小麦烯醇化酶基因TaENO1-5B在多种环境下对株高与穗粒数的调控OA北大核心CSTPCD

[Objective]Enolase is a key rate-limiting enzyme in the process of glycolysis,and plays a crucial role in plant growth and development,and response to abiotic stress.The function of common wheat enolase gene TaENO1-5B was revealed and molecular markers were developed to provide genetic resources for improving wheat through molecular breeding.[Method]TaENO1-5B was cloned from wheat variety Hanxuan 10.The domains of its encoded protein were analyzed on the SMART website.The secondary and tertiary structures of the protein were predicted by Phyre2 software.Real-time quantitative fluorescent PCR was used to analyze the expression levels of the target gene in wheat tissues at different developmental stages and its expression patterns under phytohormone treatment and abiotic stress.Thirty wheat germplasm with rich genetic diversity were used as plant materials to analyze the gene sequence polymorphisms,and develop molecular markers.The association analysis between TaENO1-5B haplotypes and phenotypic traits was carried out in a natural population consisting of 323 wheat accessions.The trend of breeding selection of superior haplotype in different wheat production zones in China was analyzed by using a landrace population and a modern variety population.[Result]TaENO1-5B gene consists of 17 exons and 16 introns encoding 446 amino acids and contains a conserved N-terminal domain and a C-terminal TIM(triose-phosphate isomerase)barrel domain.TaENO1-5B was expressed in all tissues of wheat at seedling,jointing,heading and flowering stages,and the expression level was higher in roots,root bases and spikes.The TaENO1-5B promoter region contains a variety of cis-acting elements,including elements responding to plant hormones,such as abscisic acid(ABA),auxin(IAA),and methyl jasmonate(MeJA),as well as elements responding to drought and low temperature.The expression of TaENO1-5B was significantly induced by phytohormones and abiotic stress in wheat.Four SNPs were detected in the promoter region and three SNPs in the gene region of the TaENO1-5B gene,which constituted three haplotypes,i.e.,Hap-5B-1,Hap-5B-2,and Hap-5B-3.Among them,Hap-5B-2 was a favorable haplotype highly associated with shorter plant height,more spikelets per spike,and more grains per spike under various environments such as drought and high temperature,and had been positively selected in the breeding history of major wheat production zones in China.The KASP(kompetitive allele-specific PCR)marker developed based on the SNP(2 399 bp,G/A)of the TaENO1-5B promoter region was significantly correlated with the spikelet number per spike in multiple environments.[Conclusion]TaENO1-5B gene responds to phytohormones and abiotic stress,and is significantly correlated with plant height,spikelet number per spike and grain number per spike under various environments such as drought and high temperature.Hap-5B-2 is a favorable haplotype with shorter plant height and more number of spikelets and grains per spike.Molecular markers developed based on the variation sites of TaENO1-5B gene sequence can be used for genetic improvement of plant height and related yield traits in wheat.