Abstract
Sweet potato(Ipomoea batatas[L.]Lam.)is a crucial staple and bioenergy crop.Its abiotic stress tolerance holds significant importance in fully utilizing marginal lands.Transcriptional processes regulate abiotic stress responses,yet the molecular regulatory mechanisms in sweet potato remain unclear.In this study,a NAC(NAM,ATAF1/2,and CUC2)transcription factor,IbNAC087,was identified,which is commonly upregulated in salt-and drought-tolerant germ-plasms.Overexpression of IbNAC087 increased salt and drought tolerance by increasing jas-monic acid(JA)accumulation and activating re-active oxygen species(ROS)scavenging,whereas silencing this gene resulted in opposite phenotypes.JA-rich IbNAC087-OE(over-expression)plants exhibited more stomatal clo-sure 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 ac-tivates 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 ubiq-uitin ligase NAC087-INTERACTING E3 LIGASE(IbNIEL),negatively regulating salt and drought tolerance in sweet potato.IbNIEL ubiquitinated IbNAC087 to promote 26S proteasome degrada-tion,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.
基金项目
National Key R&D Program of China(2023YFD1200700/2023YFD1200702)
Beijing Natural Science Foundation(6212017)
Beijing Food Crops Innovation Consortium Program(BAIC02-2023)
Project of Sanya Yazhou Bay Science and Technology City(SCKJ-JYRC-2022-61/SYND-2022-09)
China Agriculture Research System of MOF and MARA(2023TC057/2022TC003)
NETL
NSTL
万方数据