口蹄疫病毒非结构蛋白P3区的基因序列及分析

Nucleotide Sequence of Non-structural Protein P3 Coding Region of Foot-and-mouth Disease Virus

以口蹄疫Akesu/ 5 8分离株的 5 3代牛舌皮病料为材料 ,采用RT PCR法 ,扩增和克隆了两个约 1.5kb的DNA片段。核酸序列测得结果对接后 ,涵盖了全部P3区的基因序列。口蹄疫Akesu/ 5 8分离株基因组P3区的核酸序列共计 2 ,72 4nt,包括一个终止密码子TAA ,共编码 90 7个氨基酸 ;其中非结构蛋白 3A的基因是 45 9nt,编码 15 3个氨基酸 ;3个 3B(VPg)基因分别是 6 9、72和 72nt,氨基酸分别为 2 3、2 4和 2 4;3C是 6 39nt,2 13个氨基酸 ;3D是1,413nt ,471个氨基酸。各蛋白间由Glu/Gly(Ser)连接。序列比较显示 :3A的C端易变 。

Two 1.5kb DNA were amplified by reverse transcription and PCR(RT-PCR) from the epithelial tongue tissue of cattle infected with FMDV akesu/58 strain after 53 passages, and then cloned. A continuous 2,724 nucleotide sequence spanning the P3 coding region was obtained, including a ending codon TAA. 907 amino acids were encoded. 3A protein gene was composted of 459 nucleotides, encoding 153 amino acids. Three 3B(VPg) genes had 69,72 and 72 nucleotides and encoded 23,24 and 24 amino acids, respectively. 639 nucleotides and 213 amino acids were attributed to 3C and 1,413 nucleotides and 471 amino acids to 3D. All proteins were linked by cleavage sites Glu/Gly(Ser). In addition, the variate C terminal part of 3A protein has been identified by sequence alignment with other FMDV strains.