Abstract：Sheep mannose-binding lectin(MBL) is an important part of the body's natural immune system. Nine pairs of primers were designed according to human(Homo spiens) and bovine(Bos taurus) MBL gene sequence, combined with PCR technique to amplify the MBL gene of sheep(Ovis aries). Cloning, sequencing and splicing to analyze bioinformations with the DNAMAN software and online tools. The results showed that sequence of DNA of the sheep MBL gene was 4 462 bp containing promoter, four exons, three introns, which encoded 249 animo acids, submitted it to GenBank (Accession No. FJ977629). Its amino acid sequence had an overall similarity with a comparable region of bovine MBL-C gene(96.39%), phylogenetic tree of amino acid analysis indicated that the sheep MBL gene was MBL-C. Expasy were employed to predict specific structure and function of sheep MBL gene, 1~19 amino acids were signal peptide region, exon 1 encoded N-terminus cysteine-rich domain and 8 Gly-X-Y repetitive sequences of collagen-like domain, and exon 4 encoded carbohydrate recognition domain(CRD) which had common features of C-type lectin. This study is the first report about complete genomic DNA sequence data of sheep MBL gene, and it provides basal data for further study on the structure, function and defects in the molecular mechanism of MBL.
