Genome-Wide Analysis of ARGOS and Its Homologous Genes in Brassica Crops and Stress Tolerance Verification of the BnaC6.ARGOS in rapeseed

Abstract Rapeseed (Brassica napus) is the second largest oil crop in the world, which the yield and stress resistance of has always been the primary goal of researchers. Here, a rapeseed gene Auxin Regulated Gene involved in Organ Size (ARGOS; BnaC6.ARGOS) was isolated, and its overexpression could significantly increase the organ size in Arabidopsis. In the present study, 7, 5, and 19 putative ARGOS and their homologous genes were identified in Brassca rapa (B. rapa), Brassca oleracea (B. oleracea) and rapeseed, respectively. The results of subcellular localization experiments showed that the BnaC6.ARGOS expressed on the cell membrane. Different spatiotemporal expression patterns were displayed of BnaARGOS and homologous genes, and whose promoters were abundant in the light-, abscisic acid (ABA-), Methyl jasmonate (MeJA-) and drought stress cis-elements. In addition, BnaC6.ARGOS in rapeseed has been shown to be regulated by light, drought, and ABA concentration. In addition, overexpressing BnaC6.ARGOS significantly increases the germination rate of rapeseed seeds under drought stress compared to wild-type plants. The research results contributed to understanding the evolutionary relationship between ARGOS and its homologous genes in Brassica crops, and validate the biological function of BnaC6.ARGOS, making it a candidate gene for improving rapeseed yield and drought resistance.