Comparative Molecular Biological Analysis of Rice Calcium Signal Transduction Genes Based on Full-length cDNA Data

Abstract

We have obtained 28K full-length cDNA sequence data from the rice full-length cDNA project and homology search was made against NCBI GenBank data. Comparative analysis of calcium ion transporter protein revealed that, the cell-to-cell calcium signal transduction systems(the voltage dependent calcium channel, Ins3 receptor and ryanodine receptor etc.) have severely changed between animal and plant. On the other hand, signal transduction systems at the internal of the individual cells (animal Ligand-gated channel protein, Ca2+ATPase, Ion-exchanger membrane proteins) are well conserved between plant and animal. Comparative analyses of calcium ion binding and/or controlling signal transduction protein were also carried out. It revealed that, plant developed directly calcium ion interacting system more than animal. There are many species of plant specific calcium ion binding protein, which has calcium ion binding domain (EF-hand) plus CAMK II type kinase domain (CDPK) or phosphates domain (PP2B) or Ca2+ /phospholipid binding domain.