In higher plants,the shoot apical meristem produces lateral organs in a regular spacing(phyllotaxy)and timing(plastochron).The molecular analysis of mutants associated with phyllotaxy and plastochron would increase ou...In higher plants,the shoot apical meristem produces lateral organs in a regular spacing(phyllotaxy)and timing(plastochron).The molecular analysis of mutants associated with phyllotaxy and plastochron would increase our understanding of the mechanism of shoot architecture formation.In this study,we identified mutant mnd8ynp5 that shows an increased rate of leaf emergence and a larger number of nodes in combination with a dwarfed growth habit from an EMS-treated population of the elite barley cultivar Yangnongpi 5.Using a map-based cloning strategy,the mnd8 gene was narrowed down to a 6.7-kb genomic interval on the long arm of chromosome 5H.Sequence analysis revealed that a C to T single-nucleotide mutation occurred at the first exon(position 953)of HORVU5Hr1G118820,leading to an alanine(Ala)to valine(Val)substitution at the 318th amino acid site.Next,HORVU5Hr1G118820 was defined as the candidate gene of MND8 encoding 514 amino acids and containing two multidrug and toxic compound extrusion(MATE)domains.It is highly homologous to maize Bige1and has a conserved function in the regulation of plant development by controlling the leaf initiation rate.Examination of modern barely varieties showed that Hap-1 was the dominant haplotype and was selected in barley breeding around the world.Collectively,our results indicated that mnd8ynp5 is a novel allele of the HORVU5Hr1G118820 gene that is possibly responsible for the shortened plastochron and many noded dwarf phenotype in barley.展开更多
基金funded by the Open Project Program of State Key Laboratory of Barley and Yak Germplasm Resources and Genetic Improvement,China(XZNKY2021-C-014-K01)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(19KJA560005)+1 种基金the China Agriculture Research System(CARS-05)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China。
文摘In higher plants,the shoot apical meristem produces lateral organs in a regular spacing(phyllotaxy)and timing(plastochron).The molecular analysis of mutants associated with phyllotaxy and plastochron would increase our understanding of the mechanism of shoot architecture formation.In this study,we identified mutant mnd8ynp5 that shows an increased rate of leaf emergence and a larger number of nodes in combination with a dwarfed growth habit from an EMS-treated population of the elite barley cultivar Yangnongpi 5.Using a map-based cloning strategy,the mnd8 gene was narrowed down to a 6.7-kb genomic interval on the long arm of chromosome 5H.Sequence analysis revealed that a C to T single-nucleotide mutation occurred at the first exon(position 953)of HORVU5Hr1G118820,leading to an alanine(Ala)to valine(Val)substitution at the 318th amino acid site.Next,HORVU5Hr1G118820 was defined as the candidate gene of MND8 encoding 514 amino acids and containing two multidrug and toxic compound extrusion(MATE)domains.It is highly homologous to maize Bige1and has a conserved function in the regulation of plant development by controlling the leaf initiation rate.Examination of modern barely varieties showed that Hap-1 was the dominant haplotype and was selected in barley breeding around the world.Collectively,our results indicated that mnd8ynp5 is a novel allele of the HORVU5Hr1G118820 gene that is possibly responsible for the shortened plastochron and many noded dwarf phenotype in barley.
