Handling calcium signaling: Arabidopsis CaMs and CMLs.
The Arabidopsis genome harbors seven calmodulin (CAM) and 50 CAM-like (CML) genes that encode potential calcium sensors. The CAMs encode only four protein isoforms. Selective pressure to maintain multiple CAMs indicates nonredundancy. Sequence divergence, even in the EF hand calcium-binding motif, exists among the CMLs and, therefore, divergent functions are likely to have evolved. Expression data recently available from Massively Parallel Signature Sequencing and Genevestigator compilation of microarrays are reviewed. The seven Arabidopsis CAMs are highly and relatively uniformly expressed. Differential expression is evident among the distinct CMLs over developmental stages, in various organs and in response to many different stimuli. In spite of the potential importance in mediating plant calcium signaling, the physiological functions of the Arabidopsis CaMs and CMLs remain largely unknown.
McCormack
Elizabeth
E
Biochemistry and Cell Biology, Rice University, Houston, TX 77005-1892, USA.
Tsai
Yu-Chang
YC
Braam
Janet
J
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology*; D002147:Calmodulin / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D017124:Conserved Sequence; D018745:Genome, Plant; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D029681:Arabidopsis Proteins; D002147:Calmodulin; D020033:Protein Isoforms