猪源新城疫病毒SP13株的F基因克隆及序列分析

Cloning and sequencing of fusion gene of newcastle disease virus SP13 from swine

采用RT-PCR方法对猪源新城疫病毒(NDV)SP13株的F基因进行了扩增与克隆,并测定出F基因的核苷酸全序列,推导出氨基酸序列.F基因全长为1662 bp,单一的开放阅读框,编码553个氨基酸的长肽,裂解位点的氨基酸序列为112G-R-Q-G-R-L117,与弱毒株在这一区域的序列(112G-R/K-Q-G/S-R-L117)相符;F蛋白有6个潜在的糖基化位点和13个Cys残基位点,其疏水构型有3个强疏水区.通过同源率、系统发育、致病性、疏水性和抗原性等比较分析的结果表明,SP13与LaSota、Clone 30株不但同源性达到99.9%,而且在致病性、疏水性和抗原性等方面也极为相似.

Fusion gene of newcastle disease virus （NDV） SP13 Strain from swine was amplified by reverse transcriptase-polymerase chain reaction （RT-PCR） and cloned into the pMD 18-T simple vector. The sequence of the cDNA was obtained by sequencing technique with their amino acid sequence being deduced. The results indicated that F gene is 1662 bp in length and has a single opening read frame, which codes for polypeptide of 553 amino acid. The amino acid sequence of cleavage region was ^112 G - R - Q - G - R - L^112 which is the same as all virulent strains. There are 6 potential asparagine-linked glycosylation sites, 13 cysteine residues and 3 highly hydrophobic domains in F protein. Nucleotide sequences and deduced amino acids sequence analysis showed that homologous rate of SP13, LaSota and Clone 30 is 99.9%, and there are high similarities in pathogenicity, hydrophobicity and antigencity.