The discovery of a wild abortive-type(WA)cytoplasmic male sterile(CMS)line and breeding its restorer line have led to the commercialization of three-line hybrid rice,contributing considerably to global food security.H...The discovery of a wild abortive-type(WA)cytoplasmic male sterile(CMS)line and breeding its restorer line have led to the commercialization of three-line hybrid rice,contributing considerably to global food security.However,the molecular mechanisms underlyingfertility abortion and the restoration of CMs-WA lines remain largely elusive.In this study,we cloned a restorer gene,Rf2o,following a genome-wide association study analysis of the core parent lines of three-line hybrid rice.We found that Rf20 was present in all core parental lines,but different haplotypes and structural variants of its gene resulted in differences in Rf2o expression levels between sterileand restored lines.Rf20 could restorepollen fertility in the CMS-WA line and was found to be responsible for fertility restoration in some CMs lines under high temperatures.In addition,we found that Rf20 encodes a pentatricopeptide repeat protein that competes with WA352 for binding with COX11.This interaction enhances Cox11's function as a scavenger of reactive oxygen species,which in turn restores pollenfertility.Collectively,ourstudysuggestsanewactionmodeforpentatricopeptide repeatproteins inthe fertilityrestorationofCMs lines,providing an essential theoretical basisforbreedingrobustrestorer lines and for overcoming high temperature-induced fertility recovery of some CMS lines.展开更多
基金Biological Breeding-Major Projects(2023ZD04076)National Key Research and Development Project(2022YFD1200800)+1 种基金Hunan Natural Science Foundation(2023JJ30442)Special Funds for the Construction of Innovative Provinces in Hunan Province(2021NK1002).
文摘The discovery of a wild abortive-type(WA)cytoplasmic male sterile(CMS)line and breeding its restorer line have led to the commercialization of three-line hybrid rice,contributing considerably to global food security.However,the molecular mechanisms underlyingfertility abortion and the restoration of CMs-WA lines remain largely elusive.In this study,we cloned a restorer gene,Rf2o,following a genome-wide association study analysis of the core parent lines of three-line hybrid rice.We found that Rf20 was present in all core parental lines,but different haplotypes and structural variants of its gene resulted in differences in Rf2o expression levels between sterileand restored lines.Rf20 could restorepollen fertility in the CMS-WA line and was found to be responsible for fertility restoration in some CMs lines under high temperatures.In addition,we found that Rf20 encodes a pentatricopeptide repeat protein that competes with WA352 for binding with COX11.This interaction enhances Cox11's function as a scavenger of reactive oxygen species,which in turn restores pollenfertility.Collectively,ourstudysuggestsanewactionmodeforpentatricopeptide repeatproteins inthe fertilityrestorationofCMs lines,providing an essential theoretical basisforbreedingrobustrestorer lines and for overcoming high temperature-induced fertility recovery of some CMS lines.
