title: Evolution of MHC class I genes in two ancient fish, paddlefish (Polyodon spathula) and Chinese sturgeon (Acipenser sinensis).
abstract: Here we present the first isolation of major histocompatibility complex (MHC) class I genes from two ancient fish, paddlefish (Polyodon spathula) and Chinese sturgeon (Acipenser sinensis). Seventeen sequences obtained showed high polymorphism and positive natural selection with dN/dS>1. Evolutionary relationships revealed that sequences from paddlefish and Chinese sturgeon distinguished from other vertebrate class I and had an intermingling of alleles, which indicates that Acipenseriformes have a common ancestral gene of class I and a trans-species polymorphism across Acipenseriformes. We also found clear evidence of recombination among class I genes of paddlefish and Chinese sturgeon.
authors.affiliation: Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Dengqiang
authors.initials: D
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Zhong
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Wei
authors.forename: Xiaoni
authors.initials: X
authors.lastname: Gan
authors.forename: Shunping
authors.initials: S
authors.lastname: He
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002681:China; D019143:Evolution, Molecular; D005399:Fishes / Q000235:genetics*; D005805:Genes, MHC Class I / Q000235:genetics*; D015789:HLA-A2 Antigen / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D011995:Recombination, Genetic / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D015789:HLA-A2 Antigen