水稻蛋白激酶基因Pti1的克隆与分析

植物Pti1基因编码丝氨酸/苏氨酸蛋白激酶,是重要的抗病相关基因。在水稻抗褐飞虱基因Qbp1所在的染色体区段存在一个与番茄Pti1基因高度同源的序列片段。从抗虫水稻B5中分离了Pti1基因的全长cDNA克隆,测定了基因组序列。分析发现,水稻中Pti1基因长度有5644bp,含有7个内含子,编码368个氨基酸的激酶蛋白。其蛋白质的C末端在不同植物之间具有高度的保守性,而N末端的变异则相对较大。对不同水稻材料Pti1基因的序列进行了比较,发现药用野生稻与栽培稻之间存在较大的差异,而栽培稻各品种之间的差异较小。讨论了Pti1基因在抗虫防卫反应中可能的作用。

Cloning and Analysis of the Protein Kinase-encoding Gene Pti1 in Rice

Pti1 gene in plant is an important disease-resistance-related gene,encoding for a ser/thr protein kinase.In the genomic region of rice where the brown planthopper resistant gene Qbp1 lies,there is a gene with high homology to the Pti1 gene in tomato.We isolated the full-length cDNA of Pti1 gene from insect-resistant rice B5 and the corresponding genomic fragment.The Pti1 gene in rice is 5644 bp long,containing 7 introns and coding for a protein kinase of 368 aa.The C end of its protein is highly conservative and N end is relatively variable.The genomic fragments of this gene in several rice species including Oryza officinalis Wall ex Watt were sequenced and compared, revealing great difference between wild rice and cultivated rice;but the difference among cultivated rice species is faint.The possible role Pti1 gene may play in rice resistance against brown planthopper was discussed.