牦牛KRTAP6、FASN基因多态性及FASN基因突变与乳品质性状关联研究

发布时间：2018-06-06 13:04

本文选题：牦牛 + KRTAP6家族基因　；参考：《甘肃农业大学》2017年硕士论文

【摘要】：角蛋白关联蛋白(Keratins-associated proteins,KRTAPs)是毛纤维的主要结构成分,由KRTAPs基因家族编码,KARTAP6基因家族属于高甘氨酸/酪氨酸角蛋白(HGT-KRTAPs)基因家族,其突变影响毛纤维细度。脂肪酸合成酶(Fatty acid synthase,FASN)是脂肪酸合成代谢的关键酶,在动物体脂和乳脂的脂肪酸合成过程中发挥着关键作用。本研究应用PCR-SSCP技术检测甘南牦牛、天祝白牦牛、青海牦牛和野血牦牛KRTAP6家族基因编码区及FASN基因启动子区、第34外显子突变,分析其多态性和序列变异特征;结合甘南牦牛乳品质性状测定,分析FASN基因突变对乳品质性状的影响。主要结果为:1.牦牛KRTAP6家族基因编码区多态性较丰富。(1)KRTAP6-1基因编码区检测到A_1、B_1、C_1、D_1、E_1 5种等位基因,序列比对发现4处SNPs及1处45bp的插入/缺失突变,其中非同义突变c.173GC和c.175GT导致氨基酸残基p.Cys58Ser和p.Gly59Cys的改变,45bp的插入/缺失突变导致16个氨基酸残基的缺失;等位基因A_1频率56.5%~76.0%,为优势等位基因;甘南牦牛PIC值0.222呈低度多态,其他3个牦牛群体PIC值0.393~0.467呈中度多态。(2)牦牛KRTAP6-2基因编码区检测到A_2、B_2和C_23种等位基因,序列比对发现3处SNPs和1处6bp的插入/缺失,其中非同义突变c.248AG导致p.Tyr19Cys的氨基酸残基改变,6bp的插入/缺失突变导致2个氨基酸残基的缺失;等位基因A_2频率73.2%~87.3%,为优势等位基因;甘南牦牛PIC值0.387呈中度多态,其他3个牦牛群体PIC值0.203~0.246呈低度多态。(3)牦牛KRTAP6-4基因编码区检测到A_3、B_3、C_3、D_3和E_3 5种等位基因,序列比对发现6处SNPs,其中c.118AG的非同义突变导致编码氨基酸残基p.Ser40Gly的改变;等位基因A_3频率73.7%~82.8%为优势等位基因;4个牦牛群体PIC值0.265~0.387呈中度多态。(4)甘南牦牛KRTAP6-1、KRTAP6-2和KRTAP6-4基因编码区显著偏离Hardy-Weinberg平衡状态。2.序列比对及聚类分析发现牦牛KRTAP6-1、KRTAP6-2和KRTAP6-4基因位于第1号染色体上;牦牛KRTAP6-1基因外显子区碱基序列与普通牛、山羊和绵羊的同源性最高,系统进化与其亲缘关系远近一致。3.牦牛FSAN基因启动子区和第34外显子多态性较丰富。(1)启动子区检测到3种等位基因A,B和C,序列比对发现c.1-1948.TC和c.1-1910CA的碱基突变;等位基因A频率74.4%~75.2%为优势等位基因;PIC值0.366~0.376为中度多态。(2)第34外显子区检测到2种等位基因D和E,序列比对发现c.15281+74 AT的碱基突变;等位基因D频率77.6%~79.5%为优势等位基因;3个牦牛群体PIC值0.272~0.286为中度多态。(3)启动子区和第34外显子区突变位点间形成4种单倍型,其中单倍型D1A2频率最高为66.74%,D1B2型频率最低为6.96%;两区域突变位点间存在一定程度连锁关系且接近连锁平衡状态。4.FASN基因突变影响甘南牦牛部分乳品质性状。启动子区基因型AA个体的乳脂率显著高于基因型AB和AC个体(P0.05);第34外显子区基因型DD个体乳脂率显著高于基因型DE个体(P0.05),而基因型DE个体乳糖百分含量显著高于DD型个体(P0.05)。
[Abstract]:Keratins-associated proteins (KRTAPs) is the main structural component of wool fiber, which is encoded by the KRTAPs gene family. The KARTAP6 gene family belongs to the high glycine / tyrosine keratin (HGT-KRTAPs) gene family, and its mutation affects the fineness of the wool fiber. The fatty acid synthase (Fatty acid synthase, FASN) is a fatty acid synthesis generation. The key enzyme of Xie is playing a key role in the synthesis of fatty acid in animal body fat and milk fat. In this study, the PCR-SSCP technique was used to detect the gene coding region of Gannan yak, Tianzhu white yak, Qinghai yak and wild blood yak, and FASN gene promoter region, thirty-fourth exon mutation, analysis of polymorphism and sequence variation characteristics; The effects of FASN gene mutation on the quality of milk quality were analyzed in Gannan yak milk quality traits. The main results were: 1. yak KRTAP6 family gene coding region polymorphism was rich. (1) KRTAP6-1 gene coding region detected 5 alleles A_1, B_1, C_1, D_1, E_1, sequence alignment found 4 SNPs and 1 45bp insertion / deletion mutation, which is not The synonymous mutations c.173GC and c.175GT lead to changes in the amino acid residues p.Cys58Ser and p.Gly59Cys, and the insertion / deletion mutation of 45bp leads to the deletion of the 16 amino acid residues; the A_1 frequency of the allele 56.5%~76.0% is the dominant allele; the PIC value of the Gannan yak is 0.222 low polymorphism, and the PIC value 0.393~0.467 of the other 3 yak populations is moderately polymorphic. (2) A_2, B_2 and C_23 alleles were detected in the yak KRTAP6-2 gene coding region. Sequence alignment found 3 SNPs and 1 6BP insertion / deletion, in which the non synonymous mutation c.248AG leads to the change of the amino acid residues in p.Tyr19Cys, and the insertion / deletion mutation of 6BP leads to the loss of 2 amino acid residues, and the allele A_2 frequency 73.2%~87.3% is the dominant allele. The PIC value 0.387 of Gannan yak was moderately polymorphic and the PIC value 0.203~0.246 of the other 3 yak populations showed low polymorphism. (3) the 5 alleles of A_3, B_3, C_3, D_3 and E_3 were detected in the yak KRTAP6-4 gene coding region, and the sequence alignment found 6 SNPs, in which the non synonymous process of c.118AG resulted in the alteration of the encoded amino acid residues; The _3 frequency 73.7%~82.8% was the dominant allele; the PIC value of 4 yak populations was moderately polymorphic. (4) KRTAP6-1, KRTAP6-2 and KRTAP6-4 genes in Gannan yaks, KRTAP6-2 and KRTAP6-4 genes were significantly deviated from the.2. sequence alignment of Hardy-Weinberg and cluster analysis found that the Yak's KRTAP6-1, KRTAP6-2 and KRTAP6-4 genes were on the first chromosome; The nucleotide sequence of the exons of the 6-1 gene was the highest with the common cattle, goats and sheep. The phylogenetic relationship was far and close to the.3. yak FSAN gene promoter and thirty-fourth exon polymorphism. (1) the promoter region detected 3 alleles A, B and C, and the sequence alignment found the base mutation of c.1-1948.TC and c.1-1910CA; The allele A frequency 74.4%~75.2% was the dominant allele; PIC 0.366~0.376 was moderate polymorphism. (2) 2 alleles D and E were detected in thirty-fourth exons, sequence alignment found the base mutation of c.15281+74 AT; the D frequency 77.6%~79.5% of the allele was the dominant allele; 3 yak populations PIC 0.272~0.286 was moderate polymorphism. (3) promoter region and (3) promoter region. Thirty-fourth exon mutation sites formed 4 haplotypes, in which the frequency of haplotype D1A2 was the highest and the D1B2 type frequency was the lowest 6.96%; there was a certain degree of linkage between the two loci and the linkage equilibrium state.4.FASN gene mutation affected the milk quality traits of Gannan yak. The milk fat of the promoter region genotype AA individual The rate was significantly higher than that of genotype AB and AC individuals (P0.05); thirty-fourth exon genotype DD individual milk fat rate was significantly higher than that of genotype DE individuals (P0.05), while the content of lactose in genotype DE was significantly higher than that of DD type individuals (P0.05).
【学位授予单位】：甘肃农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S823.85

【相似文献】