Abstract:

To investigate the expression profile of maize genes induced by submergence, a subtracted cDNA library of maize seedling roots was constructed using suppression subtractive hybridization (SSH). The cDNA of maize seedling roots treated with submergence (ST) was used as tester and what from untreated roots (UT) as driver. Products of the secondary PCR from the forward subtraction were cloned into T/A vector and transferred into Escherichia coli strain JM10B by electroporation. Four hundred and eight randomly chosen transformants carrying cDNA fragments were screened with PCR-Select Deferential Screening Kit. One hundred and eighty-four cDNA clones were identified as submergence specifically induced or highly expressed. After sequencing and removing redundant cDNAs, we got 95 submergence-induced cDNA clones. Of the 95 cDNA clones, 68 contain the regions with 60%-90% identity to their homolog in GenBank, 21 are expected to be novel genes, only 6 correspond to the published maize sequences. Key words: maize; expression profile; suppression subtractive hybridization (SSH); submergence

抑制差减杂交法分离玉米幼苗淹水诱导表达基因
高鹏 王国英 赵虎基 樊 立 陶亚忠
（中国农业大学农业生物技术国家重点实验室和国家玉米改良中心，北京100094

摘要： 以淹水处理 (submergence-treated ,ST)的玉米 (Zeamays L .)幼苗根部cDNA为目标群体 ,未处理 (untreated ,UT)的玉米幼苗根部cDNA为对照群体 ,进行抑制差减杂交。用经过UT差减的STcDNA构建了一个含有大约 2 0 0 0个独立克隆的差减文库。对随机挑取的 40 8个克隆进行差异筛选 ,获得了 1 84个在ST中特异表达或表达增强的候选克隆。对其中 1 55个cDNA克隆测序并去除重复克隆后 ,共得到 95个差异表达的cDNA片段。GenBank中BLAST查询结果表明 :6个克隆为已知的玉米核苷酸序列 ;6 8个克隆与已知基因或EST序列部分区域的同源性为 6 0 %～90 % ;2 1个克隆在GenBank中无法查到对应的同源序列 ,可能代表了新基因 ,或者由于序列位于变异丰富的 3′端而无法查到与其他物种基因的同源性。

关键词： 关键词： 玉米；诱导表达基因；抑制差减杂交；淹水胁迫
 

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