麻疹病毒血凝素基因助融合(Fusion helper)活性区的定位  

LOCALIZATION OF THE FUSION HELPER FUNCTION REGION OF MEASLES VIRUS HEMMAGGLUTININ GENE

作　　者：杨克俭[1] 阮力[1] 孙朝辉 陆柔剑[1] 朱既明[1] 

机构地区：[1]中国预防医学科学院病毒学研究所

出　　处：《病毒学报》1997年第1期13-18,共6页Chinese Journal of Virology

摘　　要：在利用ＰＣＲ方法克隆麻疹病毒Ｌ４株血凝素（ＨＡ）基因的过程中，获得了一个助融合活性丢失的Ｂ号克隆。其氨基酸序列与具有助融合活性的Ａ号克隆相比，有４个位点不同，分别位于９６、１１７、１４８及５４３位。通过基因间部分序列的交换及定点回复突变，获得了相应位点的突变体。对这些突变体的助融合活性研究发现，１１７、１４８及５４３位氨基酸的改变不影响助融合活性，而当９６位脯氨酸定点回复突变为亮氨酸后，Ｂ克隆血凝素蛋白获得了助融合活性。提示ＨＡ蛋白９６位氨基酸是影响助融合活性的一个重要氨基酸。A hemmagglutinin gene HA(B) of measles virus which has lost the function of fusion helper was cloned from L4 strain of measles virus by PCR.Sequence analysis showed that four amino acids were changed at position 96、117、148 and 543 in the clone HA(B) when compared with that of the clone HA(A) which possesses good fusion helper function.A series of mutated HA genes were obtained by exchanging the corresponding fragments of these two different clones and by site-directed mutation.It was found that changes of amino acids at the positions 117、148 and 543 did not affect the fusion helper function,but the fusion helper function of HA(B) gene could be restored when its proline at 96 position was mutated back to leucine.The results indicate that the amino acid located at position 96 of measles virus HA is closely related with its fusion helper function.

关 键 词：麻疹病毒 血凝素 基因 助融合活性 

分 类 号：R373.11[医药卫生—病原生物学]