Molecular Characterization and Stress Induced Expression Analysis of LIM Gene Family of Brassica rapa

LIM (Lin-11, Isl-1 and Mec-3 domains) genes have been reported so far to trigger the formation of actin bundles, a major higher-order cytoskeletal assembly, in higher plants but, still now stress resistance related functions of these genes are not well known. Brassica is a very important vegetable group worldwide and abiotic stresses are major concern for these crops. To address this concern, enhancement of resistance against stresses exploiting stress resistance related genes, offers the most efficient approach. In this study, we collected 22 LIM genes designated as Brassica rapa LIM (BrLIM) from the Brassica database and confirmed as LIM genes by sequences analysis and found a high degree of homology with other published LIM genes. In the expression analysis, an organ specific expression of these genes was observed in chinese cabbage plants. BrLIM1, 2, 3, 12, 13, 19, 20, 21 and 22 expressed only in flower buds and their expression was high in early flowering stages except BrLIM19. These genes also showed clear grouping according to organ specific expression in the phylogenetic analysis. In addition, two BrLIMs responded to Fusarium oxysporum f. sp. conglutinans infection while, nine, ten, six, seven and eight BrLIMs responded to salt, ABA, pH5, pH7 and pH9 stress treatments in chinese cabbage plants, respectively. All these data revealed that these BrLIM genes may be involved in resistance against biotic and abiotic stresses for Brassica.