摘 要 ：晚期胚胎丰富（Late Embryogenesis Abundant, LEA）蛋白是植物在干旱胁迫下响应并被描述为具有潜在的抗旱功能的一类重要的抗旱蛋白。通过建立干旱胁迫下长春花（Catharanthus roseus）的cDNA文库并进行测序筛选分析，首次分离得到Crlea（Crlea for Catharanthus roseus late embryogenesis abundant）全长基因。该基因具有492 bp的开放读码框，编码163个氨基酸，其中偏性氨基酸含量占总蛋白的55.9%。同源性分析表明该假定蛋白与胡萝卜（Daucus carota）LEA DC3 的同源性达69%。亲水性分析表明具有极强的亲水性。为进一步验证CrLEA蛋白的功能，构建了Crlea基因的原核表达载体并在大肠杆菌中对其表达进行了分析。结果表明，原核载体成功的表达了CrLEA蛋白，亲水性实验及热稳定性实验表明CrLEA蛋白具有极强的亲水性和热稳定性。
Abstract:Late Embryogenesis Abundant (LEA) proteins are one of the important proteins in stress response which have been described as having a potential role in drought tolerance. Crlea(Crlea for Catharanthus roseus late embryogenesis abundant) gene was first cloned from cDNA library of Catharanthus roseus under drought stress through sequencing screening method. The sequence analysis of the Crlea gene showed a complete 492 bp ORF encoding a putative 163 amino acids polypeptide with a biased amino acid of 55.9% to total component. Homology analysis indicated a 69% similarity between CrLEA protein and carrot （Daucus carota）LEA DC3 protein. Hydrophobicity analysis found that CrLEA protein was extremely hydrophilic. For further identifying the function of CrLEA protein, prokaryotic recombinant vector of Crlea gene was constructed and the expression in E.coli was studied. Results showed recombinant CrLEA protein was successfully expressed in E.coli. Hydrophilic and heat-stable analysis of recombinant CrLEA protein showed a strong hydrophilic and heat-stable ability.