Isolation, Characterization and Expression Analysis of Hordeumvulgare 22 (HVA 22) Gene from Drought Tolerant Sugarcane Variety

Abstract

Sugarcane is an important commercial crop in India. Water deficit stress is the major limitation for sustainable sugarcane production across the country. Owing to its socio-economic importance, predicted climate changes and increase in the possibility of water shortage, a drought responsive geneHordeumvulgare 22 (HVA 22) was cloned and characterized from drought tolerant sugarcane variety Co 740. The open reading frame of this gene is 945 bp that encodes for a single polypeptide of 314 amino acids. In silico analysis of HVA 22 using bioinformatics tools revealed the ~ 35.56 kDA size protein with theoretical pI 9.17, instability index 38.70, aliphatic index 66.53 and GRAVY of -0.742. Subcellular localization by WOLFPSORT server suggested that HVA 22 expression is localized in the nucleus, mitochondria and chloroplast. TMHMM analysis suggests that HVA 22 protein contains three transmembrane domains. SignalP showed no signal peptide and the phosphorylation sites viz. 30 serine, 8 threonine and 3 tyrosine residues were identified using Netphos server. The phylogenetic tree exhibited that HVA 22 from sugarcane variety Co 740 is closely associated with that of HVA 22 of Zea mays and Oryza sativa. qRT-PCR gene expression analysis showed that HVA 22 was differentially upregulated in drought tolerant and susceptible genotypes under water deficit stress conditions.