Functional analysis of a rice putative voltage-dependent Ca2+ channel, OsTPC1, expressed in yeast cells lacking its homologous gene CCH1

Plant Cell Physiol. 2004 Apr;45(4):496-500. doi: 10.1093/pcp/pch053.


We isolated a cDNA (OsTPC1) from rice that was homologous to AtTPC1, a putative voltage-dependent Ca(2+) channel (VDCC) gene of Arabidopsis thaliana. The hydropathy profile of its deduced amino acid sequence showed significant structural features of the alpha 1-subunit of animal VDCCs. Functional analysis using a heterologous yeast expression system showed that OsTPC1 facilitates Ca(2+) permeation. The K(m) value for Ca(2+) of OsTPC1, 47.5 micro M, was comparable to that of intrinsic CCH1, a candidate VDCC in yeast. Ca(2+) permeation by OsTPC1 was inhibited by verapamil, a VDCC blocker. These findings indicate for the first time that OsTPC1 is a putative VDCC in rice.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Calcium / metabolism
  • Calcium Channels / genetics*
  • Calcium Channels / metabolism
  • Cells, Cultured
  • Culture Media
  • Gene Expression
  • Molecular Sequence Data
  • Oryza / genetics*
  • Oryza / metabolism
  • Plant Proteins / genetics
  • Saccharomyces cerevisiae Proteins / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Yeasts / cytology
  • Yeasts / genetics


  • CCH1 protein, S cerevisiae
  • Calcium Channels
  • Culture Media
  • Plant Proteins
  • Saccharomyces cerevisiae Proteins
  • Calcium