根据猪Toll样受体7基因(TLR7)序列设计、合成1对引物,直接从三元猪外周血淋巴细胞中提取总RNA,应用RT-PCR技术扩增三元猪TLR7全基因,并进行克隆和测序。测序结果表明,获得了三元猪TLR7全基因序列,其大小为3 160 bp,包含一个完整阅读框(3 153 bp),编码1 051个氨基酸残基,有15个潜在的N-糖基化位点和4个潜在的磷酸化位点,信号肽切割部位位于第29～30位氨基酸之间,跨膜基因序列为第844～866位。TLR7基因存在种属的差异性,亲缘关系越近,同源性越高。三元猪TLR7基因的成功克隆为进一步研究猪TLR7基因表达、生物学功能、揭示ssRNA病毒入侵宿主的致病机制以及猪抗病毒免疫及育种的相关研究奠定了基础。
One paiR of pRimeRs was designed and synthesized accoRding to the nucleic acid sequence of poRcine toll-like ReceptoR 7( TLR7) gene． The TLR7 gene fRom Sanyuan pig was amplified by RT-PCR fRom the total RNA extRacted fRom peRipheRal blood lymphocytes，and then cloned and sequenced． The Result showed that the full length of TLR7 gene sequence fRom Sanyuan pig was consisted of 3 160 bp，which included one open-Reading fRame( 3 153 bp) ，encoding 1 051 amino acid Residues． TheRe weRe fifteen potential N-glycosalation sites and fouR potential phosphoRylation sites． The cleavage sites of signal peptide weRe pRedicted to be in 29th oR 30th of the amino acid sequence， a nd the tRansmembRane helices in pRoteins was in 844 - 866th amino acid sequence． The Results of compaRative sequence analysis and phylogenetic tRee analysis indicated that the TLR7 gene had diffeRence of genus，and the neaReR the genetic Relationship， the higheR homology． This study paved the way foR futuRe study of poRcine TLR7 gene expRession，biological function，mechanisms of infection with ssRNA viRuses，antiviRal immunity and bReeding．
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