ACSL5基因对肉牛胴体性状及脂肪合成通路甘油三酯的影响

发布时间：2018-01-13 10:01

本文关键词：ACSL5基因对肉牛胴体性状及脂肪合成通路甘油三酯的影响　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：长链脂酰辅酶A合成酶5(ACSL5)是ACSLs家族中的重要一员,是动物机体脂肪酸β氧化和甘油三酯合成、代谢过程中的关键酶。但ACSL5基因对肉牛脂肪酸合成、脂肪沉积和胴体性状是否亦具有相同的影响作用尚不清楚。本实验通过肉牛群体和细胞水平对ACSL5基因调控脂肪代谢作用进行了研究分析,为进一步解析ACSL5的功能及应用于肉牛分子辅助育种提供技术依据。本实验以肉用牛为研究对象,测定了354头中国西门塔尔牛的胴体与肉质性状,采用PCR-RFLP对该群体进行了ACSL5基因多态性检验,分析了其SNPs与肉牛群体胴体性状和肉质性状的相关性。进而,构建了牛ACSL5过表达载体PBI-CMV3-ACSL5和sh RNA干扰载体,采用电穿孔方法转染牛前体脂肪细胞,解析了ACSL5基因表达水平变化(过表达和沉默后)对细胞的脂肪代谢通路中甘油三酯合成的作用。结果表明,在中国西门塔尔牛的5’侧翼序列中筛查到两个SNP位点g.33185918GA和g.33186348CT,与中国西门塔尔肉牛的胴体和肉质性状具有显著的相关性。g.33185918GA位点,相比于AA纯合基因型个体,中国西门塔尔牛群体中携带G等位基因(GA基因型或GG基因型)的个体表现出更高的瘤网皱胃重(7.48±0.91 kg)、瓣胃重(3.94±0.59 kg)、睾丸重(0.69±0.13 kg)和脂肪颜色评分(2.97±0.74,p0.05);而AA纯合基因型个体表现出更高的排酸p H值(5.91±0.78 kg,p0.05);其中,瘤网皱胃重和排酸p H值均表现为极显著差异(p0.01)。g.33186348CT位点,与CC纯合基因型中国西门塔尔牛个体相比,携带T等位基因(CT基因型和TT基因型)的个体表现出了更高的胴体脂肪覆盖率(50.38±20.46%)、腰部肉厚(6.89±0.87 cm)和肝脏重(6.33±1.24kg),而携带CC纯合基因型的个体却表现出更高的后蹄重(3.39±1.03 kg)、后腿长(79.87±3.98 cm)、生殖器脂肪重(0.91±0.37 kg)和胴体长(139.50±7.79 cm);其中,肝脏重、后腿重、肾脏重、睾丸重和脂肪覆盖率均有极显著差异(p0.01)。说明,ACSL5基因调控区域的SNPs与中国西门塔尔牛部分胴体性状和肉质性状具有相关性。在牛前体脂肪细胞中进行ACSL5基因的过表达和沉默后处理后检测细胞脂肪合成通路中甘油三酯的变化。结果表明,ACSL5基因在牛前体脂肪细胞中过表达能显著提高细胞中甘油三酯的含量(p0.01);而当牛前体脂肪细胞中沉默ACSL5基因表达后,细胞内甘油三酯合成量有降低趋势,但并不显著(p0.05)。综上所述,ACSL5基因调控区域发生的SNP:g.33185918GA和g.33186348CT均与中国西门塔尔肉牛部分胴体和肉质性状存在相关性;同时ACSL5基因对牛前体脂肪细胞甘油三酯的合成具有一定促进作用。研究结果可为进一步解析ACSL5的功能及应用于肉牛分子辅助育种提供技术依据。
[Abstract]:Long chain acyl coenzyme A synthetase 5 (ACSL5) is an important member of the ACSLs family, is the animal body fatty acid oxidation and triglyceride synthesis, the key enzyme in the metabolic process. But ACSL5 gene on beef fatty acid synthesis, fat deposition and carcass traits are also have the same effect is not clear. Through the experiments of beef cattle populations and cellular levels of ACSL5 gene regulating fat metabolism were analyzed for further analysis the function and application of ACSL5 in beef cattle molecular breeding to provide technical basis. In this experiment, the beef cattle as the research object, measured 354 Chinese Simmental Cattle Carcass and meat quality traits, PCR-RFLP is used test of ACSL5 gene polymorphism of the group, to analyze the correlation between the SNPs group and beef carcass traits and meat quality. Then, constructed a bovine ACSL5 expression vector PBI-CMV3-ACSL5 and sh RNA Interference vector by electroporation into bovine preadipocytes, the expression of the ACSL5 gene (overexpression and silencing) role of triglyceride fatty metabolic pathway on cell synthesis. The results showed that in China Simmental 5 flanking sequence screened two SNP loci g.33185918GA and g.33186348CT, with correlation.G.33185918GA significant sites with carcass and meat quality traits in Simmental beef cattle China, compared to the AA genotype, Chinese Simmental population carrying G allele (GA genotype or GG genotype) of the individuals showed tumor net abomasum higher weight (7.48 + 0.91 kg (3.94), heavy omasum 0.59 + kg), testis weight (0.69 + 0.13 kg) and fat color score (2.97 + 0.74, P0.05); and AA genotype showed Acid P higher H value (5.91 + 0.78 kg, P0.05); the tumor weight and net abomasum P acid H value showed significant difference (P0.01).G.33186348CT loci, and CC homozygous gene compared China Simmental individuals carrying T allele (CT and TT genotypes) individuals showed higher carcass fat coverage (50.38 + 20.46%), the waist of the flesh (6.89 + 0.87 cm) and liver weight (6.33 + 1.24kg), while carrying CC homozygous genotype showed higher after hoof weight (3.39 + 1.03 kg) and long hind legs (79.87 + 3.98 cm), genital fat weight (0.91 + 0.37 kg) and carcass length (139.50. 7.79 cm); among them, liver weight, kidney weight, leg weight, testis weight and fat coverage rate were significantly different (P0.01). The results showed that, ACSL5 gene regulatory region SNPs is associated with China Simmental some carcass traits and meat quality traits. In bovine preadipocyte cells were detected after postprocessing. Expression and gene silencing by ACSL5 Changes in fatty triglyceride synthesis pathway. The results showed that the ACSL5 gene in bovine preadipocyte overexpression can significantly improve the content of triglyceride (P0.01); and when the silencing of ACSL5 gene expression in bovine preadipocyte, intracellular triglyceride synthesis quantity has decreased, but not significant (P0.05). In summary, both the regulatory regions of ACSL5 SNP:g.33185918GA and g.33186348CT are associated with China part of Simmental Beef Cattle Carcass and meat quality traits; at the same time the synthesis of ACSL5 gene of bovine preadipocyte triglyceride has certain stimulative effect. The research results can be used for further analysis of the function and application of ACSL5 in beef cattle molecular breeding to provide technical basis.

【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S823

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