OsELS6 regulates rice leaf senescence differently in vitro and in vivo via the jasmonic acid pathway

Abstract Leaf senescence is a crucial trait that significantly impacts crop quality and yield. However, whether plant leaf senescence genes are regulated by the same mechanisms in vitro and in vivo has not been determined. Here, we screened a rice (Oryza sativa) leaf senescence mutant exhibiting a delayed leaf senescence phenotype in vitro and an early leaf senescence phenotype in vivo. Map-based cloning revealed that these phenotypes were caused by OsELS6, which encodes ABERRANT LATERAL ROOT FORMATION4 (ALF4), a protein that inhibits SKP1-CUL1-F box protein (SCF) E3 ligase activity. In addition, OsELS6 interacted with the U-box E3 ligase OsHUB1, which may be involved in seed development, and with OsCDC48, which is involved in leaf senescence. Integrated transcriptomic, proteomic, and ubiquitomic analyses, as well as exogenous application of jasmonic acid (JA), demonstrated that OsELS6 is related to OsCDC48 and plays opposite roles in rice leaf senescence in vitro and in vivo via the JA pathway. This study elucidated the regulatory mechanisms of OsELS6 in rice leaf senescence in vitro and in vivo, revealing that JA plays a key role in the regulation of leaf senescence by OsELS6 and OsCDC48.