摘要
从羊驼皮肤中提取总RNA,利用RT-PCR技术,扩增了羊驼显性白毛控制基因（KIT）cDNA序列（DQ450844）,并与其它动物相应区域作了同源性比较,结果表明：羊驼KIT基因exon10-19 cDNA长1 044 bp,编码含347个氨基酸残基的蛋白;蛋白质同源性比较显示,羊驼与牛、羊、猪、人、马、猩猩等的同源性大于98%,与鼠的同源性为95%。羊驼aa2编码缬氨酸,而猪、人与牛等动物则编码异亮氨酸,均属于非极性氨基酸;羊驼aa201编码脯氨酸,是非极性氨基酸,而猪、人与牛等动物则编码丝氨酸,是不带电荷的极性氨基酸;羊驼aa344编码精氨酸,而猪、人与牛等动物则编码赖氨酸,均为带正电荷的极性氨基酸。蛋白质二级结构及功能分析结果显示：此二级结构中含有大量的α-螺旋;该蛋白编码肥大细胞/干细胞生长因子,属于酪氨酸激酶受体家族,其蛋白激酶活性位点位于248~260之间。本研究结果将为深入研究KIT基因与羊驼毛色遗传的关系奠定一定的理论基础。
Three primers were designed to amplify the fragments of exon10 to exon14,exon13 to exon17 and exon16 to exon19 in alpacas.These fragments were 414,539 and 426 bp,respectively.1 044 bp cDNA sequence of KIT gene,spanned from exon10 to exon19,was obtained by contig software,and submitted to GenBank（DQ450844）.The nucleotide sequence was aligned with the corresponding part of other animals,and the similarity was above 94%,which indicated that the sequences were homologous.It was confirmed that the sequence obtained in this study was the KIT gene of alpacas.And the deduced polypeptide was got by the translation software and it coded 347 amino acids.The multiple sequence alignments revealed that the similarity of alpacas KIT sequence were above 95% with other species.Three amino acid substitutions were detected in the polypeptide coded by exon10-19 of KIT gene in alpacas,which were I→V at the position of 2,S→P at the position of 201 and K→R at the position of 344.And bioinformatics analysis indicated that there was much alpha-helix in the secondary structure;And the protein encoded the mast/stem cell growth factor receptor.These results would be the foundation of further researching the association between KIT gene and coat color of alpacas.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2009年第4期493-499,共7页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家自然科学基金(30800807
30571070)
