猪肌肉生长抑制素基因侧翼区新微卫星标记的鉴定及分析  

Identification and Analysis of a Novel Microsatellite Marker Flanking Porcine Myostatin Gene (MSTN)

作　　者：姜运良[1,2] 李宁[1] 赵兴波[3] 胡晓湘[1] 刘兆良[1] 邓学梅[3] 吴常信[3] 杜立新[4] 曹积生 

机构地区：[1]中国农业大学农业生物技术国家重点实验室 [2]山东农业大学动物分子遗传育种实验室,泰安271018 [3]中国农业大学动物科技学院 [4]中国农科院畜牧所 [5]山东烟台益生种畜禽场

出　　处：《Acta Genetica Sinica》2004年第5期480-484,共5页

基　　金：国家重点基础研究发展规划项目 (编号 :G2 0 0 0 0 161);国家自然科学基金重点项目 (编号 :3 973 0 3 60 )资助~~

摘　　要：提取包含猪肌肉生长抑制素基因的BAC克隆 ,以EcoRⅠ进行酶切并回收其中大于 4kb的酶切产物 ,连接到pGEM 3zf(+)载体后得到了亚克隆。测序分析表明 ,插入片段不属于猪肌肉生长抑制素基因的一部分 ,但其中包含 13拷贝的 (TG)n重复。以该重复序列的侧翼设计引物对猪的基因组进行分析 ,得到了PCR扩增产物。对一个“双肌臀”大白猪家系进行PCR扩增及非变性聚丙烯酰胺凝胶分析的结果表明 ,该位点以并显性方式遗传 ,是一个新的微卫星标记。对莱芜猪、长白猪、大白猪、杜洛克、皮特兰、民猪和二花脸 7个品种的 381个无关个体的检测均显示该基因座只有两个等位基因 ,重复数分别为 13和 19,是一种多态性较低的微卫星标记。与包含该基因的序列(AY2 0 812 1)比对分析表明 ,该微卫星属于肌肉生长抑制素基因 (MSTN)侧翼区的一个分子标记 ,在猪肉用性状QTL的精细定位和MSTN功能分析中将发挥重要作用。In animal breeding,microsatellite marker plays an important role in constructing genetic maps,QTL mapping and function analysis of structural genes.Myostatin,also known as GDF8,is a negative regulator of skeletal muscle mass and,in swine,it is evidenced to be related to birth weight and average daily gain from 60 kg to 100 kg of body weight.In present study,by subcloning and sequencing,we identified a novel microsatellite marker which is useful for fine QTL mapping for meat traits.A BAC clone containing porcine MSTN was extracted and digested with EcoRⅠ to recover the fragment of >4 kb for subcloning in pGEM-3zf(+).Sequencing and alignment results showed that this subcloned fragment was not from porcine MSTN,but included a tandem repeat of (TG)_(13),which is a novel microsatellite marker (GenBank accession number:AF454400) flanking MSTN.To exclude its vector origin we designed specific primers flanking this marker and successfully amplified this fragment from porcine genome.Through a pedigree analysis of a double-muscled Yorshire strain,we found that it is inherited in a co-dominant manner.We also checked the gene frequencies of this locus in 381 unrelated individuals of 7 pig breeds,namely Laiwu,Landrace,Yorkshire,Duroc,Peterian,Min and Erhualian.Only two alleles were detected,the repeating number of which are 13 (allele A) and 19 (allele B) respectively,which indicated that it is a low (poly)morphic microsatellite marker.In addition,the frequencies of the two alleles are different between the two types of pig breeds,while allele A is dominant in Chinese local breeds,allele B is dominant in imported breeds.Alignment with AY208121 indicate that this locus is located 42 kb downstream of porcine MSTN.We speculate that this microsatellite DNA is an important marker both in fine QTL mapping for meat traits and in the expression study of porcine MSTN.

关 键 词：猪 微卫星 肌肉生长抑制素基因 

分 类 号：Q953[生物学—动物学]