Genome-wide Identification and Expression Analysis of the Auxin Receptor Gene Family in Chinese Cabbage

PurposeTo systematically analyze the auxin receptor BrTIR1/AFBs gene family in Chinese cabbage, to provide theoretical basis for the function mining and genetic improvement of BrTIR1/AFBs gene family in Chinese cabbage.

MethodUsing bioinformatics methods, analyzing the relationship between Chinese cabbage auxin receptor gene family evolution, coding protein, conservative domain structure and function components. Based on NCBI transcriptome sequencing (RNA-sep) data, analyze BrTIR1/AFBs gene families in Chinese cabbage expression patterns of different organizations, and under the condition of root disease invasion of expression.

ResultsTen BrTIR1/AFBs genes were identified from Chinese cabbage genome database. Multiple sequence alignment and phylogenetic tree analysis of the auxin receptor gene families of Arabidopsis thaliana, Brassica juncea and soybean showed that the BrTIR1/AFBs genes were divided into 6 subfamilies (TIR1, AFB1, AFB2, AFB3, AFB4 and AFB5), and the genes in the same subfamily had similar structures. Chromosomal localization results showed that the BrTIR1/AFBs gene family members were distributed on 7 chromosomes except Chr5, Chr6 and Chr10, showing an uneven distribution. Cis-acting element analysis showed that all members of the BrTIR1/AFBs gene family contained functional elements in response to auxin, defense, and stress, suggesting that these genes may be involved in relevant biological processes. Tissue expression pattern analysis revealed that the transcripts of 10 BrTIR1/AFBs genes were detected in 6 tissues, and the expression levels were significantly different in different tissues. The expression levels of BrTIR1/AFBs gene family in Chinese cabbage were significantly changed when the pathogen of clubroot was invaded.

ConclusionAuxin receptor BrTIR1/AFBs family of Chinese cabbage have conserved gene structure and functional domain, and play specific functions in different tissues of Chinese cabbage, and play an important role in resisting disease and drought.