油茶脂氢过氧化物裂解酶基因的克隆与序列分析

Cloning and sequence analysis of a fatty acid hydroperoxide lyase gene from Camellia oleifera

以油茶近成熟种子为材料,根据油茶EST文库中已知的脂氢过氧化物裂解酶EST序列,利用3’RACE与5’RACE技术,克隆到脂氢过氧化物裂解酶的全长cDNA序列。该基因全长1648bp,,包含一个1476bp开放阅读框长,编码491个氨基酸,5’与3’非编码分别为52bp、121bp。预测该蛋白相对分子量为54.7779KDa,等电点为6.77,是个叶绿体转运肽,N端包含有22个疏水氨基酸残基组成的序列,不仅具有转运肽富含的丝氨酸,还含有大量转运肽中很少存在的脯氨酸。多序列比对发现油茶脂氢过氧化物裂解酶核苷酸序列与茶的相似性达到96%,因此将该基因命名coHPL。

A cDNA library and a of Camellia oleifera were constructed.According to the fatty acid hydroperoxide lyase EST sequences of Camellia oleifera,a specific primer was designed,the fatty acid hydroperoxide lyase gene was cloned from Camellia oleiferawith 3＇RACE and 5＇RACE,respectively. This gene is 16 48 bp in length,including 51 bp of 5＇ untranslated region and 121 bp of 3＇ untranslated region. It has an open reading frame of 1 476 bp,encoding aprotein of 491 amino acid residues with protein molecular weight of 54 777.9 Da and isoelectric point of 6.77. A chloroplast transfer peptide was predicted,contains 22 hydrophobic amino acid residue in N-terminal,rich in serine and praline,however,the latter is rarely in transfer peptide.The alignment of amino acids sequence reveals that the comparability of Camellia oleifera and Camellia sinensis is 96%. This gene is named coHPL.