玉米苹果酸脱氢酶基因的分离与结构分析

以一个玉米（ＺｅａｍａｙｓＬ．）杂种一代超亲表达的ｃＤＮＡ片段为探针，从玉米幼苗期ｃＤＮＡ文库中筛选到一个全长１２８７ｂｐ的ｃＤＮＡ克隆。序列分析表明，该ｃＤＮＡ编码细胞质苹果酸脱氢酶，推导的氨基酸序列与龙须海棠（Ｍｅｓｅｍｂｒｙａｎｔｈｅｍｕｍ　ｃｒｙｓｔａｌｌｉｕｍ　Ｌ．）及拟南芥（Ａｒａｂｉｄｏｐｓｉｓ　ｔｈａｌｉａｎａ（Ｌ．）Ｈｅｙｎｈ．）同一编码基因的氨基酸序列同源性分别为９０％和８４％。这是禾谷类作物中首次克隆的编码细胞质苹果酸脱氢酶的完整基因。

Isolation and Characterization of a cDNA Encoding Maize Cytosolic Malate Dehydrogenase

A cDNA fragment derived from a gene over-expressing in hybrid maize (Zea mays L. ) was isolated with RT-PCR and used as probe to screen cDNA library of hybrid maize seedlings. A positive cDNA clone ZHO2 corresponding to the full-length mRNA sequence was obtained, which was shown to have an open reading fare encoding 332 a. a. DNA and proteinase database seareh revealed that the deduced amino acid sequence of ZHO2 has high similarity with the cMDH of Mesembryanthemum crystallium L. and Arabidopsis thaliana (L. ) Heynh. up to 90% and 84%, respectively. This is the first report of the full-length gene coding for the cereal cMDH.