ANAC030 modulates leaf senescence by regulating JA biosynthesis, programmed cell death, and chlorophyll metabolism in Arabidopsis

Leaf senescence is a normal growth state exhibited in the final stage of plant growth and development, and its process is complex and is regulated by multiple exogenous and endogenous factors. However, the underlying regulatory mechanisms remain largely unknown. In this study, we found that Arabidopsis (Arabidopsis thaliana) ANAC030 is a novel regulator of leaf senescence. ANAC030 localizes in the nucleus to exert its function and binds to the canonical NACBS cis-element. Estradiol–inducible overexpression of ANAC030 accelerated the leaf senescence process, while dominant repression of ANAC030 delayed leaf senescence. Subsequently, molecular regulatory mechanisms were analyzed using techniques such as comparative RNA-sequencing, RT-qPCR, dual-luciferase reporter assay (dual-LUC), electrophoretic mobility shift assay (EMSA), and chromatin immunoprecipitation quantitative PCR (ChIP-qPCR). Accordingly, opposite changes of jasmomic acid (JA) were observed between ANAC030 overexpression and dominant repression plants. A genetic analysis of ANAC030 overexpression in the nye1 and lox2 mutant backgrounds indicated a direct regulatory relationship between ANAC030 and its target genes. The results demonstrated that ANAC030 can directly bind to the promoter regions of genes related to programmed cell death (PCD), chlorophyll metabolism, and JA synthesis, thereby promoting cell death and accelerating leaf senescence.·Taken together, this research reveals a crucial role of ANAC030 in regulating leaf senescence by integrating several related and distinct pathways.