Avian Infectious Bronchitis Virus S1 Gene Rt-pcr, Rt-nested Pcr Amplification And Sequence Analysis Of,

RT-PCR and RT-NPCR was employed to amplify 7 strain IBV (M41, Ma5, SAIB4, SAIB ~ SAIB w~, SAIB6, SAIB 9) , including two standard stains(M4 1, Ma5) and 5 strain isolates (SAIB4, SAIB 14, SAIB wj, SAIB6, SAIB9) . And for the first time, the sequence analysis of three IBV isolates from Sichuan Province in China had been done. Two pairs of primer were designed referring to the S glycoprotein (including Si and S2 glycoprotein) gene sequence of IBV M4, strain published in Genbank (Accession number: M21883). A specific fragment about 1.72kb was produced by RT-PCR from five stains (M41, Ma5, SAIB4, SAIB,4 and SAIBwj) respectively, while no band from the rest two strains (SAIB6 and SAIB9). Then a band about 1.62kb, was amplified by RT-NPCR with the inside primer from all of the 7 strains. It is shown that RT-NPCR is more sensitive than RT-PCR. The RI-PeR product of three isolates (SAIB4, SAIB ~ and SAIBw1) was cloned and sequenced. The result shows that, the coding region is 1611 bp in size, coding a 1 8-amino signal-peptide and a 519-amino mat-peptide. All of the three gene sequences have been accessed by Genbank (Accession number: SAIB4 is bankit 404421, 5MB ,~ bankit 404417, and SAIB wj bankit 404422). Comparison of the Si gene sequences of the three IBV isolates with IBV M~ strain, the nucleotide homology of SAIB ,4,SAIB4 and SAIBw~ is respectively 95.10%, 79.24% and 80.45%, and the correspondingly amino-acid homology equals to 91.44%, 75.6i%and 76.16%.