Cloning And Characterization Analysis On Structural Protein Gene Of Porcine Transmissible Gastroenteritis Virus

According to the published nucleotide sequence of structure protein gene of transmissible gastroenteritis virus (TGEV), three pair specific primers for S (spike glycoprotein)gene and three others for each of sM (small membrane protein),M(integral membrane protein) and N(nucleocapsid protein) genes of TGEV were designed and synthesized.These genes of TGEV strain TS were amplified by reverse-transcription-polymerase-chain-reaction(RT-PCR) method.Then the fragments of these genes were sequenced and analyzed ,and the sequence characterization of every gene was compaired with several published TGEV strains. The results as follows:Three fragments of 1262 bp,2368 bp and 1266 bp of strain TS S gene were obtained, respectively.The S gene of strain TS cDNA encompassed 4347 nucleotides (nt) and encoded a protein of 1449 amino acids with 34 potential sites for 7V-glycosylation,but only 32 sites in TGEV strains Purdue, TH-98 and NEB72-RT.The S gene of strain TS as well as strains Miller, FS722/70,TGEV H,96-1933,TFI is longer than that of strain Purdue,TH-98 and NEB72-RT 6 nt with 5'-ATGATA -3' in 1124?129 nucleotide sequence.The nucleotide sequence homology of S gene between strains TS and Miller,FS722/70,TFI,Purdue,96-1933,TGEV H ,TH-98, NEB72-RT and PRCV-HOL87 is 99.6 %, 98.9 %, 98.0 %, 46.9 %, 95.7 %, 99.3 %, 46.8 %, 46.9 % 29.0 % and putative amino acid identity is 99.1 %, 98.4 %, 97.7 % 97.6 %, 94.7 %, 98.6 % 97.0 %, 97.5 % , 96.7 %, respectively.Three fragments of 346 bp,932 bp,1217 bp as expected to the sM, M, N gene of strain TS acquired, respectively.The sM M N genes of strain TS are 248 bp,789 bp,1149 bp in length and encoded proteins of 82,262,382 amino acids, respectively. The sM gene of strains TS shared 95.2 %, 92.7 %, 90.2 % nucleotide homology and 95.9 %, 97.2 % 98.8 % putative amino acid that of Purdue,TFI,96-1933; M gene of strains TS shared 95.2 %, 98.0 % 99.6 % , 95.0 % nucleotide identity and 97.0 %, 97.3 % 98.5 % -. 93.5 % deduced amino acid that of strains Purdue,TFI,TGEV H,96-1933; The nucleotide sequence homology of N gene between strain TS and strains Purdue,TFI,FS722/70,Korea,TO14,TGEV H, 96-1933 are 98.1 %, 97.7 %, 99.0 % 98.3%, 99.2 %, 99.0 %, 95.9 % and putative amino acid homology are 97.9 %, 98.4 %, 99.0%, 97.7 %, 99.5 %, 66.2 %, 96.6 %, respectively.