FABP4基因在阿勒泰羊尾脂沉积与代谢模型中的表达变化规律

Analysis of FABP4 expression pattern in rump fat deposition and metabolism of Altay sheep

FABP4(Fatty acid binding protein 4)参与细胞内脂肪酸的转运和脂肪酸代谢,是当前研究动物脂肪沉积与代谢的热门候选基因。为了研究FABP4基因在绵羊尾脂沉积与代谢中的作用,文章采用生物信息学方法分析了FABP4氨基酸序列在各物种中的保守性;利用半定量RT-PCR方法检测了该基因在阿勒泰羊主要组织中的表达;采用饥饿法成功建立了模拟阿勒泰羊尾脂沉积与代谢的动物模型,利用q PCR和i TRAQ(isobaric tags for relative and absolute quantitation)技术同时验证FABP4基因m RNA和蛋白在阿勒泰羊非饥饿组与饥饿组尾脂中的表达变化。序列分析结果表明,绵羊FABP4氨基酸序列在物种间高度保守,提示FABP4基因可能由于其重要的生物功能而在进化中表现出其物种的保守性。组织表达谱结果显示,FABP4 m RNA在阿勒泰羊肠脂与尾脂中均高丰度表达,暗示FABP4基因可能在脂肪中行驶着重要的生理生化功能。q PCR与i TRAQ结果显示,FABP4 m RNA与蛋白在两种极端条件下尾脂中的表达差异均不显著(P>0.05),表明FABP4基因可能不是绵羊尾脂沉积与代谢两种极端差异表型的决定基因。以上研究结果为进一步研究FABP4基因在绵羊尾脂中的生物功能奠定了基础。

FABP4 （Fatty acid binding protein 4） is a hot candidate gene in fat deposition and lipid metabolism and participates in the transport and metabolism of intracellular free fatty acids. We aim to study the role of FABP4 in fat deposition and metabolism of the rump fat in Altay sheep. In this study, bioinformatics method was used to analyzethe protein sequence homology among 10 species, and RT-PCR was employed to detect FABP4 tissue profiling of Altay sheep. An animal mode/ simulating the rump fat deposition and metabolism of Altay sheep was established by continuous starvation, and qPCR and iTRAQ （isobaric tags for relative and absolute quantitation） were used to detecte FABP4 mRNA and protein expression changes in the control and continuous starvation groups, respectively. Sequence analysis showed that FABP4 protein sequence is highly conserved among species, suggesting an important biological function during evolution for FABP4. The RT-PCR result confirmed that FABP4 mRNA was highly expressed in intestinal and rump fat, suggesting that FABP4 plays an important physiological role in fat tissues. We did not find significant differences in FABP4 mRNA and protein between control and continuous starvation groups （P〉0.05）, which indicates that FABP4 may not be the key gene in fat deposition and metabolism in Altay sheep.The results above lay a foundation for further studies of FABP4 in rump or tail fat.