Cloning and Sequence Analysis of the Nucleocapsid Gene of a Variant Strain (793/B) of Avian Infectious Bronchitis Virus
Abstract: A pair of primers were designed and synthesized based onthe genomic sequences of the Nucleocapsid gene of IBV in Genbank. The gene encoding the nucleocapsid protein (N) was amplified by RT-PCR. Sequencing data showed that the complete gene encoding the nucleocapsid of IBV isolate (793/B) consisted of 1229 nucleotides. Sequence analysis showed that 88 point mutations were found in the N gene, and one nucleotide was deleted inform position 991. By comparison with 11 strains in GenBank, the sequence identity was 86.9％~91.4％, and the identity of the deduced amino acids was 75.8％~77.5％. The results showed that there were major variatons in the N gene of 793/B.