IbNIEL-mediated degradation of IbNAC087 regulates jasmonic acid-dependent salt and drought tolerance in sweet potato

In this study, a NAC (NAM, ATAF1/2, and CUC2) transcription factor, IbNAC087, was identified, which is commonly upregulated in salt- and drought-tolerant germplasms. Overexpression of IbNAC087 increased salt and drought tolerance by increasing jasmonic acid (JA) accumulation and activating reactive oxygen species (ROS) scavenging, whereas silencing this gene resulted in opposite phenotypes. JA-rich IbNAC087-OE (overexpression) plants exhibited more stomatal closure than wild-type (WT) and IbNAC087-Ri plants under NaCl, polyethylene glycol, and methyl jasmonate treatments. IbNAC087 functions as a nuclear transcriptional activator and directly activates the expression of the key JA biosynthesis-related genes lipoxygenase (IbLOX) and allene oxide synthase (IbAOS). Moreover, IbNAC087 physically interacted with a RING-type E3 ubiquitin ligase NAC087-INTERACTING E3 LIGASE (IbNIEL), negatively regulating salt and drought tolerance in sweet potato. IbNIEL ubiquitinated IbNAC087 to promote 26S proteasome degradation, which weakened its activation on IbLOX and IbAOS. The findings provide insights into the mechanism underlying the IbNIEL-IbNAC087 module regulation of JA-dependent salt and drought response in sweet potato and provide candidate genes for improving abiotic stress tolerance in crops.PMID:38294064 | DOI:10.1111/jipb.13612

Source: Journal of Integrative Plant Biology - January 31, 2024 Category: Biology Authors: Xu Li Zhen Wang Sifan Sun Zhuoru Dai Jun Zhang Wenbin Wang Kui Peng Wenhao Geng Shuanghong Xia Qingchang Liu Hong Zhai Shaopei Gao Ning Zhao Feng Tian Huan Zhang Shaozhen He Source Type: research