Definition and regulatory analysis of the SUMOylation system in Caixin (Brassica rapa var. Parachinensis) during pectobacterium carotovorum infection

The modification of protein substrates by small ubiquitin-related modifier (SUMO) plays a vital role in plants subjected to biotic and abiotic stresses. However, its role in the stress responses of Brassica plants remains poorly understood.

A genome-wide analysis revealed the presence of 30 SUMOylation genes in the Caixin genome. These results demonstrated that the Caixin genome contains all the necessary components for SUMOylation. Analysis of the cis-acting elements revealed that the promoters of SUMOylation genes presented diverse combinations of developmental and stress-related cis-regulatory elements. The RNA-seq data indicated that 23 SUMOylation genes presented relatively high expression levels under normal conditions and exhibited a notable decrease in expression following Pectobacterium carotovorum subsp. carotovorum (Pcc) infection. Additionally, dynamic alterations in SUMO conjugates were observed in response to Pcc infection.

The Caixin genome contains genes involved in SUMOylation. The majority of these genes presented multiple copies, and analyses of their transcription and protein profiles indicate that they may play a role in the response to Pcc infection.