title: Complete sequences of 3' end coding region for structural protein genes of turkey coronavirus.
abstract: Overlapping fragments of genomic RNA spanning 6963 nucleotides from 5' end of spike (S) protein gene to 3' end of nucleocapsid (N) protein gene of turkey coronavirus (TCoV) were amplified by reverse-transcription-polymerase chain reaction (RT-PCR). The primers were derived from the corresponding sequences of infectious bronchitis virus (IBV). The PCR products were cloned and sequenced and their nucleic acid structure and similarity to published sequences of other coronaviruses were analyzed. Sequencing and subsequent analysis revealed 9 open reading frames (ORFs) representing the entire S protein gene, tricistronic gene 3, membrane (M) protein gene, bicistronic gene 5, and N protein gene in the order of 5'-3'. The overall nucleic acid structures of these encoding regions of TCoV were very similar to the homologous regions of IBV. The consensus transcription-regulating sequence (TRS) of IBV, CT(T/G)AACAA, was highly conserved in TCoV genome at the levels of nucleotide sequence and location in regarding to the initiation codon of individual genes. Pair-wise comparison of gene 3, M gene, gene 5, or N gene sequences with their counterparts of IBV revealed high levels (82.1-92.0%) of similarity. Phylogenetic analysis based on the deduced amino acid sequences of S, M, or N protein demonstrated that TCoV was clustered within the same genomic lineage as the IBV strains while all the other mammalian coronaviruses were grouped into separate clusters corresponding to antigenic groups I or II. There were substantial differences of S protein sequence between TCoV and IBV with only 33.8-33.9% of similarity.
authors.affiliation: Department of Veterinary Pathobiology, Purdue University, ADDL, 406 South University Street, West Lafayette, Indiana 47907-2065, USA. tllin@purdue.edu
authors.forename: Tsang Long
authors.initials: TL
authors.lastname: Lin
authors.forename: Chien Chang
authors.initials: CC
authors.lastname: Loa
authors.forename: Ching Ching
authors.initials: CC
authors.lastname: Wu
mesh_terms: D000818:Animals; D001483:Base Sequence; D004752:Coronavirus, Turkey / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D004279:DNA, Viral / Q000032:analysis; D005814:Genes, Viral; D016679:Genome, Viral; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014422:Turkeys; D015678:Viral Structural Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D004279:DNA, Viral; D015678:Viral Structural Proteins