Molecular mapping and candidate gene analysis of the semi-dominant gene Vestigial glume1 in maize

摘要

cqvip:The glume is an organ of the maize spikelet and plays important roles in anther and kernel development.Vestigial glume1(Vg1)is a classic mutant associated with ligule and glume development.Here we report the phenotypic characterization,fine mapping,and candidate gene analysis of the Vg1 mutant.Vg1 is a semi-dominant and pleiotropic gene,and also affects plant height,ear height,and tassel length.Vg1 ligule degeneration begins at the first leaf,and the Vg1 tassel and ear can be distinguished from those of wild-type plants when their lengths reach respectively 55 mm and 51 mm.Using a BC3 mapping population of 11,445 plants,we delimited the Vg1 functional site to an interval of 7.4 kb,flanked by the markers InDelLM and CRM6.A putative cyclopropane fatty-acid synthase gene(ZmCPA-FAS1)was hypothesized to underlie the mutant phenotype.We detected a Helitron insertion in the sixth intron of ZmCPAFAS1.Its presence caused abnormal alternative splicing of ZmCPA-FAS1 that conferred new characteristics on the Vg1 mutant.These findings are a basis for further discovery of the molecularmechanism underlying glume development and a potential guide formaize breeding of small-glume varieties,especially sweet corn breeding.