1 College of Grassland Ecology and Animal Husbandry and Veterinary, Xilin Gol Vocational College, Xilinhot 026000, China; 2 Xilinhot Animal Husbandry Station, Xilinhot 026000, China; 3 Xilin Gol League Agricultural Research Institute, Xilinhot 026000, China; 4 College of Life Science, Inner Mongolia Agricultural University, Huhhot 010000, China; 5 Gand Farm Xilin Gol League Meats Co., Ltd, Xilinhot 026000, China
Abstract：Meat quality traits are important economic value in sheep (Ovis aries) breeding. Lipoprotein lipase (LPL) is known as an important enzyme in the metabolism of lipids and lipoproteins in animal organisms, which belongs to the lipase family. LPL is mainly synthesized and secreted by adipose cells, skeletal muscle cells, myocardial cells, mammary cells and macrophages. Enzyme activity is regulated by nutritional factors and hormone levels. The A384T single nucleotide polymorphism (SNP) exists in the exon 3 of sheep LPL gene, and this SNP has been confirmed to have a certain relationship with sheep meat quality traits. Ujimqin sheep is the most important breed of Mongolia sheep population with fat-tailed, high quality meat and carpet wool, and have sound body conformation, strong walking ability and admirable adaptation to very different ecological conditions. Recently, the mutton of Ujimqin sheep is widely recognized as natural green food in China. Thus, it is necessary to improve meat quality traits of Ujimqin sheep for developing mutton sheep industry. In this study, four hundred and twenty castrated male Ujimqin lambs which under the same feeding conditions were randomly selected as experimental samples. The A384T SNP was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and the effect of this SNP on meat quality traits and fatty acid content were analyzed. The aim of this study was to investigate the association between the A384T SNP and meat quality traits in Ujimqin sheep. The results showed that there were 3 different genotypes (TT, TA and AA) at the A384T SNP site in Ujimqin sheep population. The frequency of TA genotype was the highest (0.4714), and the frequency of AA genotype was the lowest (0.1595) in this experimental animal population. The T allele was the dominant allele in this population. The genotype frequency of the A384T SNP was consistent with Hardy-Weinberg equilibrium (P>0.05). The pH24 of individuals with TT genotype were significantly higher than those of TA and AA genotype (P<0.01). The drip loss of individuals with TT genotype were significantly higher than those of the TA and AA genotype (P<0.05). There were no significant differences among genotypes in other meat traits, including pH1, carcass weight, net meat weight, eye muscle area and drip loss (P>0.05). The contents of palmitic acid and stearic acid in muscle tissue of TT genotype were significantly lower than those of TA and AA genotype individuals (P<0.01). The contents of myristic acid in muscle tissue of TT genotype were significantly lower than those of TA and AA genotype individuals (P<0.05). There were no significant differences in the other fatty acid contents among 3 genotypes (P>0.05). These data showed that the A384T SNP in the exon 3 of the LPL gene was associated with meat quality traits of Ujimqin sheep, and could be an effective genetic marker for molecular breeding of Ujimqin sheep. These results provide scientific basis for genetic improvement of Ujimqin sheep.
[1] 曹玮娜, 任战军. 2012. 肉兔机体组织中脂肪酸检测方法的选择与组成分析[J]. 中国养兔杂志, (4): 13-18. (Cao W N, Ren Z J. 2012. Analysis of fatty acids in different tissue from meat rabbit[J]. Chinese Journal of Rabbit Farming, (4): 13-18.) [2] 郭艳青, 许尚忠, 孙宝忠,等. 2007. 牛LPL基因的遗传变异与肉品质性状的关联分析[J]. 农业生物技术学报, 15(5): 899-900. (Gou Y Q, Xu S Z, Sun B Z, et al.2007. Genetic variation of LPL gene and association analysis with meat quality traits in Bovine[J]. Journal of Agricultural Biotechnology, 15(5): 899-900.) [3] 金花, 宝力日尔敦. 2015. 自然放牧条件下乌珠穆沁羔羊肉营养品质[J]. 畜牧与饲料科学, (2): 17-19. (Jin H, Bao L. 2015. Nutritional quality of Ujimqin lamb under natural grazing conditions[J]. Animal Husbandry and Feed Science, (2): 17-19.) [4] 梁富武. 2010. 乌珠穆沁羊的选育攻关[J]. 中国畜牧业, (17): 38-39. (Liang F W. 2010. Breeding of Ujimqin sheep[J]. China Animal Industry, (17): 38-39.) [5] 刘国民, 徐晓静, 韩敏, 等. 2011. 无角道赛特羊与苏尼特羊、乌珠穆沁羊血液生化指标的比较研究[J]. 黑龙江畜牧兽医, (1): 57-58. (Liu G M, Xu X J, Han M, et al. 2011. Comparative study on blood biochemical indicators of Hornless Road Set sheep, Sunite sheep and Ujimqin sheep[J]. Heilongjiang Animal Science and veterinary Medicine, (1): 57-58.) [6] 刘莹莹, 李凤娜, 印遇龙, 等. 2015. 中外品种猪的肉质性状差异及其形成机制探讨[J]. 动物营养学报, 27(1): 8-14. (Liu Y Y, Li F N, Yin Y L, et al.2015. Meat quality traits differences between Chinese local and foreign pig breeds and a discussionon their formation mechanisms[J]. Chinese Journal of Animal Nutrition, 27(1): 8-14.) [7] 皮立, 胡凤祖, 星玉秀, 等. 2012. 青海欧拉羊肌肉脂肪酸组成的气相色谱-质谱分析[J]. 食品科学, 33(6): 190-193. (Pi L, Hu F Z, Xing Y X, et al.2012. GC-MS analysis of muscle fatty acid composition of Oula sheep living in Qinghai province[J]. Food Science, 33(6): 190-193.) [8] 乔永, 黄治国, 李齐发, 等. 2007. 绵羊肌肉LPL基因表达的发育性变化及其对肌内脂肪含量的影响[J]. 中国农业科学, 40(10): 2323-2330. (Qiao Y, Huang Z G, Li Q F, et al.2007. Developmental changes of the LPL mRNA expression and the effect on IMF content in sheep muscle[J]. Scientia Agricultura Sinica, 40(10): 2323-2330.) [9] 申正, 曹阳, 赵淑娟, 等. 2017. 美利奴羊与细毛羊杂交F1代LPL基因外显子3 A384T位点多态性与肉质性状的关联分析[J]. 黑龙江畜牧兽医, (11): 93-96. (Shen Z, Cao Y, Zhao S J, et al. 2017. Polymorphism of LPL #gene exon 3 A384T and its correlation with meat traits in hybrid F1 of merino sheep and fine-wool sheep[J]. Heilongjiang Animal Science And veterinary Medicine, (11): 93-96.) [10] 史新平, 陈燕, 徐玲, 等. 2018. 肉用西门塔尔牛与和牛杂交群体的肉品质分析[J]. 中国畜牧兽医, 45(4): 953-960. (Shi X P, Chen Y, Xu L, et al.2018. Analysis of beef simmental and Wagyu hybrid cattle on meat quality[J]. China Animal Husbandry & Veterinary Medicine, 45(4): 953-960.) [11] 汤晓艳, 周光宏, 徐幸莲. 2006. 大理石花纹、生理成熟度对牛肉品质的影响[J]. 食品科学, 27(12): 114-117. (Tang X Y, Zhou G H, Xu X L.2006. Study on effect of marbling and physiological maturity degree on meat quality of crossbred yellow cattle[J]. Food Science, 27(12): 114-117.) [12] 陶晓臣, 刘兴亮, 高爱琴, 等. 2012. 不同品种绵羊背最长肌PRKAG3和LPL基因的表达差异[J]. 中国草食动物科学, (z1): 224-227. (Tao X C, Liu X L, Gao A Q, et al. 2012. The differential expression of PRKAG3# and LPL# gene in longissimus muscle of different sheep breeds[J]. China Herbivores, (z1>): 224-227.) [13] 韦克林, 胡天龙, 李坤. 2012. 肌内脂肪、脂肪酸与猪肉肉质三者关系研究进展[J]. 中国畜牧兽医文摘, (11): 50-51. (Wei K L, Hu T L, Li K. 2012. Research progress on relationship between intramuscular fat, fatty acid and pig meat quality[J]. China Animal Husbandry & Veterinary Medicine, (11): 50-51.) [14] 张爱平, 彭方, 余方白, 等. 2018. 不同月龄湖羊及其杂种乳羔肉脂肪酸含量的研究[J]. 家畜生态学报, 39(3): 29-33. (Zhang A P, Peng F, Yu F B, et al.2018. Fatty acid content of different ages of Hu sheep and its hybrid lamb mutton[J]. Acta Ecologiae Animalis Domastici, 39(3): 29-33.) [15] 张冬梅, 梁图雅, 苏和, 等. 2017. 乌珠穆沁羊骨骼肌中脂肪酸的组成与相关基因表达量分析[J]. 中国食品学报, 17(6): 219-224. (Zhang D M, Liang T Y, Su he, et al.2017. The analysis of fatty acids composition and expression of related genes of skeletal muscle in Ujumqin sheep[J]. Journal of Chinese Institute of Food Science and Technology, 17(6): 219-224.) [16] 张秀兰, 杨新平, 刘芳, 等. 2012. 脂蛋白脂肪酶和动脉粥样硬化[J]. 中国药物与临床, 12(10): 1309-1311. (Zhang X L, Yang X P, Liu F, et al.Lipoprotein lipase and atherosclerosis[J]. Chinese Remedies & Clinics, 12(10): 1309-1311.) [17] 朱喜艳. 2010. 青海省各区域藏羊肉脂肪酸含量的对比分析[J]. 黑龙江畜牧兽医, (6): 106-108. (Zhu X Y. 2010. Comparative analysis of fatty acid content of Tibetan mutton in Qinghai province[J]. Heilongjiang Animal Science and Veterinary Medicine, (6): 106-108.) [18] 邹华锋, 文美英, 魏星华, 等. 2013. 生猪宰前不同静养时间和屠宰方式对背长肌肌肉pH值和滴水损失的影响[J]. 肉类工业, (5): 19-21. (Zou H F, Wen M Y, Wei X H, et al. 2013. Effects of different resting time before pig slaughtering and slaughtering methods on pH value and drip loss of porcine longissimus muscle[J]. Meat Industry, (5): 19-21.) [19] Bandi N, Gholizadeh M, Rahimi-Mianji G, et al.2017. Comparative study of gene structure in the upstream regulatory region of CDC10 and MYBPC1 genes in Iranian fat-tailed and nonfat-tailed sheep breeds[J]. Livestock Science,(6). [20] Emmerich J, Beg O U, Peterson J, et al.1992. Human lipoprotein lipase. Analysis of the catalytic triad by site-directed mutagenesis of Ser-132, Asp-156, and His-241[J]. Journal of Biological Chemistry, 267(6): 4161-4165. [21] Havel R J, Fielding C J, Olivecrona T, et al.1973. Cofactor activity of protein components of human very low density lipoproteins in the hydrolysis of triglycerides by lipoproteins lipase from different sources[J]. Biochemistry, 12(9): 1828. [22] Kimata M, Ishibashi T, Kamada T.2001. Studies on relationship between sensory evaluation and chemical composition in various breeds of pork[J]. Japanense Journal of Swine Science, 38(2): 45-51. [23] Muroya S, Ohnishi-Kameyama M, Oe M, et al.2007. Postmortem changes in bovine troponin T isoforms on two-dimensional electrophoretic gel analyzed using mass spectrometry and western blotting: The limited fragmentation into basic polypeptides[J]. Meat Science, 75(3): 506-514. [24] Rovadoscki G A, Pertile S F N, Alvarenga A B, et al.2018. Estimates of genomic heritability and genome-wide association study for fatty acids profile in Santa Inês sheep[J]. Bmc Genomics, 19(1): 375. [25] Wang W, Xue W, Jin B, et al.2013. Candidate gene expression affects intramuscular fat content and fatty acid composition in pigs[J]. Journal of Applied Genetics, 54(1): 113-118. [26] Yan W, Zhou H, Hu J, et al.2018. Variation in the FABP4 gene affects carcass and growth traits in sheep[J]. Meat Science, 145: 334-339. [27] Yu H, Waddell J N, Kuang S, et al.2018. Identification of genes directly responding to DLK1 signaling in Callipyge sheep[J]. BMC Genomics, 19(1): 283.
