小麦拔节过程中基部茎节的基因差异表达

Differential Gene Expression in the Basal Stems of Wheat at the Jointing Stage

采用差异显示逆转录PCR(DD-RT-PCR)技术分析小麦基部茎节伸长过程中基因表达差异的结果表明,小麦拔节前和拔节后基部茎节中存在明显的基因表达差异(包括质和量的差异)。从具有质的差异表达基因中挑选了4个基因进行cDNA片段(编号为WSR1～4)的克隆、测序和GenBank数据库序列同源性比对分析,结果显示,WSR1与大麦中编码Ser/Thr蛋白激酶的序列具有很高的同源性,WSR2的功能未知,WSR3高度同源于玉米中编码Ty3/gypsy类反转座子反转录酶的序列,WSR4高度同源于小麦的端粒关联DNA。半定量RT-PCR技术分析拔节过程中克隆基因WSR1～4表达特性显示,除了WSR4以外,其余3个基因的表达模式和通过DD-RT-PCR分析所展示的差异表达趋势基本一致。

In order to study the molecular mechanism of wheat stem elongation, the differential display reverse transcription PCR （DD-RT-PCR） was used to identify the gene expression pattern during the basal stem elongation in wheat plant. The results showed that obvious differential gene expression was observed during the stern elongation, including qualitative and quantitative differences. From those qualitatively differentially expressed genes, four of them, designated as WSR1-4, were selected for cDNA fragment cloning and sequencing. Sequence homology search in GenBank database showed that the WSR1 was highly similar to a barley sequence encoding the serine/threonine protein kinase, WSR2 had no homology hits, WSR3 showed high similarity to a maize sequence encoding the Ty3/gypsy-type retrotransposon reverse transcriptase, while WSR4 showed high similarity to wheat telomere-associated DNA. The expression patterns of these four cDNAs were analyzed via semi-quantitative RT-PCR in the elongating wheat stem, the results showed that the expression patterns of three cloned cDNAs, except the WSR4, were basically agree with the expression trends displayed in DD-RT-PCR analysis.