Phosphorylation status of CPK28 affects its ubiquitination and protein stability----中国科学院遗传发育所农业资源研究中心

科研成果

论文

论文题目	Phosphorylation status of CPK28 affects its ubiquitination and protein stability
作　　者	刘晓彤；周园园；陈可欣；肖泽军；梁雪莲；吕东平;
发表年度	2023
刊物名称	NEW PHYTOLOGIST
卷、期、页码	237; 4; 1270-1284
影响因子
论文摘要	center dot Plant innate immunity is tightly regulated. The Arabidopsis thaliana CALCIUM-DEPENDENT PROTEIN KINASE28 (CPK28) functions as a negative immune regulator. We recently demonstrate that CPK28 undergoes ubiquitination that is mediated by two ubiquitin ligases, ARABIDOPSIS TOXICOS EN LEVADURA31 (ATL31) and ATL6, which results in its proteasomal degradation. CPK28 undergoes both intermolecular autophosphorylation and BIK1-mediated phosphorylation. However, whether the phosphorylation status of CPK28 dictates its ubiquitination and degradation is unknown yet.center dot We used immune response analysis, transient degradation system, ubiquitination assays, co-immunoprecipitation, and other biochemical and genetic approaches to investigate the effect of the phosphorylation status of CPK28 on its degradation mediated by ATL31/6.center dot We found the mutation of Ser318 (a site of both intermolecular autophosphorylation and BIK1-mediated phosphorylation) or a BIK1 phosphorylation site on CPK28 leads to its compromised association with ATL31 and reduced ubiquitination by ATL31. Moreover, we confirm the previous findings that two CPK28s can interact with each other, which likely promotes the intermolecular autophosphorylation. We also show that the phosphorylation status of CPK28 in turn affects its intermolecular association.center dot We demonstrate that the phosphorylation status of CPK28 affects its degradation mediated by ATL31. Our findings reveal a link between phosphorylation of CPK28 and its ubiquitination and degradation.
全文链接	http://dx.doi.org/10.1111/nph.18596
附件地址