Ex-FABP作为鸡腹脂性状主要候选基因的研究

Study of Ex-FABP as a Main Candidate Gene on Abdominal Fat Traits in Chicken

细胞外脂肪酸结合蛋白(extracellular fatty acid-binding protein,Ex-FABP)基因是脂肪酸结合蛋白(fatty acid-binding protein,FABP)家族的另一成员,参与鸡的脂肪酸、肌纤维、骨骼等调控过程.利用PCR-SSCP(single strand conformation polymorphism)和DNA测序的方法,对不同品种的杂交鸡进行了Ex-FABP基因5'调控区部分序列的多态性分析,发现了3个单核苷酸多态性(single nucleotide polymorphisms,SNPs)位点.其中,此片段中的碱基C(-1000)的插入和碱基T→C(-1011)的突变,导致此处比野生型基因少了1个cap,多了1个Nkx-2、1个AhR/Ar和2个CF1等转录因子结合位点的产生.利用SAS软件对Ex-FABP基因5'调控区的SNPs与屠体性状的最小二乘分析,发现基因型BB(突变型)与腹脂重存在极显著相关(P<0.01).研究结果表明,细胞外脂肪酸结合蛋白(Ex-FABP)基因是影响脂肪沉积、控制腹脂性状的主要候选基因.

Extracellular fatty acid-binding protein (Ex-FABP) is another family member of fatty acid-binding protein, it regulates the metabolism of fatty acid, muscle fiber, bone and so on in chicken. Three single nucleotide polymorphisms (SNPs) were detected in 5' regulatory region of Ex-FABP gene using PCR-SSCP and DNA sequencing in crossbreed chickens. The changes of the bonding-sites of transcription factor are due to a single point mutation T -> C(-1011) and a C insertion mutation in genotype BB based on genotype AA, then results in a cap site lack, and increase four sites of a Nkx-2, a AhR/Ar and tow CF1. The relationship between SNPs and chicken meat traits was analyzed, the results showed that there was significant correlation (P < 0.01) between genotype BB mutant and abdominal fat weight. The results of this study indicated that Ex-FABP gene is the main candidate gene that regulates abdominal fat traits in chicken.