鸡败血霉形D9604株pMGA基因的序列测定(英文)  

Sequencing of pMGA Gene of Mycoplasma gallisepticum Chinese Strain D9604

作　　者：丁铲[1] 戴亚斌[1] 于圣清 刘晓文[1] 王晓泉 

机构地区：[1]中国农业科学院家禽研究所,江苏扬州225003

出　　处：《中国家禽》2003年第z1期60-71,共12页China Poultry

摘　　要：对鸡败血霉形体(Mycoplasma gallisepticum,MG)D9604株基因文库中初步估测含有5个pMGA基因的重组质粒MD-411采用不同组合的限制性内切酶进行酶切,根据酶切片段大小及酶切位点绘制了9.2 kb外源片段的物理图谱。然后,选用Hind Ⅲ将该外源片段酶解成1.7 kb、3.1 kb和4.2 kb 3个片段,将它们分别亚克隆到pBluescript SK(+)中,获得了3个亚克隆子M-1、M-2和M-3,并进一步采用核酸外切酶Ⅲ缺失法构建了M-2和M-3的缺失子系列。经测序和分析获得了外源片段全序列。结果表明,质粒MD-411中外源片段长度为9040 bp,其中含3个完整和2个不完整的pMGA基因,按顺序分别命名为D-pMGA1.1、D-pMGA1.2、D-pMGA1.3、D-pMGA1.4和D-pMGA1.5。D-pMGA1.2、D-pMGA1.3和D-pMGA1.4等3个完整的pMGA基因阅读框分别为1 959 bp、2 034 bp和2 109 bp。D-pMGA1.1首部不完整,阅读框长633 bp。D-pMGA1.5尾部不完整,阅读框长1 158 bp。将D-pMGA基因与已报道的MG S6株和F株的pMGA基因序列进行了比较分析,探讨了不同MG菌株间pMGA基因的相似性、基因启动子结构的差异以及间隔区GAA重复序列对转录调控的影响等。Recombinant plasmid MD-411 estimated preliminarily to contain five pMGA genes was screened from gene library of Mycoplasma gallisepticum strain D9604. It was digested with various combinations of restriction enzymes. The physical pattern of 9.2 kb fragment in it was determined based on the sizes of restriction fragments and the cut-sites of restriction enzymes. 1.7 kb, 3.1 kb and 4.2 kb fragments were obtained when the 9.2 kb fragment was digested with Hind Ⅲ and subcloned to pBluescript SK(+). Three subclones, M-1, M-2 and M-3, were obtained and deletion mutant series of M-2 and M-3 were constructed by the use of exonuclease. The entire sequence of 9.2 kb fragment wasdetermined after sequence analysis. It was 9 060 bp in length and contained three complete and two incomplete pMGA genes designated as D-pMGA1.1, D-pMGA1.2, D-pMGA1.3, D-pMGA1.4 and D-pMGA1.5, respectively. The openreading frames of three complete genes were 1959 bp (1.2), 2034 bp(1.3) and 2109 bp(1.4), respectively. The incomplete open reading frames of D-pMGA1.1 with deletion at head and pMGA1.5 with deletion at tail were 633 bp and 1,158 bp, respectively. D-pMGA gene and other pMGA genes of MG strains S6 and F reported previously were compared in this study, and the similarity of pMGA genes from different MG strains, the differences in promoter structures and effects of GAA repeat sequences in intergenic regions on transcriptive regulation were discussed.

关 键 词：鸡败血霉形体 pMGA多基因家族 序列分析 

分 类 号：S83[农业科学—畜牧学]