Epidemiological Surveillance: Genetic Diversity of Rotavirus Group A in the Pearl River Delta, Guangdong, China in 2019

Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals aged 28 days–85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA.Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0–1 year,and RVA is the key pathogen circulating in patients 6–10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains.Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development.

Architecture and biogenesis of plus-strand RNA virus replication factories

Plus-strand RNA virus replication occurs in tight association with cytoplasmic host cell membranes. Both, viral and cellular factors cooperatively generate distinct organelle-like structures, designated viral replication factories. This compartmentalization allows coordination of the different steps of the viral replication cycle, highly efficient genome replication and protection of the viral RNA from cellular defense mechanisms. Electron tomography studies conducted during the last couple of years revealed the three dimensional structure of numerous plus-strand RNA virus replication compartments and highlight morphological analogies between different virus families. Based on the morphology of virusinduced membrane rearrangements, we propose two separate subclasses: the invaginated vesicle/spherule type and the double membrane vesicle type. This review discusses common themes and distinct differences in the architecture of plus-strand RNA virus-induced membrane alterations and summarizes recent progress that has been made in understanding the complex interplay between viral and co-opted cellular factors in biogenesis and maintenance of plus-strand RNA virus replication factories.

Construction of Recombinant Pseudorabies Virus Expressing Canine Distemper Virus H Gene and Analysis on Its Biological Characters

[Objective] The aim was to construct a recombinant pseudorabies virus expressing canine distemper virus H gene and investigate its biological characters.[Method] H gene of canine distemper virus（CDV）strain Onderstepoort was produced by RT-PCR,inserted into pcDNA3.1（＋）vector to construct a expression cassette,which was then subcloned into transfer vector p8AA,prior to the insertion of LacZ expression cassette.The resulting new transfer vector was named as p8AAZH.Subsequently,p8AAZH was co-transfected with the genome of pseudorabies virus（PRV）Bartha-K61 into BHK-21 cells to enable gene recombination and virus package,and the virus solution was collected as cytopathic effect occurring.A series of procedures including blue plaque purification,PCR identification,observation under electron microscope and Western blot were carried out to screen the recombinant pseudorabies virus and identify the protein expression of target gene.Meanwhile,growth curve of the recombinant virus was determined in BHK-21 cells.[Result] The H gene had been inserted into the genome of Bartha-K61 strain,and RPRV-H was the same as Bartha-K61 in the one-step growth curve and cytopathic effect in BHK-21 cells.[Conclusion] The recombinant pseudorabies virus was constructed,and the insertion of H gene did not influence proliferation of recombinant virus,which laid a foundation for development of recombinant canine distemper virus vaccine.

Turnip mosaic virus pathogenesis and host resistance mechanisms in Brassica

Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the host responses involved in disease development in cruciferous crops.TuMV displays great versatility in viral pathogenesis,especially in its replication and intercellular movement.Moreover,in the coevolutionary arms races between TuMV and its hosts,the virus has evolved to co-opt host factors to facilitate its infection and counter host defense responses.This review mainly focuses on recent advances in understanding the viral factors that contribute to the TuMV infection cycle and the host resistance mechanism in Brassica.Finally,we propose some future research directions on TuMV pathogenesis and control strategies to design durable TuMV-resistant Brassica crops.

Partial Fusion (F) Gene Analysis of Newcastle Disease Virus Detected in Pakistan during 2021-2022

Newcastle disease (ND) virus is a leading threat to commercial and domestic poultry in Pakistan. The virus infects and constitutes irreversible impairment to the nervous system, damages the respiratory system, and marks severe gastrointestinal lesions leading to heavy mortality in short-living birds and substantial losses in layers and breeders. The continuous emergence and evolution of the virus made it inclined to evade the humoral response and indirectly the circumvention of artificial active immunization. Newcastle disease is caused by the orthoavula genus of the paramyxoviridae family and has shown high genetic diversity even in their genotypes while information regarding enzootic trends of the virus is scanty in Pakistan. A total of 40 tracheal samples of NDV were collected from different commercial broiler farms and 11 isolates of NDV were identified. In the current study, we determined the genetic diversity of the Newcastle disease virus based on the partial sequencing of the fusion protein gene available in the NCBI database. Genetic analysis showed that seven isolates belonged to class I genotype VII and four belonged to class II genotype II. Interestingly, two isolates had epidemiological connections with vaccine-like class II genotype II. Our findings, concerning the recent outbreaks of class I genotype VII and class II genotype II of NDV in vaccinated commercial flocks, suggest possible potential partial mutations in the fusion protein gene. Genetic diversity and formation of the new cleavage site in an important neutralizing protein of wild strain are linked with the potency of artificial active immunization and a major cause of vaccine failure.

Cloning and Sequence Analysis of HN and F Protein Genes from a Strain of Goose Paramyxovirus

[ Objective] The study was to clone HN and F genes from GX1 strain of goose paramyxovirus and analyze their sequences. [ Method] According to the full nucleotide sequence of GPV-SF02 strain of goose paramyxovirus, two pairs of pdmers were designed to amplify the HN and F genes from GX1 strain of goose paramyxovirus isolated from diseased goose in Guangxi Zhuang Autonomous Region; the amplified products were ligated into pMD18-T vector and sequenced. [ Result ] HN and F genes of this strain tested were 1 716 and 1 662 bp in full nucleotide length, respectively; both showed the homologues of about 97.3% with GPV- SF02 strain, of 80.3% -97.5% with strains LaSota, F48E9 and JS, of just 84.8% with Miyadera strain. [ Conclusion] The results show that isolated strain BX1 matches to virulent APMV-1 strain, belonging to genotype Ⅶ of APMV-1 strain.

Characterization of hepatitis B virus X gene quasispecies complexity in mono-infection and hepatitis delta virus superinfection

Hepatitis delta virus(HDV) seems to strongly suppress hepatitis B virus(HBV)replication, although little is known about the mechanism of this interaction. Both these viruses show a dynamic distribution of mutants, resulting in viral quasispecies. Next-generation sequencing is a viable approach for analyzing the composition of these mutant spectra. As the regulatory hepatitis B X protein(HBx) is essential for HBV replication, determination of HBV X gene(HBX)quasispecies complexity in HBV/HDV infection compared to HBV monoinfection may provide information on the interactions between these two viruses.AIM To compare HBV quasispecies complexity in the HBX 5' region between chronic hepatitis delta(CHD) and chronic HBV mono-infected patients.METHODS Twenty-four untreated patients were included: 7/24(29.2%) with HBeAgnegative chronic HBV infection(CI, previously termed inactive carriers), 8/24(33.3%) with HBeAg-negative chronic hepatitis B(CHB) and 9/24(37.5%) with CHD. A serum sample from each patient was first tested for HBV DNA levels.The HBX 5' region [nucleotides(nt) 1255-1611] was then PCR-amplified for subsequent next-generation sequencing(MiSeq, Illumina, United States). HBV quasispecies complexity in the region analyzed was evaluated using incidencebased indices(number of haplotypes and number of mutations), abundancebased indices(Hill numbers of order 1 and 2), and functional indices(mutation frequency and nucleotide diversity). We also evaluated the pattern of nucleotide changes to investigate which of them could be the cause of the quasispecies complexity.RESULTS CHB patients showed higher median HBV-DNA levels [5.4 logIU/mL,interquartile range(IQR) 3.5-7.9] than CHD(3.4 logIU/mL, IQR 3-7.6)(P = n.s.)or CI(3.2 logIU/mL, IQR 2.3-3.5)(P < 0.01) patients. The incidence and abundance indices indicated that HBV quasispecies complexity was significantly greater in CI than CHB. A similar trend was observed in CHD patients, although only Hill numbers of order 2 showed statistically significant differences(CHB2.81, IQR 1.11-4.57 vs CHD 8.87, 6.56-11.18, P = 0.038). There were no significant differences in the functional indices, but CI and CHD patients also showed a trend towards greater complexity than CHB. No differences were found for any HBV quasispecies complexity indices between CHD and CI patients. G-to-A and C-to-T nucleotide changes, characteristic of APOBEC3 G, were higher in CHD and CI than in CHB in genotype A haplotypes, but not in genotype D. The proportion of nt G-to-A vs A-to-G changes and C-to-T vs T-to-C changes in genotype A and D haplotypes in CHD patients showed no significant differences. In CHB and CI the results of these comparisons were dependent on HBV genotype.CONCLUSION The lower-replication CHD and CI groups show a trend to higher quasispecies complexity than the higher-replication CHB group. The mechanisms associated with this greater complexity require elucidation.

Effect of hepatitis C virus infection on expression of several cancer-associated gene products in hepatocellular carcinoma

AIM To study hepatocarcinogenesis of hepatitis C virus (HCV). METHODS Expression of HCV antigens (CP10, NS3 and NS5) and several cancer associated gene products (ras p21, c myc, c erbB 2, mutated p53 and p16 protein) in the tissues of hepatocellular carcinoma (HCC, n =46) and its surrounding liver tissue were studied by the ABC (avidin biotin complex) immunohistochemical method. The effect of HCV infection on expression of those gene products in HCC was analyzed by comparing HCV antigen positive group with HCV antigen negative group. RESULTS Positive immunostaining with one, two or three HCV antigens was found in 20 (43 5%) cases, with either of two or three HCV antigens in 16 (34 8%) cases, and with three HCV antigens in 9 (19 6%) cases. Deletion rate of p16 protein expression in HCC with positive HCV antigen (80%, 16/20) was significantly higher than that in HCC with negative HCV antigen. Whereas no significant difference of the other gene product expression was observed between the two groups. CONCLUSION HCV appears related to about one third of cases of HCC in Chongqing, the southwest of China, and it may be involved in hepatocarcinogenesis by inhibiting the function of p16 gene, which acts as a negative regulator of cell cycle.

Biological impact of hepatitis B virus X-hepatitis C virus core fusion gene on human hepatocytes

AIM： To investigate the biological impact of hepatitis B virus X- hepatitis C virus core （HBV X-HCV C） fusion gene on hepatoma cells.METHODS： The recombinant adenoviruses Ad- XC, Ad-X and Ad-C expressing HBV X-HCV C fusion gene, HBVX gene and HCV C gene were constructed, respectively. Hepatoma cells were infected with different recombinant adenoviruses. MTT, colony- forming experiment, FCM, TUNEL assay were performed to observe the biological impact of the HBV X-HCV C fusion aene on liver cells.RESULTS： MTT showed that the Ad-XC group cells grew faster than the other group cells. Colony-forming experiment showed that the colony-forming rate for the Ad-XC group cells was significantly higher than that for the other group cells. FCM analysis showed that Ad-XC/Ad-X/Ad-C infection enhanced the progression of G1→S phase in the HepG2 cell cycle. The apoptosis index of the Ad-XC, Ad-X, Ad-C group cells was significantly lower than that of the AdO and control group cells. Semi-quantitative RT-PCR showed that the expression level of c-myc was the highest in Ad- XC infected cells. Tumor formation was found at the injected site of mice inoculated with Ad-XC-infected LO2 cells, but not in control mice.CONCLUSION： Ad-XC, Ad-X and Ad-C facilitate the proliferation activity of HepG2 cells and inhibit their apoptosis in vitro. The effect of Ad-XC is significantly stronger than that of Ad-X and Ad-C. Up-regulation of c-myc may be one of the mechanisms underlying the synergism of HBVX and HCV C genes on hepatocarcinogenesis in athymic nude mice.

Characteristics and advantages of adeno-associated virus vector-mediated gene therapy for neurodegenerative diseases

Common neurodegenerative diseases of the central nervous system are characterized by progressive damage to the function of neurons, even leading to the permanent loss of function. Gene therapy via gene replacement or gene correction provides the potential for transformative therapies to delay or possibly stop further progression of the neurodegenerative disease in affected patients. Adeno-associated virus has been the vector of choice in recent clinical trials of therapies for neurodegenerative diseases due to its safety and efficiency in mediating gene transfer to the central nervous system. This review aims to discuss and summarize the progress and clinical applications of adeno-associated virus in neurodegenerative disease in central nervous system. Results from some clinical trials and successful cases of central neurodegenerative diseases deserve further study and exploration.

Pathogenesis of occult chronic hepatitis B virus infection

Occult hepatitis B infection(OBI) is characterized by hepatitis B virus(HBV) DNA in serum in the absence of hepatitis B surface antigen(HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns.Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays;but more frequently it is due to a strong suppression of viral replication and gene expression.OBI is an entity with world-wide diffusion.The failure to detect HBsAg,despite the persistence of the viral DNA,is due in most cases to the strong suppression of viral replication and gene expression that characterizes this"occult"HBV infection;although the mechanisms responsible for suppression of HBV are not well understood.The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection.Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.

Cloning and Phylogenetic Analysis of NS1 Genes from Different Isolates of H9N2 Subtype Duck Influenza Virus

[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007（H9N2） （A3 for short）, A/Duck/FJ/301/2007 （H9N2） （C1 for short）, A/Duck/NH/306/2007（H9N2） （ D6 for short）, A/duck/SS/402/2007（H9N2） （ E2 for short）, and a strain named A/duck/ZC/2007（H9N2） （L1 for short） from a muscovy duck died of avian influenza virus （AIV）, were used for NSl gene cloning and sequencing. Subsequently, the obtained NSl gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NSl genes of the four AIV strains A3, C1, 136 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NSl gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 （chicken, 2003）. By comparison with the NS1 gene sequences of L1, AF523514 （duck）, AY664743 （chicken） and EF155262.1 （quail） using DNAstar, A3, C1, D6 and E.2 presented nucleotide variations at site 21 （ R→Q）, 70, 71 （ KE→EG）, 86 （ A→S）, 124 （V→M） and 225 （ S→N）, and amino acid variations at site 21,70, 71 and 86 in dsRNA- dependent protein kinase （PKR） binding domain of NSl gene, which induced the evident variations of antigenic determinant and surface proba- bility plot of NS1 protein. [ Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity.

A MADS-box gene is involved in soybean resistance to multiple Soybean mosaic virus strains

Soybean mosaic virus(SMV)is a member of the genus Potyvirus that extensively impairs global soybean production.The full-length coding sequence of the MADS-box transcription factor Gm CAL was cloned from the SMV-resistant soybean cultivar Kefeng 1.SMV-induced expression analysis indicated that Gm CAL responded quickly to SMV-SC8 infection in Kefeng 1 but not in NN1138-2.Gm CAL was expressed at high levels in flowers and pods but at lower levels in leaves.The gene was localized to the nucleus by subcellular localization assay.Virus-induced gene silencing did not increase the accumulation of SMV in Gm CAL-silenced Kefeng 1 plants(with silencing efficiency~80%)after SC8 inoculation.Gm CAL-silencing plants still conferred resistance to SC8 that might be owing to incomplete silencing of genes with lower expression.SMV content decreased significantly in Gm CAL-overexpressing NN1138-2 plants after SMVSC3,SMV-SC7,and SMV-SC8 inoculation in comparison with a vector control,showing that overexpression of Gm CAL conferred broad-spectrum resistance to multiple SMV strains.These results confirm that Gm CAL,a key regulator but not a specific SC8 resistance gene(Rsc8),is a positive regulatory transcription factor involved in soybean resistance to SMV.

Genetic Diversity of Chinese Soybean mosaic virus Strains and Their Relationships with Other Plant Potyviruses Based on P3 Gene Sequences

Soybean mosaic virus （SMV）, a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide （NT） sequence identities and 95.1-100% amino acid （AA） sequence identities. The P3 coding regions of the 16 SMV isolates share high identities （92.4-98.9% NT and 96.0-100% AA） with the reported Korean isolates, followed by the USA isolates （88.5-97.9% NT and 91.4-98.6% AA）, and share low identities （80.5-85.2% NT and 82.1-84.7% AA） with the reported HZ 1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus （WMV）, with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable.

Lentivirus carrying the Atoh1 gene infects normal rat cochlea

Lentivirus carrying the Atohl gene can infect Corti＇s organ and express a hair-like cell surface marker in the supporting cell area. However, expression of the gene carried by adenovirus is instantaneous, which undoubtedly limits its clinical application. Lentivirus acts as a carrier that can stably and continuously express genes. In this study, the cochlear structure and hearing level were not affected, and Atohl gene carried by lentivirus promoted the production of hair-like cells in the cochlear supporting cell area. This led to expression of the hair-like cell surface marker myosin 7a 30 days after lentivirus carrying Atohl was microinjected into the cochlear round window of rats.

Molecular Characterization of the Duck Enteritis Virus UL4 Gene

Duck enteritis virus(DEV) is a herpesvirus that causes an acute,contagious and fatal disease. In the present article,the DEV UL4 gene was cloned and sequenced from a vaccine virus. A degenerate oligonucleotide primer for the consensus site of herpesvirus UL3 gene and a specific primer located in UL5 were used in the polymerase chain reaction(PCR) to amplify a DNA product 2 086 bp in size. DNA sequence analysis revealed that a 714 bp open reading frame(ORF) of DEV encoding a 237 amino acid polypeptide is homologous to the family of herpesvirus UL4 proteins and therefore has been characterized as a DEV UL4 gene. Alignment of the DEV UL4 protein sequence with those of other alphaherpesviruses showed that 10 amino acid residues are completely conserved. Phylogenetic tree analysis showed that the seventeen alphaherpesviruses viruses analyzed were classified into four large groups,and the duck enteritis virus branched separately,closely related to the Mardiviruses group comprising Gallid herpesvirus 2(GaHV-2) ,Gallid herpesvirus 3(GaHV-3) and Meleagrid herpesvirus 1(MeHV-1) . The present study showed that the evolutionary relationship of the UL4 protein could be used for classification of alphaherpesviruses.

An armed oncolytic adenovirus system,ZD55-gene,demonstrating potent antitumoral efficacy

ONYX-015 is an attractive therapeutic adenovirus for cancer because it can selectively replicate in tumor cells and kill them. To date, clinical trials of this adenovirus have demonstrated marked safety but not potent enough when it was used alone. In this paper, we put forward a novel concept of Gene-ViroTherapy strategy and in this way, we constructed an armed therapeutic oncolytic adenovirus system, ZD55-gene, which is not only deleted of ElB 55-kD gene similar to ONYX-015, but also armed with foreign antitumor gene. ZD55-gene exhibited similar cytopathic effects and replication kinetics to that of ONYX-015 in vitro. Importantly, the carried gene is expressed and the expression level can increase with the replication of virus. Consequently, a significant antitumoral efficacy was observed when ZD55-CD/5-FU was used as an example in nude mice with subcutaneous human SW620 colon cancer. Our data demonstrated that ZD55-gene, which utilizing the Gene-ViroTherapy strategy, is more efficacious than each individual component in vivo.

Transgene expression and differentiation of baculovirus-transduced adipose-derived stem cells from dystrophin-utrophin double knock-out mouse

In this study, recombinant baculovirus carrying the microdystrophin and β-catenin genes was used to infect adipose-derived stem cells from a dystrophin-utrophin double knock-out mouse. Results showed that, after baculovirus transgene infection, microdystrophin and β-catenin genes were effectively expressed in adipose-derived stem cells from the dystrophin-utrophin double knock-out mouse. Furthermore, this transgenic expression promoted adipose-derived stem cell differentiation into muscle cells, but inhibited adipogenic differentiation. In addition, protein expression related to the microdystrophin and Wnt/β-catenin signaling pathway was upregulated. Our experimental findings indicate that baculovirus can successfully deliver the microdystrophin and β-catenin genes into adipose-derived stem cells, and the microdystrophin and Wnt/β-catenin signaling pathway plays an important role in myogenesis of adipose-derived stem cells in the dystrophin-utrophin double knock-out mouse.

Genetic Variation Analysis of 3D Gene and Molecular Detection of Porcine Kobuvirus in 2013-2014

[Objective] This study aimed to investigate the prevalence and variation of porcine kobuvirus （PKV） in suckling piglets in China. [Method] In 2013-2014, 224 feces samples from suckling piglets with diarrhea in 27 pig farms of five provinces in China were collected to detect 3D genes of PKV with RT-PCR method; the sequences and genetic variation of 29 PKV 3D genes were analyzed. [Result] Total positive rate of PKV in feces samples from suckling piglets with diarrhea was 65.18% （146/224）; total positive rate of PKV in pig farms was 85,2% （23/27）; nucleotide sequences and the deduced amino acid sequences of 29 PKV 3D genes shared 87.0%-100% and 92.7%-100% homologies with six PKV-related 3D sequences, respectively. [Conclusion] PKV infection is prevalent in suckling piglets in China; PKV 3D genes exhibit high diversity.

Cloning and sequence analysis of E2 gene of bovine viral diarrhea virus HB-DCZ strain in Hebei province of China

The objective of this paper was to analyze the E2 genetic characterization of HB-DCZ strain of Bovine viral diaxrhca Virus （BVDV） which wcrc amplified by RT-PCR and isolated from China. The product of PCK was cloned into pMD18-T vector, and then transfected Escherichia Coli JMI00. The recombinant plasmids were amplified by PCR and were sequenced. From the nucleotide sequence of the amplified products, phylogenetie analyses were performed and genotypes or subgenotypes were identified. The results indicated that the E2 gene fragment of HB-DCZ strain contained 1277bp nucleotides, and had 89.4%, 70.7%, 97.6%, 68.9%, 67.2% sequence similarity with Osloss, OregonC24V, Changchun184, ZM195, NADL, respectively. In conclusion, HB-DCZ strain is closely related to BVDV Osloss, Changchun184, and belongs to subgenotype lb.