Protein modeling and evolutionary analysis of Calmodulin Binding Transcription Activator (CAMTA) gene family in Sorghum bicolor

Calmodulin Binding Transcription Activator (CAMTA) family is present in almost all plants and in many animals. CAMTA are named so due to the presence of specific calmodulin binding domain which is an important Ca2+ transducer. Multiple sequence alignment and phylogenetic analysis of CAMTA proteins in Sorghum bicolor, Oryza sativa, Zea mays, Glycine max and Arabidopsis thaliana showed highly conserved sequence and evolutionary similarity. In Sorghum bicolor six CAMTA proteins were identified to be located in nucleus. These proteins were named on the basis of their location on the chromosomes. Alignment and phylogenetic tree clearly indicates close similarity in monocot and dicot ancestry which appears on the same clade but diverged from each other with time. Almost all CAMTA proteins share same domain organizations. A highly conserved motif sequence in these species was identified which might play some important functional roles. In order to understand structural and DNA binding patterns of SbCAMTA proteins, 3-D models of proteins structure and their domains revealed many important DNA binding residues playing their role in protein-protein interaction and structural modification.. A further detailed study of the CAMTA protein members in sorghum may explore their mode of interaction and exact function in signaling mechanism under abiotic stresses.