Cloning And Sequence Analysis Of β-defensins Gene And A Preliminary Study On Protein Function From The Capital Immune Organ Of Ostrich

Antibacterial peptide are widely exist in a variety of organisms,which have broad-spectrum antibiosis, the regulation of the immune and inhibit tumor and other biological functions. antibacterial peptide expressed in poultry are mainlyβ-defensin. The main tests for the African ostrich are major immune organsβ-defensin gene cloning, sequence analysis and antibacterial activity,Also compared with Gushi Chicken major immune organsβ-defensin gene.The research refer to GenBank already deliver NM20440992 sequences, according to the design principle of PCR primers and with the software of molecular biology designed primers.Extracted RNA From African ostrich and Gushi chicken major immune organs - thymus, spleen and Bursa, RT-PCR amplication about 195bp gene fragments, and clone PMD19-T Vector, establish PMD19-Gal-2 of recombinant plasmid, PCR, the enzyme cut identification and DNA gene sequence identification, the gene was amplified are the purpose ofβ-defensins gene. Comparative indicate: African ostrich major immune organsβ-defensin gene sequences are 195 bp, code 64 amino acid sequences, compared with AF033338(435bp)(THP2),DQ858339(195bp),DQ858312(195bp),DQ858299(195bp), homology are more than 90 percent. The Gushi chickenβ-defensin genes are closest with Gal-2, and also closer With Meleagris gallopavo heterophilic leukocytes defensins gene.African ostrich defense gene and Gal-2, THP2 genetic differentiation comes from the same branch, that their relationship is relatively closer.This can be yield African ostrich, Gushi chicken and turkeyβ-defensin gene may be at the origin of a common ancestor.Study on extraction and antibacterial activity of African ostrich thymus, spleen and bursal organizations defensins. Extracted protein from the African ostrich thymus, spleen and bursal by acid extraction, agarose diffusion method determined it's antibacterial activity, then determined MIC. Use the relationship between chicken and African ostrich, according to already deliverde sequences of Gal-2 to design primers, and faninaly cloning theβ-defensins successfully.This mathod surmounted the disadvantage of multiplicity and time-consuming by RACE. At the same time, antibacterial activity and the determination about its minimum inhibitory concentration provid a good theory for future study .