猪小脂肪细胞因子1（SMAF1）基因cDNA的克隆及表达谱分析

采用比较基因组学和RT-PCR方法，根据人和小鼠SMAF1基因的保守序列，设计简并引物，克隆了猪SMAF1基因的cDNA序列。所克隆片断全长256bp（GeneBank登录号 DQ191892），包括一个编码了81个氨基酸的完整编码区，该序列与人和小鼠的SMAF1基因的相似性分别为86%和78％，预测的氨基酸序列与人、小鼠、大鼠和牛的相似性分别为81％、67％、70%和84%。猪SMAF1基因在脂肪组织中高丰度表达，在4月龄瘦肉型猪（大白猪）脂肪组织中的表达量显著低于脂肪型猪（梅山猪）（P＜0.05）。本研究结果表明，猪SMAF1基因可能具有和其它物种SMAF1基因相似的功能，推测其在脂肪细胞发生和/或脂肪细胞功能中具有重要的调控作用。

Cloning and Expression Analysis of Porcine Small Adipocyte Factor 1(SMAF1) Gene

The cDNA of porcine SMAF1 gene was amplified by RT-PCR with degenerate primers designed according to the conserved sequences between human and mouse SMAF1 genes. The cDNA (GenBank accession No.DQ191892) containing a complete coding region was 256 bp in length, sharing 86% and 78% identity with those of human and mouse, respectively. The comparison of the deduced amino acids sequence of porcine SMAF1 with those of human, mouse, cattle, and rat showed that the amino acids homology were 81%, 67%, 84% and 70%, respectively. The results of semi-quantitative RT-PCR showed that porcine SMAF1 gene was expressed abundantly in adipose tissue, and at significantly lower level in lean type pigs (Large White pigs) than that in lard type pigs (Meishan pigs) at the age of four months (P <0.05). The results suggest that porcine SMAF1 gene may have similar functions as in other species, that is, it may regulate the adipogenesis and/or adipocyte function.