positively regulates the infection of Chinese cabbage by .

Introduction: Chinese cabbage is one of the most important vegetable crops in China. However, the clubroot disease caused by the infection of has seriously affected the yield and quality of Chinese cabbage. In our previous study, gene was found to be significantly up-regulated in diseased roots of Chinese cabbage after inoculation with have the properties of substrate recognition during ubiquitin-mediated proteolysis. A variety of plant can activate immunity response through the ubiquitination pathway. Therefore, it is very important to study the function of in response to .

Methods: In this study, The expression pattern of Gene was measured by qRT-PCR and Hybridization (ISH). The expression location of in cells was determined by subcellular localization. The function of was verified by Virus-induced Gene Silencing (VIGS). proteins interacting with BrUFO protein were screened by yeast two-hybrid.

Results: Quantitative real-time polymerase chain reactions (qRT-PCR) and in situ hybridization analysis showed that expression of gene in the resistant plants was lower than that in susceptible plants. Subcellular localization analysis showed that gene was expressed in the nucleus. Virus-induced gene silencing (VIGS) analysis showed that silencing of gene reduced the incidence of clubroot disease. Six proteins interacting with BrUFO protein were screened by YH assay. Two of them (Bra038955, a B-cell receptor-associated 31-like protein and Bra021273, a GDSL-motif esterase/acyltransferase/lipase Enzyme) were confirmed to strongly interact with BrUFO protein.

Discussion: gene should be a key gene of chinese cabbage against the infection of gene silencing improves the resistance of plants to clubroot disease. BrUFO protein may interact with CUS2 to induce ubiquitination in PRR-mediated PTI reaction through GDSL lipases, so as to achieve the effect of Chinese cabbage against the infection of