Coumarate 3-hydroxylase(C3h)genes participate in the synthesis of lignin and may affect the properties of wood that are important for its commercial value.A better understanding of the natural variation in C3h genes a...Coumarate 3-hydroxylase(C3h)genes participate in the synthesis of lignin and may affect the properties of wood that are important for its commercial value.A better understanding of the natural variation in C3h genes and their associations to wood properties is required to effectively improve wood quality.We used a candidate gene-based association mapping approach to identify CfC3h allelic variants associated with traits that affect the wood properties of Catalpa fargesii.We first isolated the full-length CfC3h cDNA(1825 bp),which was expressed at relatively high levels in xylem according to real time-polymerase chain reaction.In totally,17 common single-nucleotide polymorphisms(minor allele frequency>5%)were identified through cloning and sequencing the CfC3h locus from a mapping population(including 88 unrelated natural C.fargesii individuals collected from main distribution area).Nucleotide diversity and linkage disequilibrium(LD)in CfC3h indicate that CfC3h has low nucleotide diversity(π_(t)=0.0031 andθ_(w)=0.0103)and relatively low LD(within 1800 bp;r^(2)≥0.1).An association analysis identified eight common single-nucleotide polymorphisms(SNPs)(false discovery rate,Q<0.10)and ten haplotypes(Q<0.10)associated with wood properties,explaining 4.92-12.09%of the phenotypic variance in an association population consisted of 125 unrelated natural individuals(The 88 individuals from the mapping population were comprised in the association population).Our study would provide new insight into C3h gene affecting wood quality,and the SNP markers identified would have potential applications in marker-assisted breeding in the future.展开更多
According to synthetic pathway of plant chlorogenic acid （CGA）, the expression patterns of genes encoding enzymes that are associated with CGA synthesis were studied in normally developed Xuehua pear fruit. The stud...According to synthetic pathway of plant chlorogenic acid （CGA）, the expression patterns of genes encoding enzymes that are associated with CGA synthesis were studied in normally developed Xuehua pear fruit. The study demonstrated that CGA content in peel and flesh of Xuehua pear decreased as fruit development progressed, with a higher level in peel. The expression levels of PbPAL 1, PbPAL2, PbC3H, PbC4H, Pb4CL 1, Pb4CL2, Pb4CL6, PbHC T1 and PbHC T3 genes decreased in fruit, which was consistent with the pattern of variation in CGA content. That indicated that these genes might be key genes for influencing fruit CGA synthesis in Xuehua pear. However, Pb4CL7 gene expression profile is not consistent with variation of CGA content, hence, it may not be a key gene involved in CGA synthesis.展开更多
基金This work was supported by the National Key Research and Development Program of China[No.2017YFD0600201]Forestry Industry Research Special Funds for Public Welfare Projects[No.201404101].
文摘Coumarate 3-hydroxylase(C3h)genes participate in the synthesis of lignin and may affect the properties of wood that are important for its commercial value.A better understanding of the natural variation in C3h genes and their associations to wood properties is required to effectively improve wood quality.We used a candidate gene-based association mapping approach to identify CfC3h allelic variants associated with traits that affect the wood properties of Catalpa fargesii.We first isolated the full-length CfC3h cDNA(1825 bp),which was expressed at relatively high levels in xylem according to real time-polymerase chain reaction.In totally,17 common single-nucleotide polymorphisms(minor allele frequency>5%)were identified through cloning and sequencing the CfC3h locus from a mapping population(including 88 unrelated natural C.fargesii individuals collected from main distribution area).Nucleotide diversity and linkage disequilibrium(LD)in CfC3h indicate that CfC3h has low nucleotide diversity(π_(t)=0.0031 andθ_(w)=0.0103)and relatively low LD(within 1800 bp;r^(2)≥0.1).An association analysis identified eight common single-nucleotide polymorphisms(SNPs)(false discovery rate,Q<0.10)and ten haplotypes(Q<0.10)associated with wood properties,explaining 4.92-12.09%of the phenotypic variance in an association population consisted of 125 unrelated natural individuals(The 88 individuals from the mapping population were comprised in the association population).Our study would provide new insight into C3h gene affecting wood quality,and the SNP markers identified would have potential applications in marker-assisted breeding in the future.
基金supported by the Specific Financial Funds of Hebei Province,China (494-0502-JSN-7FB3)
文摘According to synthetic pathway of plant chlorogenic acid （CGA）, the expression patterns of genes encoding enzymes that are associated with CGA synthesis were studied in normally developed Xuehua pear fruit. The study demonstrated that CGA content in peel and flesh of Xuehua pear decreased as fruit development progressed, with a higher level in peel. The expression levels of PbPAL 1, PbPAL2, PbC3H, PbC4H, Pb4CL 1, Pb4CL2, Pb4CL6, PbHC T1 and PbHC T3 genes decreased in fruit, which was consistent with the pattern of variation in CGA content. That indicated that these genes might be key genes for influencing fruit CGA synthesis in Xuehua pear. However, Pb4CL7 gene expression profile is not consistent with variation of CGA content, hence, it may not be a key gene involved in CGA synthesis.
