Induction of vacuolar CaZ+-ATPase and H+/Ca 2+ exchange activity in yeast mutants lacking Pmrl, the Golgi Ca2+-ATPase
نویسندگان
چکیده
We have analyzed Ca 2+ 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 CaZ+-ATPase, Pmrl, is the major Ca 2+ pump under normal growth conditions. In the absence of Pmrl, we show a massive, calcineurin-dependent compensatory induction of the vacuolar Ca2+-ATPase, Pmcl. In addition, H+/Ca 2+ exchange activity, that may be distinct from the vacuolar exchanger Vcxl , is also increased. © 1999 Federation of European Biochemical Societies.
منابع مشابه
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 com...
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