为解决条斑紫菜(Neopyropia yezoensis)遗传育种研究中缺乏生长性状遗传位点的问题,本研究针对条斑紫菜配子体的4个重要生长性状展开了全基因组关联分析(Genome-wide association study,GWAS)。首先,在相同环境下纯化培养了130个单一基...为解决条斑紫菜(Neopyropia yezoensis)遗传育种研究中缺乏生长性状遗传位点的问题,本研究针对条斑紫菜配子体的4个重要生长性状展开了全基因组关联分析(Genome-wide association study,GWAS)。首先,在相同环境下纯化培养了130个单一基因型条斑紫菜个体,并测量了叶长、叶宽、鲜质量和干质量这4个与生长相关的表型数据,进而分析并发现条斑紫菜不同生长性状的变异系数(Coefficient of variation)为32.63%~50.95%,各性状之间存在显著的相关性。利用全基因组重测序技术获得每个个体的基因型。对重测序数据质检后,共得到405999个高质量的单核苷酸多态性(Single nucleotide polymorphism,SNP)位点,其中53077个位点位于外显子区域,SNPs位点转换与颠换的数量之比为1.23。群体结构分析发现,研究群体可以分为4个亚群,不同亚群之间存在明显的遗传差异,而分群情况并非严格按照地理位置划分。测序个体之间的亲缘关系较远,连锁不平衡(Linkage disequilibrium,LD)衰减距离较小,这表明样本的遗传变异比较丰富。本研究利用混合线性模型(Q+K)进行了性状关联位点的筛选,共筛选出90个显著关联位点,其中67个位点与叶长显著相关,17个位点与叶宽显著相关,4个位点与鲜质量显著相关,2个位点与干质量显著相关,这些位点能够解释16.12%~24.85%的表型变异。在显著性位点上、下游20 kb范围内筛选,得到39个可能与生长性状相关的候选基因,基因功能涉及细胞增殖、控制细胞代谢途径以及调控植物的生长发育等。本文为条斑紫菜分子育种研究的开展提供了候选遗传位点和重要依据。展开更多
The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yi...The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yields,which have been documented at commercial mussel farms in the United Kingdom,the United States of America,Canada,Spain,New Zealand and China.Byssus is an important attachment structure for marine mussels,and weakness in byssal thread attachment is a major factor leading to mussel detachment from ropes.To investigate the relationship between genetic variability and byssal thread phenotypic characteristics in the hard-shelled mussel(Mytilus coruscus),we collected three wild populations of M.coruscus from different latitudes in the East China Sea,including the Shengsi(SS),Jiaojiang(JJ),and Fuding(FD)populations.The genetic diversity and structure of these populations were investigated using 10 microsatellite loci.The mean observed heterozygosity(Ho)in the SS population was 0.44,higher than the mean Ho values of the JJ(0.40)and FD(0.39)populations.The mean inbreeding coefficients(F_(is))in the SS population was 0.20,lower than the mean F_(is)values of the JJ(0.33)and FD populations(0.40).These results revealed that the SS population exhibited higher genetic diversity compared to the other two populations.The different numbers of private alleles(P_(a))in the three populations,ranging from 10 to 17,suggest that these populations have experienced selective pressures from various environments.Moreover,genetic differentiation was observed in the genetic distance between the SS population and the other two populations.We also examined the phenotypic characteristics of their byssal threads.There were significant differences in byssus attachment strength among the three populations,with the SS population located at the highest latitude secreting more byssal threads and exhibiting greater byssal breaking force and plaque adhesion strength,while the Fuding(FD)population located at the lowest latitude had the weakest byssal attachment.The observed differentiation in private alleles and byssus phenotypes might suggest that the three wild populations have experienced different environmental selective pressures.This study provides insight for future genetic enhancement programs aimed at improving byssus attachment in M.coruscus.展开更多
文摘为解决条斑紫菜(Neopyropia yezoensis)遗传育种研究中缺乏生长性状遗传位点的问题,本研究针对条斑紫菜配子体的4个重要生长性状展开了全基因组关联分析(Genome-wide association study,GWAS)。首先,在相同环境下纯化培养了130个单一基因型条斑紫菜个体,并测量了叶长、叶宽、鲜质量和干质量这4个与生长相关的表型数据,进而分析并发现条斑紫菜不同生长性状的变异系数(Coefficient of variation)为32.63%~50.95%,各性状之间存在显著的相关性。利用全基因组重测序技术获得每个个体的基因型。对重测序数据质检后,共得到405999个高质量的单核苷酸多态性(Single nucleotide polymorphism,SNP)位点,其中53077个位点位于外显子区域,SNPs位点转换与颠换的数量之比为1.23。群体结构分析发现,研究群体可以分为4个亚群,不同亚群之间存在明显的遗传差异,而分群情况并非严格按照地理位置划分。测序个体之间的亲缘关系较远,连锁不平衡(Linkage disequilibrium,LD)衰减距离较小,这表明样本的遗传变异比较丰富。本研究利用混合线性模型(Q+K)进行了性状关联位点的筛选,共筛选出90个显著关联位点,其中67个位点与叶长显著相关,17个位点与叶宽显著相关,4个位点与鲜质量显著相关,2个位点与干质量显著相关,这些位点能够解释16.12%~24.85%的表型变异。在显著性位点上、下游20 kb范围内筛选,得到39个可能与生长性状相关的候选基因,基因功能涉及细胞增殖、控制细胞代谢途径以及调控植物的生长发育等。本文为条斑紫菜分子育种研究的开展提供了候选遗传位点和重要依据。
文摘The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yields,which have been documented at commercial mussel farms in the United Kingdom,the United States of America,Canada,Spain,New Zealand and China.Byssus is an important attachment structure for marine mussels,and weakness in byssal thread attachment is a major factor leading to mussel detachment from ropes.To investigate the relationship between genetic variability and byssal thread phenotypic characteristics in the hard-shelled mussel(Mytilus coruscus),we collected three wild populations of M.coruscus from different latitudes in the East China Sea,including the Shengsi(SS),Jiaojiang(JJ),and Fuding(FD)populations.The genetic diversity and structure of these populations were investigated using 10 microsatellite loci.The mean observed heterozygosity(Ho)in the SS population was 0.44,higher than the mean Ho values of the JJ(0.40)and FD(0.39)populations.The mean inbreeding coefficients(F_(is))in the SS population was 0.20,lower than the mean F_(is)values of the JJ(0.33)and FD populations(0.40).These results revealed that the SS population exhibited higher genetic diversity compared to the other two populations.The different numbers of private alleles(P_(a))in the three populations,ranging from 10 to 17,suggest that these populations have experienced selective pressures from various environments.Moreover,genetic differentiation was observed in the genetic distance between the SS population and the other two populations.We also examined the phenotypic characteristics of their byssal threads.There were significant differences in byssus attachment strength among the three populations,with the SS population located at the highest latitude secreting more byssal threads and exhibiting greater byssal breaking force and plaque adhesion strength,while the Fuding(FD)population located at the lowest latitude had the weakest byssal attachment.The observed differentiation in private alleles and byssus phenotypes might suggest that the three wild populations have experienced different environmental selective pressures.This study provides insight for future genetic enhancement programs aimed at improving byssus attachment in M.coruscus.
