昆明犬IGF1基因在肝脏中的表达特征及遗传多样性分析  

Expression characteristics and genetic diversity analysis of IGF1 gene in the liver of Kunming dogs

作　　者：韦云芳 李飞翔 汪斌 陈方良 魏红江 WEI Yunfang;LI Feixiang;WANG Bin;CHEN Fangliang;WEI Hongjiang(College of Animal Science and Technology,Yunnan Agricultural University,Kunming 650201,China;Yunnan Province Key Laboratory for Porcine Gene Editing and Xenotransplantation,Kunming 650201,China;Kunming Police Dog Base,Ministry of Public Security,Kunming 650204,China;Key Laboratory of Police Dog Technology of Ministry of Public Security,Kunming 650204,China)

机构地区：[1]云南农业大学动物科学技术学院,昆明650201 [2]云南省小型猪基因编辑与异种器官移植重点实验室,昆明650201 [3]公安部昆明警犬基地,昆明650204 [4]警犬技术公安部重点实验室,昆明650204

出　　处：《黑龙江畜牧兽医》2024年第4期108-114,共7页Heilongjiang Animal Science And veterinary Medicine

基　　金：云南省科技厅基础研究专项(202101AT070035);公安部科技强警基础工作专项(2017GABJC20)。

摘　　要：为了探究IGF1基因在不同生长发育阶段昆明犬肝脏中的表达特征,并筛选与昆明犬体重和体尺性状相关的单核苷酸多态性(single nucleotide polymorphism,SNP)位点,试验首先采用实时荧光定量PCR方法检测IGF1基因在不同年龄段昆明犬肝脏中的mRNA表达水平,然后分别针对IGF1基因5′和3′侧翼序列、外显子1~4和内含子1设计引物,采用PCR-单链构象多态性(SSCP)技术对昆明犬IGF1基因单核苷酸多态性(SNP)位点进行筛查,通过测序分析其突变情况,统计该SNP位点的基因型频率和基因频率及遗传多样性指标[纯合度(homozygosity,Ho)、杂合度(heterozygosity,He)和有效等位基因数(number of effective alleles,Ne)],最后分析该SNP位点与昆明犬体重和体尺性状的关联性。结果表明:IGF1基因在5个年龄段的昆明犬肝脏中均有表达,且表达量随着月龄的增大呈现逐渐下降的趋势;与2月龄比较,6,12,20,30月龄昆明犬肝脏中IGF1基因的相对表达量均极显著降低(P<0.001)。昆明犬IGF1基因仅外显子3中识别到1个SNP位点,其他区域未识别到SNP位点。该位点位于外显子3第464位核苷酸处,发生了T→C的点突变,但氨基酸未变,命名为T464C位点。T464C位点在昆明犬群体中共存在两种基因型,分别为TT纯合型和TC杂合型,其中优势基因型为TT纯合型,优势等位基因为T,表现为低度多态(PIC<0.25),Ho为0.97,He为0.03,Ne为1.03,在昆明犬群体中处于Hardy-Weinberg平衡状态。昆明犬IGF1基因T464C位点TT纯合型个体胸深、头长显著高于TC杂合型个体(P<0.05)。说明IGF1基因在昆明犬生长发育过程中具有重要作用,T464C位点可作为昆明犬品种培育的潜在辅助选择标记。In order to explore the expression characteristics of IGF1 gene in the liver of Kunming dogs at different growth and development stages,and to screen single nucleotide polymorphism(SNP)sites associated with weight and body size traits of Kunming dogs,firstly,real-time fluorescence quantitative PCR was used to detect the mRNA expression level of IGF1 gene in the liver of Kunming dogs of different ages.Then primers were designed for the 5′and 3′flanker sequences of IGF1 gene,exons 1-4 and introns 1,and PCR-single strand conformation polymorphism(SSCP)technology was used to screen the SNP loci of IGF1 gene in Kunming dogs,and the mutations were analyzed by sequencing.Genotype frequency,gene frequency and genetic diversity indicators(homozygosity[Ho],heterozygosity[He]and number of effective alleles[Ne])of the SNP loci were measured.Finally,the correlation between the SNP loci and the body weight and body size traits of Kunming dogs was analyzed.The results showed that IGF1 gene was expressed in the liver of Kunming dogs at 5 ages,and the expression level showed a decreasing trend with the increase of age.Compared with 2 months of age,the relative expression of IGF1 gene in the liver of dogs 6,12,20,30 months of age was significantly decreased(P<0.001).Only one SNP loci was identified in exon 3 of IGF1 gene in Kunming dogs,and no SNP locus was identified in other regions.This site was located at the 464 nucleotide of exon 3 and had a T→C point mutation,but the amino acid had not changed,and was named T464C locus.There were two genotypes in the T464C locus in Kunming canine population,TT homozygous and TC heterozygous.The dominant genotype was TT and the dominant allele was T,showing low polymorphism(PIC<0.25),Ho(0.97),He(0.03)and Ne(1.03).It was in Hardy-Weinberg equilibrium in Kunming dog population.The chest depth and head length of TT homozygous type individuals with T464C locws of IGF1 gene were significantly higher than those of TC heterozygous type individuals(P<0.05).These results indicated that IGF1 gen

关 键 词：昆明犬 胰岛素样生长因子1(IGF1) 差异表达 单核苷酸多态性(SNP) 遗传多样性 关联性分析 

分 类 号：S829.2[农业科学—畜牧学]