山羊FTO基因克隆及其表达谱

Cloning and Expression Profiling of FTO Gene of Goat

本研究旨在阐明山羊FTO基因的表达特性,并分析其表达与肌内脂肪沉积的相关性。以简州大耳羊为试验动物,采用RT-PCR方法克隆FTO基因,利用实时荧光定量PCR和Western blotting技术检测其组织表达差异,同时检测该基因在不同发育阶段不同部位山羊肌肉组织中的表达水平,并与IMF含量进行相关分析。结果表明,山羊FTO基因CDS区为1 518bp,编码505个氨基酸,为无跨膜结构的非分泌蛋白。FTO mRNA在山羊的脂肪、脾和肺中表达水平较高（P〈0.01）,在背最长肌中表达最低;FTO蛋白在背最长肌和脾中表达较高（P〈0.01）,脂肪组织中表达次之。同时结果显示,FTO mRNA在24月龄山羊背最长肌和股二头肌中表达水平显著高于1-3和8-10月龄的表达水平（P〈0.05）。FTO mRNA表达量与背最长肌IMF含量呈显著负相关（P〈0.05）,与股二头肌及臂三头肌IMF含量呈不同程度的正相关。本研究指出,FTO基因表达与IMF含量存在相关性,推测可作为IMF沉积的候选基因。

The aim of this study was to clarify the expression characteristics of FTO gene and in- vestigate the correlation between FTO expression and intramuscular fat （IMF） content in mus- cles. The FTO gene was cloned from Jianzhou Daer goat by RT-PCR method. Quantitative Real- time PCR（qPCR） and Western blotting were used to measure the expression profiles of FTO gene in tissues, especially in various parts of muscle of goats at different developmental stages. The cor- relation analysis was performed between FTO gene and IMF content. The results showed that goat FTO gene was 1 518 bp in CDS length,encoding 505 amino acids. The FTO protein was pre- dicted to be non-secretory and lacking cross-membrane domain. The mRNA level of FTO was higher in adipose, spleen and lung （P〈0.01）, while lowest in longissimus dorsi;However, the protein level of FTO was higher in longissimus dorsi and spleen than that in adipose （P〈0.01）. The mRNA level of FTO was significantly higher in longissimus dorsi and biceps femoris of 24- month-old goats than that in 1 to 3-month-old and 8 to 10-month-old goats （P〈0. 05）. ThemRNA level of FTO was negatively correlated with IMF content of longissimus dorsi （P〈O. 05） but positively correlated with IMF content of biceps femoris and triceps brachii. In this study,we investigated a significant correlation between FTO expression and IMF,which indicates that FTO may serve as a candidate gene for IMF.