Expression profile and association analysis of the porcine DQB1 gene with peripheral blood T lymphocyte subsets

Abstract

Major histocompatibility complex (MHC) class II molecules play an important role in immunology by presenting antigens to T lymphocytes. As a key member of the MHC class II gene family, the DQB1 gene is involved in interacting with T cells in immune reactions. This study was designed to screen variations in exon 3 of the DQB1 gene in Large White, Landrace and Songliao Black pigs, and to investigate the association between DQB1 gene polymorphisms and peripheral blood T lymphocyte subsets in Large White samples. In addition, the spatial transcription profile of the DQB1 gene was examined, and the effect of gene polymorphisms on its mRNA level was further analyzed. One missense mutation in exon 3 of the DQB1 gene was first identified by DNA pool sequencing, and samples were genotyped by using the polymerase chain reactionrestriction fragment length polymorphism method. Statistical analysis indicated that the DQB1 genotype was significantly associated with CD4＋CD8－, CD4－CD8＋ and CD4＋/CD8＋ indexes (P<0.05). Analysis of mRNA distribution showed that DQB1 was predominantly expressed in the spleen. However, no significant differences in splenic DQB1 mRNA levels of pigs with different genotypes were observed (P>0.05). These results suggest that the DQB1 gene may be a promising candidate gene for porcine disease resistance.

Keywords

• Pig
• DQB1
• Polymorphism
• T lymphocyte subsets
• Expression