通过挖掘水稻籽粒中锌含量显著关联的QTL,并结合基因功能注释、单倍型和灌浆期籽粒相对表达量分析,筛选与水稻籽粒锌含量相关的候选基因.本研究以139份西北早粳稻核心种质资源为试验材料,结合重测序获得的1800920个高可信度SNPs,基于一般线性模型(GLM,general linear mode l)进行全基因组关联分析,对显著QTL区间内候选基因进行功能注释,并对进一步筛选后的基因进行单倍型和籽粒灌浆期相对表达量分析,以期筛选出与籽粒锌含量相关的候选基因和优势单倍型.结果表明,139份水稻中籽粒锌含量存在丰富的表型变异,且符合正态分布.全基因组关联分析共关联到12个显著SNP,分布在第1、2、4、10、11号染色体上,结合候选区间内的基因功能注释,推测定位在囊泡中的OsFRDL2可能与水稻籽粒锌元素富集相关;单倍型和灌浆期籽粒相对表达量分析表明,OsFRDL2在优势单倍型Hap5中表达量相对较高.因此推测OsFRDL2可能与水稻籽粒锌元素富集相关.研究结果为解析水稻籽粒锌元素富集机制和开发富锌水稻分子标记提供理论基础,为培育富锌水稻提供基因资源.
Genome-wide Association Analysis and Candidate Genes Screening for Zn Content in Rice Seeds
By mining QTL significantly associated with zinc content in rice grains,combined with gene function annotation,haplotype and grain relative expression analysis at grain filling stage,candidate genes related to zinc content in rice grains were screened.In this study,139 core germplasm resources of early japonica rice in Northwest China were used as experimental materials.Combined with 1800920 high-confidence SNPs obtained by resequencing,genome-wide association analysis was performed based on the general linear model(GLM).The candidate genes in the significant QTL interval were functionally annotated,and the further screened genes were analyzed for haplotypes and relative expression levels at grain filling stage,in order to screen out candidate genes and dominant haplotypes related to grain zinc content.The results showed that there were abundant phenotypic variations in grain zinc content of 139 rice accessions,which were in accordance with normal distribution.Through genome-wide association analysis of zinc content in rice grains,a total of 12 significant SNPs were associated,which were distributed on chromosomes 1,2,4,10 and 11.Combined with the gene function annotation in the candidate interval,it was speculated that OsFRDL2 located in the vesicle may be related to the enrichment of zinc in rice grains.Through the analysis of haplotype and grain relative expression at filling stage,it was found that OsFRDL2 was relatively highly expressed in the dominant haplotype Hap5.Therefore,it is speculated that OsFRDL2 may be related to the enrichment of zinc in rice grains.The results provide a theoretical basis for analyzing the mechanism of zinc enrichment in rice grains and developing molecular markers of zinc-rich rice,and provide genetic resources for cultivating zinc-rich rice.
ricerice grainsZn contentgenome-wide association analysisgene candidate
NETL
NSTL
万方数据
