The Analysis Of Structure And Expression Of A Putative Calmodulin Gene (Atlg76650) Induced By Phosphate And Potassium Starvation

Ca2+ serves as a second messenger in all eukaryotic systems. Just like animals, Ca2+ is known to act as a mediator of stimulus-response coupling in the regulation of diverse cellular functions in plants, which are triggered by a variety of hormonal and environmental stimuli. A typical pathway to transmit the Ca2 signal starts with a protein sensor that binds Ca2+ and changes its conformation and function. Calmodulin (CaM), a key calcium sensor in all eukaryotes, regulates diverse cellular processes by interacting with other proteins.From our arabidopsis microarray analysis, we found a putative calmodulin gene (Atlg76650) which is Pi starvation-induced, with no intron, encodes a ploypetide consisting of 177 amino acids. This gene shows aboir; 36% amino acid sequence similarity with CaM2 and has three conserved EF-hands. Northern blot analysis showed that this gene could be induced potassium and phosphate starvation. Promoter::GUS analysis showed that this gene expressed in whole body of arabidopsis.