小白杏脂氧合酶基因PaLOX的克隆与序列分析

Cloning and sequence analysis of lipoxygenase gene(LOX) from Xiaobai apricots

[目的]克隆小白杏(Prunus armeniaca)PaLOX基因全长并对其进行序列分析。[方法]根据已有的ESTs序列,设计3'和5'端RACE引物,利用RT-PCR和RACE技术克隆小白杏PaLOX基因c DNA全长。[结果]PaLOX c DNA全长序列为2 723 bp,含有一个1 002 bp的ORF开放阅读框,编码334个氨基酸,含有PLAT高度保守的特异结构域,预测蛋白质的相对分子质量为26.558 1 k Da,推测理化等电点为8.77,分子式为C1689H2635N459O490S13;该蛋白主要表现为亲水性,α-螺旋和延伸链则散布于整个蛋白质中,空间结构不稳定,无信号肽和跨膜结构,可能存在于线粒体中。进化分析表明,PaLOX氨基酸序列与梅、碧桃、苹果、梨、草莓等蔷薇科聚为一类,相似性依次为98%、99%、78%、77%、63%。[结论]获得了编码小白杏脂氧合酶的基因PaLOX全长序列,登录号为KM067451。

[ Objective] Cloning and sequence analysis of full -length PaLOX gene in Xiaobai apricot （Prunus armeniaca）. [ Methods] Full -length PaLOX gene cDNA was isolated from Xiaobai apricot fruit according existed ESTs sequence, designed 3＇ and 5＇ end of the RACE primer s, RT - PCR and RACE were used . [ Results ] The cDNA length of the PaLOX gene was 2 723 bp long and contained a 1 002 bp open reading frame （ORF） which encoded 334 amino acids, contained plat that had highly conservative specific domain structure. It was forecasted the relative molecular mass of the LOX gene encoding the protein was 26. 558 1 kDa, and the physical and chemical isoelectric point is was 8.77, formula was C1689 H2635 N459 049o S13 ; The protein was mainly characterized by hydrophilic, alpha helix and chain extension was spread in the whole protein. Spatial structure was not stable, no signal peptide and transmembrane helix, maybe existing in the mitochondria. Through analyzing the evolutionary tree, PaLOX amino acid sequence gathered with rosaceae such as plum, prunus persica, apples, pears and strawberries, showed high similarity were 98% ,99% ,78% ,77% and 63% respectively in turn and then a registration genes No. KM067451 was ob- tained. [ Conclusion] PaLOX sequence encoding length of lipoxygenase genes was obtained in Xiaobai apricot.