摘要
采用RT-PCR、PCR-RFLP及测序技术,对山猪等背最长肌(LD)的品质及PPARγ2基因表达量和第一启动子Bsr1位点多态性进行研究.结果表明,LD上PPARγ2基因表达量较低,且与肌内脂肪(IMF)呈弱相关(R=0.22).对PPARγ2 Bsr1位点多态性研究发现,该位点可产生G/A突变,形成b、Bb和B型3种基因型.山猪LD PPARγ2 Bsr1位点包含3种基因型,二元杂交后b型比例下降,三元杂交会出现b型缺失.同时发现,长白和大约克LD b型不表达,长白猪仅有B型,而申农1号除B型外Bb型高表达,提示瘦肉猪定向选育过程中可能会使b型逐渐丢失或表达关闭,从而不利于脂肪细胞的增生.以PPARγ2基因型为主效因素与肉质性状拟合建立GLM模型,不同基因型间猪LD剪切力和IMF存在显著差异(P<0.05).b型的高表达有利于脂肪细胞分化和增生,故可维系较高的IMF和较好的肌肉嫩度,提示其可作为优质肉的目标基因.
Longissimus dorsi （LD） in swine （7 breeds）, was used to study PPART2 gene and its Bsrl locus （ located in PPART2 promoter 1 ）polymorphism with meat quality traits via RT-PCR,PCR-RFLP and sequencing technology. The result showed that the expression of PPART2 was low in swine LD. Its correlation with intramuscular fat was weak（R=0.22）. It was also found that the base G in wild type b（CCAGT）was replaced by A. b type of Bsrl locus would be changed to B type （CCAAT）thus it formed b,Bb and B type. Shanzhu LD had 3 genotypes,while its crossbreds had a low frequency of b type or even no b type. We also noticed that there was a high frequency of Bb type expressed in Shennong 1 and no b type in Landrace and Yorkshire. GLM model was used to analyze the association of genotypes（as a major factor）with meat quality traits. It was indicated that genotypes of PPART2 Bsrl locus were correlated with the shear force of meat and intramuscular fat, significantly （ P 〈 0. 05 ）. This suggested that the high expression of b type contributed to adipose differentiation, deposition and appropriate for meat tenderness. It also means that PPART2 gene can be the meat target gene.
出处
《南京师大学报（自然科学版）》
CAS
CSCD
北大核心
2013年第3期81-86,共6页
Journal of Nanjing Normal University(Natural Science Edition)
基金
江苏省农业科技创新基金(CX(11)1301)
