title: Molecular characteristics of the SLA-2 gene from Chinese Hebao pigs.
abstract: To study the molecular characteristics of swine leukocyte antigen (SLA) class I from the Hebao pig, a rare inbreed in China, a pair of primers was designed to amplify the SLA-2 gene (SLA-2-HB) and then the molecular characteristics of the gene were analyzed by computer. After cloning, sequencing and computer analysis, four SLA-2-HB alleles were found, all of 1119 bp. Sites 3-1097 were an open reading frame encoding 364 amino acids with two sets of intra-chain disulfide bonds comprising four cysteines situated in sites 125, 188, 227 and 283. By alignment of SLA-2-HB sequences with other SLA-2 alleles in the DNA Data Bank of Japan/European Molecular Biology Laboratory/GenBank database, nine key variable amino acid sites were found in the extracellular domain of the SLA-2-HB alleles at sites 23(F), 24(I), 43(A), 44(K), 50(Q), 73(N), 95(I), 114(R) and 216(S), which could be used to differentiate other SLA-2 alleles. The amino acid identities between SLA-2-HB and other SLA-2, SLA-3 and SLA-1 alleles were 87.1-97.0%, 85.0-93.9% and 83.3- 88.6%, respectively. The phylogenetic tree of SLA-2-HB showed that it was relatively independent of the other SLA-2 genes. Furthermore, the SLA-2-HB alleles were similar to HLA-B15 and HLA-A2 functional do- mains and preserved some functional sites of HLA-A2. It was concluded that SLA-2-HB is an allele of SLA-2 and that the Hebao pig might have evolved independently in China.
authors.affiliation: Department of Biochemistry and Molecular Biology, College of Bioengineering, Dalian University, Dalian, Liaoning 116622, China. gfsh0626@126.com
authors.forename: F-S
authors.initials: FS
authors.lastname: Gao
authors.forename: J
authors.initials: J
authors.lastname: Bai
authors.forename: X-H
authors.initials: XH
authors.lastname: Zhang
authors.forename: W-J
authors.initials: WJ
authors.lastname: Zhang
authors.forename: D
authors.initials: D
authors.lastname: Guo
authors.forename: S
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000483:Alleles; D000818:Animals; D030541:Databases, Genetic; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics*; D010802:Phylogeny; D013552:Swine / Q000235:genetics*
chemical_list: D015395:Histocompatibility Antigens Class I