutacións na a4 que orixinan a acidose tubular renal distal. {Smith, 2000; Karet,<ref 1999;name=Karet99/><ref name=Stover05>{{cite journal |author=Stover, 2005}EH |title=Novel ATP6V1B1 and ATP6V0A4 mutations in autosomal recessive distal renal tubular acidosis with new evidence for hearing loss |journal=J. Med. Genet. |volume=39 |issue=11 |pages=796–803 |date=November 2002 |pmid=12414817 |pmc=1735017 |url=http://jmg.bmj.com/cgi/pmidlookup?view=long&pmid=12414817 |doi=10.1136/jmg.39.11.796|author-separator= |author2= Borthwick KJ |author3= Bavalia C |author4=and others |displayauthors=3 }}</ref> Os estudos de [[PCR]] e [[transcrición inversa]] mostraron a expresión da subunidade a4 nas células intercaladas renais e na [[cóclea]] do oído {Stover, 2002}. A acidose tubular renal distal causada por mutacións no xene da subunidade a4 nalgúns casos pode asociarse coa xordeira debido ao fallo na acidificación normal da [[endolinfa]] do [[oído interno]].<ref name=Stehberger03>{{cite journal |author=Stehberger, PA |title=Localization and regulation of the ATP6V0A4 (a4) vacuolar H<sup>+</sup>-ATPase subunit defective in an inherited form of distal renal tubular acidosis |journal=J. Am. Soc. Nephrol. |volume=14 |issue=12 |pages=3027–38 |year=2003} |month=December |pmid=14638902 |url=http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=14638902 |doi=10.1097/01.ASN.0000099375.74789.AB|author-separator= |author2= Schulz N |author3= Finberg KE |author4=and others |displayauthors=3 }}</ref>
==Nomenclatura==
*[[ATPase F]]
*[[ATPase Na+/K+]]
===Outras lecturas===
*{{cite journal |author=Alper SL |title=Genetic diseases of acid-base transporters |journal=Annu. Rev. Physiol. |volume=64 |issue= |pages=899–923 |year=2002 |pmid=11826292 |doi=10.1146/annurev.physiol.64.092801.141759 |doi=10.1146/annurev.physiol.64.092801.141759?url_ver=Z39.88-2003}}
*{{cite journal |author=Karet FE |title=Mutations in the chloride-bicarbonate exchanger gene AE1 cause autosomal dominant but not autosomal recessive distal renal tubular acidosis |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=95 |issue=11 |pages=6337–42 |date=May 1998 |pmid=9600966 |pmc=27686 |url=http://www.pnas.org/cgi/pmidlookup?view=long&pmid=9600966 |bibcode=1998PNAS...95.6337K |last2=Gainza |last3=Gyory |last4=Unwin |last5=Wrong |last6=Tanner |last7=Nayir |last8=Alpay |last9=Santos |doi=10.1073/pnas.95.11.6337|author-separator= |displayauthors=3 |last10=Hulton |first10=S. A. |last11=Bakkaloglu |first11=A. |last12=Ozen |first12=S. |last13=Cunningham |first13=M. J. |last14=Di Pietro |first14=A. |last15=Walker |first15=W. G. |last16=Lifton |first16=R. P. }}
*{{cite journal |author=Karet FE |title=Mutations in the gene encoding B1 subunit of H<sup>+</sup>-ATPase cause renal tubular acidosis with sensorineural deafness |journal=Nat. Genet. |volume=21 |issue=1 |pages=84–90 |year=1999 |month=January |pmid=9916796 |doi=10.1038/5022 |author-separator= |author2= Finberg KE |author3= Nelson RD |author4=and others |displayauthors=3 }}
*{{cite journal |author=Ohya Y, Umemoto N, Tanida I, Ohta A, Iida H, Anraku Y |title=Calcium-sensitive cls mutants of Saccharomyces cerevisiae showing a Pet- phenotype are ascribable to defects of vacuolar membrane H<sup>+</sup>-ATPase activity |journal=J. Biol. Chem. |volume=266 |issue=21 |pages=13971–7 |year=1991 |month=July |pmid=1830311 |url=http://www.jbc.org/cgi/pmidlookup?view=long&pmid=1830311}}
*{{cite journal |author=Stehberger PA |title=Localization and regulation of the ATP6V0A4 (a4) vacuolar H<sup>+</sup>-ATPase subunit defective in an inherited form of distal renal tubular acidosis |journal=J. Am. Soc. Nephrol. |volume=14 |issue=12 |pages=3027–38 |year=2003 |month=December |pmid=14638902 |url=http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=14638902 |doi=10.1097/01.ASN.0000099375.74789.AB|author-separator= |author2= Schulz N |author3= Finberg KE |author4=and others |displayauthors=3 }}
*{{cite journal |author=Stover EH |title=Novel ATP6V1B1 and ATP6V0A4 mutations in autosomal recessive distal renal tubular acidosis with new evidence for hearing loss |journal=J. Med. Genet. |volume=39 |issue=11 |pages=796–803 |date=November 2002 |pmid=12414817 |pmc=1735017 |url=http://jmg.bmj.com/cgi/pmidlookup?view=long&pmid=12414817 |doi=10.1136/jmg.39.11.796|author-separator= |author2= Borthwick KJ |author3= Bavalia C |author4=and others |displayauthors=3 }}
=== Ligazóns externas ===
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