中文摘要：

电子克隆是随着EST计划和生物信息学发展起来的基因克隆策略。运用电子克隆的方法获得甘蔗S-APX2基因。以水稻中一个基因OsAPX2为种子序列,对甘蔗的EST数据库进行搜索,应用相关软件进行预测和分析。获得一个甘蔗APX基因S-APX2的cDNA序列全长,该序列长1110bp,包含一个完整的975bp的ORF,编码324个氨基酸;属于疏水性蛋白,编码蛋白含有Heme binding site,Substrate binding site,K＋binding site,Ascorbate-peroxidase结合位点和保守域,属于Plant-peroxidase-like Superfamily家族;亚细胞定位分析显示,编码蛋白位于植物细胞的线粒体中。具有5个丝氨酸磷酸化位点,9个苏氨酸磷酸化位点以及1个酪氨酸磷酸化位点;存在信号肽但是无跨膜结构域,二级结构由30.74%α螺旋、13.92%延伸链和40%无规则卷曲组成;且与水稻、玉米等其他植物的APX具有高度的同源性。电子克隆获得了完整的甘蔗APX基因全长cDNA。

英文摘要：

In silico cloning was a new strategy of gene cloning developed with the development of genome,EST projects and bioinformatics.A APX gene from Saccharum was cloned in silico cloning.A APX gene was cloned by blasting the EST database and using the bioinformatics soft with the Oryza sativa OsAPX2 as a querying probe.Sequence analysis showed that the in silico cloned cDNA is 1110base pairs long with a complete open reading frame（ORF） containing 975 nucleotides encoding a protein of 324 amino acid and belong to the hydrophobic proteins.The encoding protein of S-APX2 possessed Heme binding site,Substrate binding site,K＋ binding site,Ascorbate-peroxidase,Plant_peroxidase_like Superfamily domains and was predicted to locate in cell mitochondria,with five serine phosphorylation site,nine threonine phosphorylation site,and one tyrosine phosphorylation site.The signal peptide were found in the protein sequence but not found trans-membrane region.The protein contains 30.74% of α-helix,13.92% of extended strand and 55.34% of random coil.Bioinformatic analysis showed that the aminoacid encoded by this gene in saccharum was highly homologous with those encoded by APX gene in rice and maize.The in silico cloned cDNA is a APX gene of Saccharum.