论文部分内容阅读
为探讨小麦杂种优势形成的分子机理，本研究选用普通小麦品种系3338、6554和2410TD及其强优势杂种Ⅰ（3338×6554）和弱优势杂种Ⅱ（2410TD×6554），利用mRNA差异显示方法分析了杂种和亲本幼苗叶片基因表达差异。结果表明：杂种与双亲间基因表达存在数量水平和质量水平的差异，但以量的差异为主。量的表达差异表现为：杂种基因表达增强或减弱，杂种基因表达偏向父本或母本；质的表达差异表现为单亲基因沉默，双亲基因沉默和单亲基因在杂种一代的表达，没有展示出杂种一代基因特异表达类型。杂种Ⅰ与双亲间基因的差异表这类型较杂种Ⅱ丰富，且发现许多杂种Ⅰ高水平表达的基因在杂种Ⅱ减弱表达或偏低亲表达。对经Northern杂交证实的XM1条带克隆后测序，并在Genbank中进行了同源序列比较，发现该差异表达cDNA片段为新序列。此外，对小麦mRNA差异显示中引物的选择及杂种和亲本基因表达差异与杂种优势的关系也进行了分析和讨论。
In order to explore the molecular mechanism of wheat heterosis, we selected three wheat lines 3338, 6554 and 2410TD and their dominant hybrids I (3338 × 6554) and weak heterosis Ⅱ (2410TD × 6554) Differences in gene expression between hybrid and parent seedling leaves. The results showed that there were differences in quantity and quality of gene expression between hybrids and parents, but the differences were mainly in quantity. The results showed that the expression of hybrid genes was enhanced or decreased, and the expression of hybrid genes was biased towards the male parent or female parent. The differences in the expression of quality between single parent gene silencing, parental gene silencing and single parent gene expression in hybrid generation did not show hybrid Generation specific gene expression types. The difference between the genes of hybrids I and their parents This type is more abundant than hybrids II and found that many of the genes expressed at high levels in hybrids I were weakened or under-expressed in hybrid II. The XM1 bands confirmed by Northern blot were cloned and sequenced. The homologous sequences were compared in Genbank, and the cDNA fragments were found to be new sequences. In addition, the selection of primers for differential display of wheat mRNA and the relationship between heterosis and heterosis were also analyzed and discussed.