Cloning and in silico analysis of a gene encoding a putative β-carbonic anhydrase from cowpea (Vigna unguiculata L. Walp)

Abstract

A gene encoding putative β-carbonic anhydrase gene (CA) from cowpea (Vigna unguiculata L. Walp.) was characterized and designated as VuCA1 (GenBank ID: JQ429799). While the genomic sequence of CA was found to be 1470 bp long with 4 introns, the open reading frame was 990 bp in length. The deduced amino acid sequence of CA contained two characteristic conserved domains, i.e. CSDSRV and EYAVLHLKVSNIVVIGHSACG, which showed high degree of homology with other β-CA genes of angiosperms. We have reported three-dimensional model of VuCA1 and quality of the predicted model was analysed with PROCHECK. Molecular docking of modeled VuCA1 revealed similar binding pockets for different substrates and products. The expression of VuCA1 transcripts was detected in different parts of the cowpea plant, with highest level observed in leaves, followed by flower buds, weak expression in stems, and the weakest in roots. The expression of VuCA1 transcripts of leaves was downregulated by zinc deficiency but upregulated by salt and dehydration stress.

Keywords:

• abiotic stress
• allele mining
• carbonic anhydrase
• Vigna unguiculata (L.) Walp
• zinc deficiency

Acknowledgments

The authors are grateful to Dr Neeta Singh, Principle Scientist, Division of Germplam Conservation, NBPGR, New Delhi, for providing the seeds and related information of cowpea to carry out the experiment. We also thank Dr K V Bhat, Head, Division of Genomic Resource, NBPGR, for his encouragement to carry out this work.