Genome-Wide Identification and Expression Analysis of BrATGs and Their Different Roles in Response to Abiotic Stresses in Chinese Cabbage

Autophagy is an important degradation pathway that maintains cellular homeostasis in living organisms and plays a key role in plant fitness and immunity. To date, more than 30 autophagy-related genes (ATGs) have been identified in model plants such as Arabidopsis. However, autophagy in Chinese cabbage, the largest cultivated vegetable crop in China, has scarcely been studied. We identified 64 Chinese cabbage autophagy-associated genes, named BrATGs, at the genome-wide level. The majority of the BrATGs were highly conserved over a long evolutionary period, and the expression patterns indicated that BrATGs were most highly expressed in the healing tissues and flowers. Furthermore, BrATGs responded to the stresses of the heavy metal Cd, drought, salt, and low and high temperatures to varying degrees. Among them, BrATG8c/8j was specifically induced in response to drastic temperature changes; BrATG4c was upregulated only in response to drought and salt stress; and BrATG8f/10/VTI12C was highly expressed only in response to Cd stress. This work will advance the understanding of the molecular mechanisms underlying the abiotic stress response in Chinese cabbage.