Genotype determination and sequencing of F glycoprotein gene of Newcastle disease viruses in Taiwan

• Main Authors: Kao, Ying-Tai, 英泰
• Other Authors: Wang Ching-Ho
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/35189671517609937549

碩士 === 國立臺灣大學 === 獸醫學系 === 85 === Restriction site analysis and direct sequencing were applied to explore the variety of Newcastle disease viruses isolated from Taiwan. A 1,349 bp fragment of the F gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) with the primers, Fd3 and Fd5. PCR products were cleaved by three restriction endonucleases, Hinf I, BstO I and Rsa I and the positions of the restriction sites were mapped. Restriction site analysis showed that four patterns of restriction sites could be found in seven Taiwan isolates. The restriction sites of the chicken isolates from either before or during the 1995 outbreak were all the same, and the number of the restriction sites of Hinf I, BstO I and Rsa I were 4, 2 and 4, respectively. An additional restriction site of Hinf I was found in the owl isolate from the same outbreak, but the isolate from 1991 only had 3 restriction sites of Rsa I. The isolate from 1969 showed the variation most. The 1969 isolate was found 6 unique restriction sites. The number of the different restriction sites of Hinf I, BstO I and Rsa I were 1, 4 and 1, respectively. The F gene of the owl isolate was sequenced by RT-PCR and direct sequencing. A 1,624 bp sequence was obtained. The deduced amino acid sequence showed the character of virulent strains; the sequence of the cleavage site for the protease was 112R-R-Q-K-R-F117. According to the phylogenic analysis, the owl isolate was most close to the isolate from the same outbreak, TAIWAN/95.