Genome-wide Identification and Characterization of Expansin Genes in Jute

Plant expansin genes are cell wall loosening proteins that are associated in fibre cell development by modifying neighboring cell wall. To the best of our knowledge, there is no genome-wide comprehensive analysis of expansin genes in bast fibre bearing crops. Therefore, in this study, we performed genome-wide molecular characterization, classification, physico-chemical properties, evolutionary relationship and expression profiling of expansins during jute fibre development. Twenty-six expansin genes identified in jute (Corchorus olitorius) genome and divided into four subfamilies: 20 CoEXPA, 2 CoEXPB, 1 CoEXLA and 3 CoEXLB. Most of the CoEXPs in same subfamilies exhibited similar gene structures and motif compositions. Expression analysis revealed that 20 CoEXPs were expressed in the different regions of jute stem. Five CoEXPAs has predominantly expressed in bark tissues suggesting their association in fibre biosynthesis. In contrast, three CoEXPAs and one CoEXLB were preferentially expressed in woody stick tissues suggesting their involvement in stick development of jute. The comprehensive analysis of jute expansins can serve as solid foundation for further functional characterization and genetic manipulation of jute to improve fibre quality.