| Interferon exert the biological activities such as antivirus activity, antiproliferative actions and immune response through binding to their receptors. Interferon receptor play a critical role in the signal transmission and activation of transcription of interferon genes. This paper cloned,expressed IFN-α , IFN- β ,IFNAR1,IFNAR2 genes, firstly cloned IFNGR2 gene of HuiYang chicken and detected their transcript levels in peripheral blood leukocyte and tissues; secondary structures and interactions of IFN- α / β and their receptors were analysed.IFN- α gene was cloned from liver genomic DNA of HuiYang chicken.The homologies were from 96.9% to 97.9% between HuiYang IFN- α and IFN- α s on Genbank, indicating this IFN- α gene was a new subtype.The genes of IFN- β were cloned from liver genomic DNA of HuiYang chicken and Arbor Acres respectively,exhibiting 99.84% and 100% identity to gene of IFN- P of white leghorn.IFN- β was a single copy gene without subtype until now. IFN- α ,IFN- β genes were subcloned into pGEX-6P-1, the recombinant plasmids were transformed into BL21 and expressed.The GST fusion proteins in the supernatant were purified using Glutathione Separose 4B column and examined using western-blot.Recombinant IFN- α ,IFN- β expressed in E.coli exert high antiviral activities as 7.9 × 10~5U/mg and 6.4 × 10~4 U/mg respectively.IFNARl and IFNAR2 genes of HuiYang chicken were cloned from liver total RNA.Comparison of HuiYang IFNARl with gallus gallus IFNAR1,the homology of amino acids sequences was 99.47%; there was 99.35% homology between amino acid sequence of Huiyang IFNAR2 and that of gallus.gallus. HuiYang IFNARl, IFNAR2 were new subtypes.The extracellular part of HuiYang IFNAR1 was composed of four tipical conserved motif of interferon receptor family(Fibronectin Ⅲ molecule ) on 35-133, 134-237, 240-319 and 341-447 of amino acid sequence,which connected by two linkers on 123-129 and 302-321.There were two Fibronectin Ⅲ molecules on 37-93 and 129-240 of IFNAR2 amino acid sequences,which connected by two linkers on 94-105 and 157-166. IFNAR1EC and IFNAR2EC genes were subcloned into pGEX-6P-l, the recombinant plasmids were transformed into BL21 and expressed.The soluble proteins were purified using Glutathione Separose 4B column and examined using western-blot.The full length cDNA of IFNGR2 was firstly cloned from HuiYang chicken spleen total RNA using 5' RACE and 3' RACE. This 2221bp gene encoded 334 aminoacids ,with 28, 29%, 30% identity with amino acids of rat, mouse, human IFNGR2 respectively and given name as HuiYang IFNGR2. Extracellular part of HuiYang IFNGR2 contained two FNⅢ domains on 31-119 ,126-21 of amino acid sequences and two linkers on 96-115,115-131. HuiYang IFNGR2 gene was localized on the chromosome1q26 of chicken in tandem with IFNARl, IL-10R2 and IFNAR2 through Genome BLAST.To analyse the expression of IFN- α , IFN- β ,IFNAR1,IFNAR2 and IFNGR2 in different organs and peripheral blood leukocyte (PBL) using Northern blot and RT-PCR, the total RNAs were extracted from spleen,thymus, muscle ,caecum tonsil,cardiac muscle,cloacal bursa,liver,kidney ,unstimulated PBL and stimulated PBL with ConA .IFN- α and IFN- β were detectable when PBL stimulated with ConA,but not detectable in the organs and unstimuted PBL IFNAR1 and IFNGR2 was highly expressed in unstimulated PBL,but IFNAR2 was lowly expressed.Expression of of IFNAR1,IFNAR2 and IFNGR2 did not increased after ConA activation.IFNARl,IFNAR2 and IFNGR2 transcripts were detectable in spleen, thymus, cloacal bursa and caecum tonsil and IFNGR2 was also also detected in muscle,cardiac muscle,cloacal bursa,liver,kidney.RT-PCR results consisted with the results of Nothern blot.The high expression of interferon receptor in immune organs indicated interferon receptor may play important role in antivirus and immue response.The Gel-filtration and GST interacting trials confirmed stalbe formation of binary complex of IFN- α -IFNAR2EC and IFN- β -IFNAR2EC in vitro;IFNARlEC did not bind to IFN- β , IFN- β or IFNAR2EC. IFN-α...
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