Heterosis for biomass-related traits in Arabidopsis investigated by quantitative trait loci analysis of the triple testcross design with recombinant inbred lines
Heterosis for biomass-related traits in Arabidopsis investigated by quantitative trait loci analysis of the triple testcross design with recombinant inbred lines
复制标题
DOI：
10.1534/genetics.107.077628
复制
发表时间：
2007-11-01
期刊：
影响因子：
3.3
通讯作者：
Melchinger, Albrecht E.
中科院分区：
文献类型：
--
作者：
Kusterer, Barbara;Piepho, Hans-Peter;Melchinger, Albrecht E.
拟南芥已成为植物遗传学和功能基因组学研究的主要模式物种，包括杂种优势遗传原因的研究。我们应用三重测交（TTC）设计和一种新的生物统计学方法，通过（i）估计杂种优势QTL的数量，基因组位置和遗传效应，（ii）表征其基因作用模式，（iii）通过全基因组扫描和标记x标记相互作用检测上位性效应的存在，来鉴定和表征5个生物量相关性状杂种优势的数量性状位点（QTL）。总共有234个重组自交系（RILs）的拟南芥杂种C24 × Col-0的父母线和他们的F，并与110单核苷酸多态性（SNP）市场进行了分析。QTL分析使用线性转换Z（1）、Z（2）和Z（3）进行，所述线性转换Z（1）、Z（2）和Z（3）从TTC后代的校正的进入平均值计算。与Z1，我们检测到12个QTL显示增强加性效应。利用762，我们定位了6个用于增强显性效应的QTL。一维基因组扫描与Z（3）揭示了两个基因组区域显着负显性x加性上位效应。标记对之间的方差的双向分析揭示了9个双基因上位性相互作用：6个反映显性X显性效应与变量符号和3个反映加性X加性效应与正号。我们的结论是，拟南芥生物量相关性状的杂种优势具有多基因的基础，超显性和/或上位性可能是基因作用的主要类型。
Arabidopsis thaliana has emerged as a leading model species in plant genetics and functional genomics including research on the genetic causes of heterosis. We applied a triple testcross (TTC) design and a novel biometrical approach to identify and characterize quantitative trait loci (QTL) for heterosis of five biomass-related traits by (i) estimating the number, genomic positions, and genetic effects of heterotic QTL, (ii) characterizing their mode of gene action, and (iii) testing for presence of epistatic effects by a genomewide scan and marker x marker interactions. In total, 234 recombinant inbred lines (RILs) of Arabidopsis hybrid C24 x Col-0 were crossed to both parental lines and their F, and analyzed with 110 ;single-nucleotide polymorphism (SNP) markets. QTL analyses were conducted using linear transformations Z(1), Z(2), and Z(3) calculated from the adjusted entry means of TTC progenies. With Z1, we detected 12 QTL displaying augmented additive effects. With 762, we mapped six QTL for augmented dominance effects. A one-dimensional genome scan with Z(3) revealed two genomic regions with significantly negative dominance x additive epistatic effects. Two-way analyses of variance between marker pairs revealed nine digenic epistatic interactions: six reflecting dominance x dominance effects with variable sign and three reflecting additive x additive effects with positive sign. We conclude that heterosis for biomass-related traits in Arabidopsis has a polygenic basis with overdominance and/or epistasis being presumably the main types of gene action.