甘薯HXK基因的克隆、组织表达及生物信息分析

Cloning,organ-specific expression pattern and sequence analysis of HXK gene in Sweet potato

通过RT-PCR技术从甘薯的总RNA中克隆得到了全长的己糖激酶基因,测序结果表明HXK(hexokinase)基因编码区长1491bp,编码496个氨基酸,其翻译的蛋白质分子量为53.4kD,其氨基酸序列与其它已知高等植物HXK基因具有很高的同源性.构建了原核表达载体pET-HXK,经IPTG诱导后可表达获得相对分子量约为71kD的外源融合蛋白,与预测结果一致.并对HXK基因在不同组织中的转录水平进行了数字表达谱和荧光定量分析.

The HXK gene in sweet potato contains an open reading frame （ORF）of 1,491 bp encoding a peptide of 496 amino acids with a molecular mass of 53.4 kD.The amino acid sequence of IbHXK has high homology with HXK genes from other plants.The IbHXK gene was also inserted into the pET32a （＋）vector,and the recombinant plasmid pET-HXK was then transformated into E.coli BL2 1 （DE3 ） for prokaryotic expression induced by different concentrations of IPTG.The transcript levels of the HXK gene in different tissues were invistigated by the digital gene expression profiling （DGE）and quantitative RT-PCR analysis.