Knockdown of V-ATPase subunit A (atp6v1a) impairs acid secretion and ion balance in zebrafish (Danio rerio).
In the skin of zebrafish embryo, the vacuolar H(+)-ATPase (V-ATPase, H(+) pump) distributed mainly in the apical membrane of H(+)-pump-rich cells, which pump internal acid out of the embryo and function similarly to acid-secreting intercalated cells in mammalian kidney. In addition to acid excretion, the electrogenic H(+) efflux via the H(+)-ATPases in the gill apical membrane of freshwater fish was proposed to act as a driving force for Na(+) entry through the apical Na(+) channels. However, convincing molecular physiological evidence in vivo for this model is still lacking. In this study, we used morpholino-modified antisense oligonucleotides to knockdown the gene product of H(+)-ATPase subunit A (atp6v1a) and examined the phenotype of the mutants. The H(+)-ATPase knockdown embryos revealed several abnormalities, including suppression of acid-secretion from skin, growth retardation, trunk deformation, and loss of internal Ca(2+) and Na(+). This finding reveals the critical role of H(+)-ATPase in embryonic acid -secretion and ion balance, as well.
Horng
Jiun-Lin
JL
Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan, ROC.
Lin
Li-Yih
LY
Huang
Chang-Jen
CJ
Katoh
Fumi
F
Kaneko
Toyoji
T
Hwang
Pung-Pung
PP
D000143:Acids / Q000378:metabolism*; D000818:Animals; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D005618:Fresh Water; D015971:Gene Expression Regulation, Enzymologic; D009154:Mutation; D021122:Protein Subunits / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D011522:Protons; D025262:Vacuolar Proton-Translocating ATPases / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D014882:Water-Electrolyte Balance; D015017:Yolk Sac / Q000378:metabolism; D015027:Zebrafish / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*
D000143:Acids; D021122:Protein Subunits; D011522:Protons; D029961:Zebrafish Proteins; C520788:V-ATPase subunit A, zebrafish; D025262:Vacuolar Proton-Translocating ATPases; D006180:Proton-Translocating ATPases