Induction of vacuolar Ca2+-ATPase and H+/Ca2+ exchange activity in yeast mutants lacking Pmr1, the Golgi Ca2+-ATPase.
We have analyzed Ca2+ transport activity in defined subcellular fractions of an isogenic set of wild-type and mutant yeast. The results, together with measurements of polypeptide expression levels and promoter::reporter gene activity, show that the Golgi Ca2+-ATPase, Pmr1, is the major Ca2+ pump under normal growth conditions. In the absence of Pmr1, we show a massive, calcineurin-dependent compensatory induction of the vacuolar Ca2+-ATPase, Pmc1. In addition, H+/Ca2+ exchange activity, that may be distinct from the vacuolar exchanger Vcx1, is also increased.
Marchi
V
V
Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Sorin
A
A
Wei
Y
Y
Rao
R
R
D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism; D017136:Ion Transport; D018832:Molecular Chaperones; D012441:Saccharomyces cerevisiae / Q000378:metabolism* / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins
D018528:ATP-Binding Cassette Transporters; D018832:Molecular Chaperones; C101767:SSC1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D006859:Hydrogen; D000252:Calcium-Transporting ATPases; D002118:Calcium