Characterization and Evolution of MHC Class II B Genes in Ardeid Birds
- 生命科学－已发表论文 
Major histocompatibility complex (MHC) is a multi-gene family that is very suitable to investigate a wide range of open questions in evolutionary ecology. In this study, we characterized two expressed MHC class II B genes (DAB1 and DAB2) in the Grey Heron (Aves: Ardea cinerea). We further developed the primer pairs to amplify and sequence two MHC class II B loci in ten ardeid birds. Phylogenetic analysis revealed that different parts of the genes showed different evolutionary patterns. The exon 2 sequences tended to cluster two gene-specific lineages. In each lineage, exon 2 sequences from several species showed closer relationships than sequences within species, and two shared identical alleles were found between species (Egretta sacra and Nycticorax nycticorax; Egretta garzetta and Bubulcus ibis), supporting the hypothesis of trans-species polymorphism. In contrast, the species-specific intron 2 plus partial exon 3 tree suggested that DAB1 and DAB2 were subject to concerted evolution. GENECONV analyses showed the gene exchange played an important role in the ardeid MHC evolution.
CitationJournal of Molecular Evolution,Volume 72, Numbers 5-6 (2011), 474-483