玉米抽穗期亲本及其杂交种间基因差异表达与杂种优势的关系

Differential Gene Expression Between Hybrids and Their Parental Inbreds are Correlated with Heterosis in Heading Stage Functional Leaves of Maize

为探讨玉米杂种优势形成的分子机理,选用了8个玉米自交系和它们的5个杂交种,采用mRNA差异显示技术分析了杂种和亲本之间抽穗期叶片的基因表达差异模式。结果表明:所选用的杂交种与自交系之间的基因表达模式可以分为5种类型:杂种特异表达型(W1)、单亲显性表达型(W2)、双亲表达沉默型(W3)、单亲沉默表达型(W4)、亲本和杂交种表达一致型(W5),所占比例分别为2.81%,16.92%,11.79%,4.25%和64.23%。还对每种差异表达模式与12个杂种性状表现和中亲优势进行了相关分析。

To explore the genetic mechanism of heterosis, 8 maize inbreds line and their 5 hybrids were employed and analyzed the patterns of differential gene expression in functional leaves at heading stage. The results revealed that the differential expression patterns between inbreds and their hybrids are as following： bands observed only in hybrids （W1）, bands only present in one parent （W2）, bands present in one parent and Fz but absent in the other parent （W3 ）, bands present in both parents but absent in F1 （W4）, bands present in both parents and F1（W5）, which accounted for 2.81%, 16.92 %, 11.79 %, 4.25 % and 64.23 %, respectively. The correlations between differential gene expression pat- terns and the mid-parent heterosis of twelve agronomic traits were estimated.