【摘要】 目的对牦牛H-FABP基因进行克隆和序列分析,以期为进一步开展牦牛该基因与其肉质性状的相关分析,进行分子标记辅助选择以及基因定位、表达等研究提供理论基础。方法用特定引物对牦牛H-FABP基因进行PCR扩增并进行T-A克隆和测序,在此基础上使用RepeatMasker、DNAMAN4.0、BioEdit4.8.10、ClustalW1.81等生物信息学软件进行序列分析。结果牦牛H-FABP基因(已在NCBI上登录,登录号为DQ026674)由4个外显子和3个内含子组成,CDS序列全长为402bp,前体氨基酸数为133个。4个外显子大小分别为73bp、173bp、102bp和54bp;3个内含子大小分别为3460bp、1892bp和1495bp;外显子与内含子的连接区序列遵循通常的基因组成规律。外显子和内含子个数与普通牛、绵羊、山羊、猪、人、大鼠、小鼠、鸡、斑马鱼各物种相同。牦牛H-FABP基因序列中,重复序列所占比率为13.07%。内含子Ⅰ含有5个重复元件,包括1个SINE/Artiodactyls元件、1个SINE/MIR3元件、1个SINE/Bov-tA1元件和2个SINE/MIR元件;内含子Ⅱ无重复元件;内含子Ⅲ有3个重复元件,其中SINE/MIR元件、LINE/L2元件、SINE/Artiodactyls元件各1个。SINEs短重复序列所占比率为11.85%,哺乳动物分散性重复序列MIRs比率为6.44%。LINEs所占比率为1.22%,小于SINEs元件。其中,LINE1、BovB/Art2、L3/CR1重复元件以及LTR类反转录元件和DNA转座子元件在牦牛该基因区域中不存在。不同物种间在该基因编码区核苷酸序列和氨基酸序列上有较高的保守性。牦牛与普通牛、绵羊、山羊、猪、人、大鼠、小鼠、鸡、斑马鱼各物种在H-FABP基因编码区核苷酸序列上同源性大小分别为99.8%、97.8%、97.0%、92.8%、88.8%、83.3%、83.1%、76.4%、68.7%;相应的氨基酸序列间同源性大小为100%、96.9%、96.9%、92.4%、88.7%、85.7%、85.7%、77.4%、69.9%。结论牦牛H-FABP基因由4个外显子和3个内含子组成,其中外显子I、外显子Ⅱ、外显子Ⅲ和外显子Ⅳ大小分别为73bp、173bp、102bp和54bp,内含子I、内含子Ⅱ和内含子Ⅲ大小分别为3460bp、1892bp和1495bp。牦牛该基因区域含有较为丰富的重复序列元件且外显子与内含子的连接区序列遵循通常的基因组成规律。牦牛与普通牛、绵羊、山羊、猪、人、大鼠、小鼠、鸡、斑马鱼9个物种在H-FABP基因编码区核苷酸及氨基酸序列上具有较高的保守性。更多还原

【Abstract】 【Objective】The yak heart fatty acid-binding protein(H-FABP) gene was cloned and sequenced.This was then compared to the deduced amino acid sequence with the homologous H-FABP gene.It was also compared with the protein sequence of the H-FABPs in other species(including cow,sheep,goats,pigs,human,rats,mice,chicks and zebra-fish) retrieved from the GenBank.These comparisons were performed in order to provide a theoretical foundation for further research of the correlation of yak H-FABP gene and meat quality,molecular breeding,location and expression.【Method】The yak H-FABP gene was amplified using particular primers,cloned by T-A method and sequenced,based on this the nucleotide and amino acid sequences among different species were compared and analyzed by RepeatMasker、DNAMAN4.0、BioEdit4.8.10、Clustal W1.81 i.e,bio-softs【.Result】The number of exons and introns of yak H-FABP gene(GenBank Accession No: DQ026674) were as same as those in cow,sheep,goats,pigs,human,rats,mice,chicks and zebra-fish.They had 4 exons and 3 introns.The size of CDS sequence of the yak H-FABP gene,encoding 133 amino acid,was 402 bp.The size of exon I,exonⅡ,exonⅢ and exonⅣ was 73 bp,173 bp,102 bp and 54 bp respectively;while the size of intron I,intronⅡand intronⅢ was 3 460 bp,1 892 bp and 1 495 bp respectively.The junction sequence of exons and introns of yak H-FABP gene was in accordance with the law of gene composition.The rate of the repetitive sequence was 13.07% in the nucleotide sequence of yak H-FABP gene.Five repetitive elements were found in the intronⅠ,including a SINE/Artiodactyls element,a SINE/MIR3 element,a SINE/Bov-tA1 element and two SINE/MIR elements.No repetitive element was found in intronⅡ.Three repetitive elements were found in intron3,including a SINE/MIR element,a LINE/L2 element and a SINE/Artiodactyls element.The rate of the repetitive sequence was 11.85% for SINEs,6.44% for MIRs and 1.22% for LINEs respectively.In addition,LINE1,BovB/Art2,L3/CR1 repetitive elements,LTR anti-transcription element and DNA transposing element were not found in this sequence.The nucleotide sequence of the coding region and deduced amino-acid sequences among different species were quite conservative.The homology rates of nucleotide sequences of the coding region of H-FABP gene between the yak and cow,sheep,goat,pig,human,rat,mouse,chick and zebra-fish were 99.8%,97.8%,97.0%,92.8%,88.8%,83.3%,83.1%,76.4%,68.7% respectively,while the homology rates of amino-acid sequences were 100%,96.9%,96.9%,92.4%,88.7%,85.7%,85.7%,77.4%,69.9% respectively.【Conclusion】The yak H-FABP gene had 4 exons and 3 introns.The size of CDS sequence of the yak H-FABP gene,encoding 133 amino-acid,was 402 bp.The size of exon I,exonⅡ,exonⅢ and exonⅣ was 73 bp,173 bp,102 bp and 54 bp respectively;while the size of intron I,intronⅡand intronⅢ was 3 460 bp,1 892 bp and 1 495 bp respectively.There were many repetitive elements in the nucleotide sequence of yak H-FABP gene,and the junction sequence of exons and introns was accordance with the law of gene composition.The nucleotide sequences of the coding region and deduced amino acid sequences between yak and cow,sheep,goats,pigs,human,rats,mice,chicks and zebra-fish were quite conservative.更多还原