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.

植物扩展蛋白基因是细胞壁松散蛋白，通过修饰邻近的细胞壁与纤维细胞发育相关。据我们所知，没有对含韧皮纤维作物中的扩展蛋白基因进行全基因组综合分析。因此，在这项研究中，我们在黄麻纤维发育过程中进行了扩展蛋白的全基因组分子表征、分类、理化特性、进化关系和表达谱。在黄麻（Corchorus olitorius ）中鉴定出 26 个扩展蛋白基因) 基因组并分为四个亚家族：20 个 CoEXPA、2 个 CoEXPB、1 个 CoEXLA 和 3 个 CoEXLB。相同亚家族中的大多数 CoEXP 表现出相似的基因结构和基序组成。表达分析显示20个CoEXPs在黄麻茎的不同区域表达。五种 CoEXPAs 主要在树皮组织中表达，表明它们与纤维生物合成有关。相比之下，三种 CoEXPA 和一种 CoEXLB 优先在木质棒组织中表达，表明它们参与了黄麻的棒发育。黄麻扩展蛋白的综合分析可为黄麻的进一步功能表征和遗传操作以提高纤维质量提供坚实的基础。