猪繁殖候选基因ERK2的克隆、表达及基因多态分析

 【目的】ERK2基因在细胞增殖和分化调控以及启动卵巢排卵的分子信号等过程中发挥重要作用,是影响猪繁殖性状的重要候选基因。本试验对猪ERK2基因序列、基因结构、基因多态性及其表达规律进行初步研究。【方法】以大白猪为材料,采用RT-PCR方法克隆了猪ERK2基因,Real-Time PCR测定该基因在猪各组织器官中的分布,并对该基因的结构和多态性进行分析。【结果】从猪卵巢组织中克隆获得ERK2基因部分cDNA序列,长1 888 bp,包括一个1 080 bp的开放阅读框,编码359个氨基酸与预测的猪ERK2基因、已报道的人和小鼠等的ERK2基因高度相似;猪ERK2基因在各组织中表达广泛,其中脾脏是表达量最高的组织,在脂肪组织、前后腿肌中基本不表达;猪ERK2基因定位于14号染色体,全长在22 kb以上,包含9个外显子和8个内含子;对第2—9外显子及内含子外显子交界处的内含子序列进行序列突变检测,共检测到11个SNPs和1个插入缺失突变,但绝大部分的变异都是在内含子区域,仅有1个SNP发生于3′UTR区域。【结论】猪ERK2基因cDNA为1 888 bp,编码359个氨基酸残基;在猪各组织中广泛分布,以脾脏的表达量最高;该基因由9个外显子和8个内含子组成,基因保守性较高,共检测到11个SNP和1个插入缺失突变均不在编码区中。

Cloning, Expression and Polymorphism Analysis of Pig ERK2 Gene for Reproduction Traits

【Objective】 Extracellular signal-regulated kinase-2 (ERK2) gene plays important roles in regulating cell proliferation and differentiation, as well as starting the ovulation of ovary. It is an important candidate gene for porcine reproduction traits. In this study, the pig ERK2 gene was cloned and its genomic organization, tissue expression patterns, and gene polymorphism were investigated.【Method】 In this study, the pig ERK2 gene was cloned by RT-PCR and its mRNA distribution in different tissues was studied by real time PCR, moreover, the ERK2 gene structure and polymorphisms were analyzed. 【Result】 The cloned pig ERK2 cDNA was 1 888 bp long, and contained an open reading frame of 1 080 bp, which encoded a peptide of 359 amino acid residues. The encoded ERK2 was highly similar with predicted pig ERK2 and the human and mouse counterpart. The ERK2 gene was widely expressed in many porcine tissues. The highest expression was found in spleen, however almost no expression in adipose tissue, muscle tissues from front and back legs. The pig ERK2 gene was located at the 14th chromosome, and composed of 9 exons and 8 introns. Variation detection of exon 2-9 and intron-exon boundary sequences indicated that a total of 11 SNPs and 1 indel were identified, most of which were in introns and only one was in 3’ UTR. 【Conclusion】The obtained cDNA of pig ERK2 gene was 1 888 bp long and encoded a 359-amino acid peptide. The ERK2 gene was found to express in many tissues of pig with highest level in spleen. The ERK2 gene comprised 9 exons and 8 introns and showed high conservation. A total of 11 SNP and 1 indel were found, but none of them was in coding regions.