Ⅱ型促性腺激素释放激素受体基因组织表达与鸭繁殖性状杂种优势关系分析  

Association Analysis between Differences of GnRHR-Ⅱ Gene Expression with Reproduction Traits Heterosis in Duck Populations

作　　者：韩威[1,2] 李慧芳[1] 朱云芬[1] 束婧婷[1] 徐文娟[1] 宋迟[1] 

机构地区：[1]中国农业科学院家禽研究所,江苏扬州225003 [2]南京农业大学,江苏南京210095

出　　处：《中国畜牧兽医》2014年第11期212-217,共6页China Animal Husbandry & Veterinary Medicine

基　　金：国家自然科学基金项目(31172149);江苏省科技支撑计划项目(BE2011329)

摘　　要：试验旨在克隆鸭Ⅱ型促性腺激素释放激素受体(gonadotropin releasing hormone receptor-Ⅱ,GnRHR-Ⅱ)基因序列,研究其在鸭生殖轴组织中表达差异与繁殖性状的杂种优势关系。采用RT-PCR方法从鸭生殖轴组织中克隆出GnRHR-Ⅱ基因片段序列,利用Real-time PCR技术分析GnRHR-Ⅱ基因在不同产蛋期高邮鸭、金定鸭及其正反交组合生殖轴组织中的表达,并分析表达差异与繁殖性状杂种优势的关系。序列分析结果表明,克隆序列长度约500bp,属Ⅱ型GnRHR基因序列,与家鸡cGnRHR-Ⅱ序列的同源性达96%。从产蛋早期至高峰期,高邮鸭、金定鸭及其正反交组合垂体中GnRHR-Ⅱ基因的表达量均呈上调趋势,且金定鸭×高邮鸭杂交组合的表达量最高(P<0.01);下丘脑中GnRHR-Ⅱ基因表达量在高邮鸭、金定鸭中呈上调趋势,而在2个正反交组合中呈下调趋势。产蛋早期金定鸭和2个正反交组合卵巢中GnRHR-Ⅱ基因表达量极显著高于高邮鸭(P<0.01),至产蛋高峰期表达量明显下调。杂种优势率分析结果表明,2个正反交组合在42周龄产蛋数和42周龄种蛋受精率性状中都表现出正向杂种优势,在开产日龄和42周龄受精蛋孵化率性状中都表现出负向杂种优势。推测产蛋期前鸭卵巢中GnRHR-Ⅱ基因的暂时性高表达与开产日龄和42周龄产蛋数性状杂种优势相关,垂体组织中GnRHR-Ⅱ基因的持续高表达可能对产蛋高峰期的形成和维持具有重要作用。The objective of this study was to clone the sequence of duck type Ⅱ gonadotropin releasing hormone receptor （GnRHR-Ⅱ） gene, and to analyze the association of its expression levels with reproduction trait heterosis. RT-PCR method was used to clone GnRHR-Ⅱ gene fragments, and the expression levels during early laying days and laying fastigium period in Gaoyou duck, Jinding duck and crossed populations were tested by Real-time PCR method. Sequencing and homology analysis showed that the cloned duck GnRHR cDNA was about 500 bp in length, and it belonged to the avian type Ⅱ GnRHR isoforms. It was 96% identical to the cGnRHR-Ⅱ sequence reported in domestic chicken. From the early laying days to laying fastigium period, expression levels of GnRHR-Ⅱ gene in pituitary increased for Jinding duck, Gaoyou duck and crossed populations, with the highest expression levels in Jinding × Gaoyou hybrid group （P〈0.01） . The expression levels of GnRHR-Ⅱ gene in hypothalamus also increased for Jinding duck, Gaoyou duck, however, it decreased in two crossed populations. The expression levels of GnRHR-Ⅱ gene in ovary were significantly higher for Jinding duck and two crossed populations than Gaoyou duck （P〈0.01）, but it decreased during laying fastigium period. Compared to Jinding cluck and Gaoyou duck breeds, the two crossed populations had positive heterosis in 42-week production and 42-week egg fertilization percent, and negative heterosis in the first laying age and 42-week fertilized egg hatching rate traits. It suggested that the short-lived higher expression of ovary GnRHR-Ⅱ gene before early laying days be correlated with heterosis of the first laying age and 42-week production traits, and its higher expression levels in pituitary could aid to keep laying fastigium.

关 键 词：鸭 Ⅱ型促性腺激素释放激素受体基因 表达分析 杂种优势 

分 类 号：S814.8[农业科学—畜牧学]