东串猪FUT2基因CDS扩增、序列分析及组织表达谱检测

Amplification,Sequence Analysis and Tissue Expression Detection of FUT2 Gene Coding Regions of Dongchuan Pigs

猪α-(1,2)岩藻糖转移酶2(FUT2)基因为鞘糖脂生物合成—球系列通路中的重要基因,可能在断奶仔猪抵抗大肠杆菌F18侵染过程中发挥着调控作用。为探究猪FUT2基因的序列结构及其生物学功能,试验采用PCR扩增得到地方猪品种东串猪FUT2基因的CDS全序列,进而预测和分析FUT2基因的蛋白质序列及其功能区域,同时对其在8头35日龄东串断奶仔猪11个组织中的表达水平进行检测与分析。结果显示,FUT2基因的CDS序列全长为1 023bp,共编码340个氨基酸,FUT2蛋白为脂溶性的亲水蛋白,蛋白结构不稳定,该蛋白存在1个跨膜螺旋结构,但不存在信号肽,表明FUT2蛋白为膜蛋白;FUT2蛋白存在2个N-糖基化位点(185和305位氨基酸),无O-糖基化位点,此外该蛋白还存在14个潜在的磷酸化位点,包括6个Ser、2个Thr和6个Tyr,对其功能区域进行分析发现,FUT2蛋白存在1个超级家族保守结构域:FUT1-FUT2-like(58-319位氨基酸);系统进化树结果显示,猪与牛的亲缘关系相对较近,与人、黑猩猩、大鼠和小鼠等亲缘关系相对较远;FUT2基因在东串断奶仔猪11个组织中均有表达,在消化道和免疫组织中表达水平较高。试验结果推测FUT2基因在断奶仔猪抵抗大肠杆菌F18中可能具有一定的作用,且可能是通过合成岩藻糖转移酶间接发挥其抵抗大肠杆菌F18的作用。

Porcine alpha（1,2）fucosyltransferase（FUT2）gene was importance in glycosphingolipid biosynthesis-globo series,potentially played a regulatory role during Escherichia coli（E.coli）F18infection process in weaned piglets.In order to explore sequence structure of porcine FUT2 gene and its biological function,this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR,forecasted and analyzed the protein sequences and functional regions of FUT2 gene,its expression level was detected in 11 tissues of 8Dongchuan weaned piglets in 35 days old at the meantime.The results showed that the CDS sequence of FUT2 gene was 1 023 bp,which encoded 340 amino acids.FUT2 protein was fat-soluble hydrophilic protein,which the structure was not stable,including a transmembrane helix structure,but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2protein included 2N-glycosylation sites（No.185 and No.305 amino acids）,without O-glycosylation sites,there were 14 potential phosphorylation sites,included 6Ser,2Thr and 6Tyr,analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains：FUT1-FUT2-like（58-319 amino acids）.The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close,but was distant from chimpanzee,human,mouse and rat.FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets,there were higher expression in digestive tract and immune tissues.The present results suggested that FUT2 gene might play a role to resistance to E.coli F18 in weaned piglets,and might indirectly against E.coli F18 through the synthesis of fucosyltransferase.