Inositol 1,4,5-trisphosphate receptor 1 (ITPR1) is an important intracellular channel for releasing Ca²⁺. In order to investigate the effects of the ITPR1 overexpression on Ca²⁺ concentration and lipid content in duck uterine epithelial cells and its effects on calcium transport-related genes, the structural domain of ITPR1 gene of duck was cloned into an eukaryotic expression vector and transfected into duck uterine epithelial cells. The overexpression of the ITPR1 gene, the concentration of Ca²⁺, the lipid content, and the expression of other 6 calcium transport-related genes was determined. The results showed that the concentration of Ca²⁺ in uterine epithelial cells was significantly reduced after transfection (P<0.05), the triglyceride content was significantly increased (P<0.01), and the high-density lipoprotein content was significantly decreased (P<0.01). The correlation analysis results showed that the overexpression of the C-terminal half of the ITPR1 gene was significantly positively correlated with the total cholesterol content (P<0.01), which was significantly positively correlated with the low-density lipoprotein content (P<0.05). The overexpression of the N-terminal half of the ITPR1 gene was significantly positively correlated with the triglyceride content (P<0.01), which was significantly negatively correlated with the concentration of Ca²⁺ (P<0.05). RT-qPCR results of 6 calcium transport-related genes showed that the overexpression of the C-terminal half of the ITPR1 gene significantly inhibited the expression of the IP3R2, VDAC2 and CAV1 genes, and the overexpression of the N-terminal half of the ITPR1 gene significantly promoted the expression of the IP3R3 and CACNA2D1 genes. In conclusion, the ITPR1 gene overexpression can promote Ca²⁺ release in duck uterus epithelial cells, promote the synthesis of triglyceride, low-density lipoprotein and cholesterol, and inhibit the production of high-density lipoprotein, and the ITPR1 gene overexpression affected the expression of all 6 calcium transport-related genes.
Animals ; Calcium/metabolism* ; Ducks/genetics* ; Epithelial Cells ; Female ; Inositol ; Inositol 1,4,5-Trisphosphate Receptors ; Lipids ; Uterus

Stearoyl-CoAdesaturase-1 (SCD-1) is a key regulator of monounsaturated fatty acid synthesis. It plays a vital role in lipid synthesis and metabolism. Ca²⁺ is an important cation in the body and plays an important role in the organism. The aims of this study were to investigate the correlation of SCD-1 gene overexpression with lipid indexes and calcium ion level. The pcDNA3.1 (+) + SCD-1 +Flag eukaryotic expression vector and cultured duck uterine epithelial cells were co-transfected. The overexpression of SCD-1 gene was measured using the Flag Label Detection Kit. Ca ions and lipid contents were detected through Fluo-3/AM Calcium Ion Fluorescence Labeling method and Lipid Measuring Kit, respectively. SCD-1 gene overexpression was negatively correlated with triglyceride (TG) and high-density lipoprotein cholesterol (HDL-C), and positively correlated with Ca ion, total cholesterol (TC), very low-density lipoprotein cholesterol (VLDL-C) and low density lipoprotein cholesterol (LDL-C) levels. Meanwhile, Ca ion was positively correlated with TG, LDL-C and HDL-C contents, and negatively correlated with TC and VLDL-C levels. Overexpression of SCD-1 gene could regulate Ca ion secretion, as well as lipid synthesis and transport in duck uterine epithelial cells.
Animals ; Calcium ; metabolism ; Coenzyme A Ligases ; genetics ; Ducks ; Epithelial Cells ; chemistry ; enzymology ; Gene Expression ; Ions ; Lipids ; genetics ; Triglycerides ; metabolism

To study the interaction between C4b-binding protein (C4BP) and Riemerella anatipestifer (RA), we cloned duck C4BPα, conducted prokaryotic expression and prepared the polyclonal antibody by immunizing mice. Then indirect immunofluorescence assay and dot blotting hybridization assay were used to verify the interaction between C4BP and RA. The full length of duck C4BPα nucleotide sequence was 1 230 bp, with the highest similarity to chicken C4BPα (82.1%). Phylogenetic tree analysis showed that duck C4BPα and chicken C4BPα were on the same phylogenetic tree branch and the genetic evolution relationship between them was the closest. C4BPα was efficiently expressed in Escherichia coli BL21 (DE3). The recombinant proteins existed in intracellular soluble form. The titer of polyclonal antibody was more than 1:10 000 and polyclonal antibodies could specifically recognize the recombinant proteins. The results of indirect immunofluorescence assay and dot blot hybridization assay showed that RA could interact with duck C4BP. The results provide a basis to further reveal the pathogenesis of RA.
Animals ; Cloning, Molecular ; Complement C4b-Binding Protein ; chemistry ; genetics ; metabolism ; Ducks ; classification ; genetics ; microbiology ; Gene Expression Regulation ; Mice ; Phylogeny ; Riemerella ; metabolism

In July 2009, some farms of breeding Muscovy ducks on the peak of egg laying suffered the decrease of hatching rate and the quality of the eggs showing low mortality and no evident respiratory symptoms. The swelling and congestive ovary was visible after autopsy. This study was brought out for the diagnosis of these cases. The virus was isolated and identified by the methods of virus culture in chicken embryo, physical and chemical properties test, hemagglutinin test, NDV (Newcastle diseases Virus) interference test, electron microscope observation, pathogenicity test and the gene sequence analysis. The results indicated the virus showed the characters of inducing dwarf embryo after inocubation, the sensibility to lipid solvent and the hemagglutination capacity after pancreatic enzyme treatment, the typical morphology of coronavirus, the interference to NDV replication and the homology among 84.7% - 99% of the particial N gene sequences to the reference IBV (Avian infectious bronchitis virus) strains. The strain was identified as IBV isolate and this study confirmed the pathogenicity of IBV to Muscovy ducks.
Amino Acid Sequence ; Animals ; Chick Embryo ; Coronavirus Infections ; veterinary ; virology ; Ducks ; virology ; Female ; Infectious bronchitis virus ; classification ; genetics ; isolation & purification ; Molecular Sequence Data ; Phylogeny ; Poultry Diseases ; virology ; Sequence Alignment

Avian leukosis virus subgroup J (ALV-J) is an avian retrovirus that can induce myelocytomas. A high-frequency mutation in gene envelope endows ALV-J with the potential for cross-species transmission. We wished to ascertain if the ALV-J can spread across species under selection pressure in susceptible and resistant hosts. First, we inoculated (in turn) two susceptible host birds (specific pathogen-free (SPF) chickens and turkeys). Then, we inoculated three resistant hosts (pheasants, quails and ducks) to detect the viral shedding, pathologic changes, and genetic evolution of different isolates. We found that pheasants and quails were infected under the selective pressure that accumulates stepwise in different hosts, and that ducks were not infected. Infection rates for SPF chickens and turkeys were 100% (16/16), whereas those for pheasants and quails were 37.5% (6/16) and 11.1% (3/27). Infected hosts showed immune tolerance, and inflammation and tissue damage could be seen in the liver, spleen, kidneys and cardiovascular system. Non-synonymous mutation and synonymous ratio (NS/S) analyses revealed the NS/S in hypervariable region (hr) 2 of pheasants and quails was 2.5. That finding suggested that mutation of isolates in pheasants and quails was induced by selective pressure from the resistant host, and that the hr2 region is a critical domain in cross-species transmission of ALV-J. Sequencing showed that ALV-J isolates from turkeys, pheasants and quails had moved away from the original virus, and were closer to the ALV-J prototype strain HPRS-103. However, the HPRS-103 strain cannot infect pheasants and quails, so further studies are needed.
Amino Acid Sequence ; Animals ; Avian Leukosis ; transmission ; virology ; Avian Leukosis Virus ; classification ; genetics ; physiology ; Chickens ; Ducks ; virology ; Galliformes ; virology ; Host Specificity ; Molecular Sequence Data ; Poultry Diseases ; transmission ; virology ; Quail ; virology ; Sequence Alignment ; Turkeys ; virology ; Viral Envelope Proteins ; chemistry ; genetics ; metabolism

To construct a bait expression vector containing the duck circovirus Cap gene for use in the yeast two-hybrid system, the whole cap codon-optimized gene was inserted into pGBKT7 vector and confirmed by PCR, restriction enzyme digestion, and sequence analysis. After transformation into a Y2HGold yeast strain, the expression of Cap protein was analyzed by Western blotting. Toxicity and self-activation of the bait protein were detected using different dropout minimal base. PCR reaction, restriction enzyme digestion, and sequencing analyses indicated that the duck circovirus Cap gene was correctly inserted into pG- BKT7. Western blotting showed that the whole Cap protein was expressed. The recombinant bait protein had no toxicity and self-activation. Therefore, the bait vector with the Cap gene was constructed successfully, providing a foundation for future screening for interacting proteins in the yeast two-hybrid system.
Animals ; Capsid Proteins ; genetics ; metabolism ; Circovirus ; classification ; genetics ; isolation & purification ; Cloning, Molecular ; Ducks ; Genetic Vectors ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; Saccharomyces cerevisiae ; genetics ; metabolism ; Two-Hybrid System Techniques

Toll-like receptor 5 (TLR5) is responsible for the recognition of bacterial flagellin in vertebrates. In the present study, the first TLR5 gene in duck was cloned. The open reading frame (ORF) of duck TLR5 (dTLR5) cDNA is 2580 bp and encodes a polypeptide of 859 amino acids. We also cloned partial sequences of myeloid differentiation factor 88, 2'-5'-oligoadenylate synthetase (OAS), and myxovirus resistance (Mx) genes from duck. dTLR5 mRNA was highly expressed in the bursa of Fabricius, spleen, trachea, lung, jejunum, rectum, and skin; moderately expressed in the muscular and glandular tissues, duodenum, ileum, caecum, and pancreas; and minimally expressed in the heart, liver, kidney, and muscle. DF-1 or HeLa cells transfected with DNA constructs encoding dTLR5 can activate NF-kappaB leading to the activation of interleukin-6 (IL-6) promoter. When we challenged ducks with a Herts33 Newcastle disease virus (NDV), mRNA transcription of the antiviral molecules Mx, Double stranded RNA activated protein kinase (PKR), and OAS was up-regulated in the liver, lung, and spleen 1 and 2 days post-inoculation.
2',5'-Oligoadenylate Synthetase/genetics/metabolism ; Animals ; Cell Line ; *Cloning, Molecular ; Ducks ; Gene Expression Regulation/*physiology ; Humans ; Immunity, Innate ; Myeloid Differentiation Factor 88/genetics/metabolism ; Myxovirus Resistance Proteins/genetics/metabolism ; Newcastle Disease/metabolism ; Newcastle disease virus/classification ; RNA, Messenger/genetics/metabolism ; Species Specificity ; Toll-Like Receptor 5/genetics/*metabolism

New epidemic broke out in recent year which was suspected to be caused by variant Muscovy duck parvovirus (MDPV). For this reason, new MDPV detection methods are needed for the new virus strains. In this study, a pair of primers were designed according to the full-length genome of MDPV strain SAAS-SHNH, which were identified in 2012, and were used to amplify the vp3 gene of MDPV by polymerase chain reaction. After being sequenced, the vp3 gene was subcloned into the prokaryotic expression vector PET28a. The recombinant plasmid was transformed into E. coli BL21 and induced with IPTG. SDS-PAGE and Western blotting analysis showed the MDPV vp3 gene was successfully expressed. After being purified by Ni2+ affinity chromatography system, the recombinant protein was used as antigen to immunize rabbits to obtain antiserum. Western blotting analysis showed that the acquired antiserum could react specifically with VP3 protein of J3D6 strain and MDPV vaccine strain. The antiserum could also be used for detection of cultured MDPV from primary duck embryo fibroblasts by immune fluorescence assay (IFA). It could be concluded that the VP3 protein and its antibody prepared in the research could be used for detection of VP3 antiserum and antigen respectively.
Animals ; Blotting, Western ; DNA Primers ; Ducks ; virology ; Electrophoresis, Polyacrylamide Gel ; Immune Sera ; biosynthesis ; Parvovirus ; Polymerase Chain Reaction ; Rabbits ; Recombinant Proteins ; genetics ; Viral Proteins ; genetics

Rolling circle amplification (RCA) is a newly developed experimental technique that can specific ally amplify circular DNA. Since 2008, RCA has been extensively used in hepatitis B virus (HBV) research, such as the amplification of the full-length sequence of the HBV genome, and the analysis of the drug-resistant mutations of HBV covalently closed circular DNA (cccDNA), amongst others. To create an easy assay for the analysis of duck hepatitis B virus (DHBV) cccDNA, this study established an RCA-based method. DHBV cccDNA was amplified from the DHBV DNA samples of duck liver with four pairs of sulfur-modified primers, which were designed according to the highly conserved sequence of DHBV using sera DHBV DNA as the negative control. DHBV cccDNA was detected in the obtained RCA products by the sequencing of RCA amplicons that were amplified with primer pairs on both sides of the gap of DH BV relaxed circular DNA, rather than by digesting RCA products with a restriction enzyme. The liver and sera DHBV DNA samples of 39 ducks infected with DHBV were examined with the RCA-based DHBV cccDNA detection method, and the results showed that while DHBV cccDNA was detected from all 39 liver DHBV DNA samples, no DHBV cccDNA was found in any of the sera DHBV DNA samples. These results suggest that the method established in the study is highly specific and sensitive for the detection of DHBV cccDNA. The establishment of this RCA-based DHBV method for cccDNA detection lays the groundwork for using a DHBV model to study the role of cccDNA in the pathogenesis of hepatitis B and to evaluate the effect of anti-virus therapies.
Animals ; DNA Primers ; genetics ; DNA, Circular ; genetics ; DNA, Viral ; genetics ; Ducks ; Hepadnaviridae Infections ; veterinary ; virology ; Hepatitis B Virus, Duck ; genetics ; isolation & purification ; Liver ; virology ; Polymerase Chain Reaction ; methods ; Poultry Diseases ; virology

OBJECTIVETo analyze the genetic composition of a novel H2N3 virus isolate identified from a duck cage swab in a live poultry market (LPM) in 2009 in Guangdong province of China.

METHODSPCR-positive specimens were inoculated into embryonated chicken eggs and subtyped by conventional RT-PCR. All segments of the virus A/environment/Guangdong/2/2009 were sequenced, and phylogenetic trees were constructed and analyzed.

RESULTSThe genes of this virus belong to Eurasian-lineage avian viruses. The virus is a reassortant with the HA gene from an H2N2 virus and the NA gene from an H5N3 virus. The PB1, PB2, and NP genes were from an H4N6 virus, the PA was from an H3N8 virus, the M gene was from an H1N3 virus, and the NS gene was from an H10N6 virus.

CONCLUSIONA novel avian-origin reassortant H2N3 influenza virus was detected in a live poultry market. Its potential impacts and evolution should be closely monitored.

Animals ; China ; Ducks ; virology ; Genome, Viral ; Influenza A virus ; genetics ; isolation & purification ; Influenza in Birds ; virology ; Phylogeny