【摘要】 通过RT-PCR扩增出鸡β-防御素Gal-1、Gal-2和Gal-3基因的部分cDNA序列,大小分别为198、195和297bp。利用PCR技术扩增出鸡β-防御素Gal-1、Gal-2和Gal-3基因组DNA部分序列,大小分别为1176、1053和2454bp。经分析发现,2个内含子将鸡-β-防御素Gal-1、Gal-2和Gal-3基因的编码区分成3个外显子部分。第1个外显子编码绝大部分信号肽序列;第2个外显子编码信号肽羧基端极小部分序列、原片段序列与大部分成熟肽序列;第3个外显子编码小部分成熟肽序列。扩增到的鸡β-防御素Gal-1、Gal-2和Gal-3基因的两个内含子长度,分别为482和496bp,183和675bp,980和1280bp。鸡β-防御素基因编码区结构的这种组成与哺乳动物的β-防御素基因的不同,在哺乳动物中为1个内含子将β-防御素基因编码区分成2个外显子部分。Blast比较发现,鸡β-防御素Gal-1和Gal-2基因位于鸡的3号染色体连续克隆群Contig42.182上,并且这2个基因转录方向相反。Gal-3基因位于鸡的3号染色体连续克隆群Contig42.181和Contig42.182上,转录方向与Gal-1基因相同。更多还原

【Abstract】 The partial cDNA fragments of chicken β-defensin Gal-1, Gal-2 and Gal-3 genes, with the sizes of 198, 195 and 297 bp respectively, were amplified by reverse transcription-polymerase chain reaction (RT-PCR). The genomic DNA partial fragments of the Gal-1, Gal-2 and Gal-3 genes, with the sizes of 1176, 1053 and 2455 bp respectively, were amplified by PCR from chicken genome. Analysis of the sequence data showed that the chicken β-defensin gene comprised of three exons and two introns, which was different from that of mammalian β-defensin gene with two exons and one intron. The sizes of two introns of Gal-1, Gal-2 and Gal-3 genes were 482 and 496 bp, 183 and 675 bp, 980 and 1280 bp, respectively. Analysis with the Blast program showed that the β-defensin Gal-1 and Gal-2 genes were located on the contig42.182 of chromosome 3 and Gal-3 gene was located on the contig42.181 and contig48.182 of chromosome 3. The transcription orientation of Gal-1 was same with that of Gal-3 and contrary to that of Gal-2.更多还原