Genome-Wide Identification of the Kinesin Gene Family in Soybean and Its Response to Salt Stress

The kinesin (KIN) gene family is a subgroup of motor proteins. It plays a critical role in plant development and responses to environmental stresses. However, their function in soybean salt tolerance has yet to be clearly defined. This study employed bioinformatics approaches and identified 139 kinesin family members in the soybean genome. These 139 genes were classified into 10 subgroups, unevenly distributed across the chromosomes. The promoter regions of GmKIN genes harbored several stress-responsive elements, and segmental duplication was the primary driver of the expansion of the GmKIN gene family. Based on publicly available RNA-seq data, we studied the response patterns of 139 GmKIN genes to salt stress and found that 20 KIN genes in soybeans were upregulated after salt stress, with GmKIN114, GmKIN102, GmKIN109, and GmKIN99 showing more than a threefold increase in their expression under salt stress. Using quantitative fluorescence PCR, transgenic yeast, and a transgenic hairy root system, we preliminarily validated the salt tolerance functions of the four KIN genes in soybeans. This study probed into the GmKIN gene family in soybean, offering valuable insights into the functional roles of these genes in stress adaptation.