The vacuolar Ca2+/H+ exchanger Vcx1p/Hum1p tightly controls cytosolic Ca2+ levels in S. cerevisiae

FEBS Lett. 1999 May 21;451(2):132-6. doi: 10.1016/s0014-5793(99)00519-0.


It is well established that the vacuole plays an important role in the cellular adaptation to growth in the presence of elevated extracellular Ca2+ concentrations in Saccharomyces cerevisiae. The Ca2+ ATPase Pmc1p and the Ca2+/H+ exchanger Vcx1p/Hum1p have been shown to facilitate Ca2+ sequestration into the vacuole. However, the distinct physiological roles of these two vacuolar Ca2+ transporters remain uncertain. Here we show that Vcx1p can rapidly sequester a sudden pulse of cytosolic Ca2+ into the vacuole, while Pmc1p carries out this function much less efficiently. This finding is consistent with the postulated role of Vcx1p as a high capacity, low affinity Ca2+ transporter and suggests that Vcx1p may act to attenuate the propagation of Ca2+ signals in this organism.

MeSH terms

  • Aequorin / metabolism
  • Anti-Bacterial Agents / pharmacology
  • Antiporters / physiology*
  • Calcium / metabolism*
  • Calcium-Binding Proteins / physiology*
  • Calcium-Transporting ATPases / physiology
  • Cation Transport Proteins*
  • Cytosol / metabolism*
  • Enzyme Inhibitors / pharmacology
  • Fungal Proteins / physiology
  • Ion Exchange*
  • Macrolides*
  • Mutagenesis
  • Plasma Membrane Calcium-Transporting ATPases
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins*
  • Time Factors
  • Vacuoles / metabolism*


  • Anti-Bacterial Agents
  • Antiporters
  • Calcium-Binding Proteins
  • Cation Transport Proteins
  • Enzyme Inhibitors
  • Fungal Proteins
  • Macrolides
  • PMC1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • VCX1 protein, S cerevisiae
  • calcium-hydrogen antiporters
  • Aequorin
  • bafilomycin A1
  • Plasma Membrane Calcium-Transporting ATPases
  • Calcium-Transporting ATPases
  • Calcium