P8003 The gene duplication of β-2 microglobulin in Artiodactyla remains intact only in pigs. (1st September 2016)

• Record Type: Journal Article
• Authors: Le, M. T.; Choi, M. K.; Cho, H.; Park, C.
• Is Part Of: Journal of animal science. Volume 94(2016)Supplement 4
• Page Start: 182
• Page End: 182
• Publication Date: 2016-09-01
• Subjects: pig genome -- MHC -- gene duplication -- β-2 microglobulin; Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.2527/jas2016.94supplement4182x
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: From the analysis of the pig genome assembly SSC10.2, we discovered a segmental duplication of ∼48 kb in size containing the entire coding sequence of β-2 microglobulin (B2M) and the protein associated with topoisomerase II homolog 2 (PATL2) genes on pig chromosome 1. Considering B2M as a subunit of the major histocompatibility complex (MHC), based on the finding, we evaluated the functional consequence of B2M duplication in possible strengthening of immune capacity through the increased expression of MHC molecules in pig cells. As a first step, we confirmed the accuracy of the B2M duplication in the pig genome by PCR and direct sequencing of duplication boundaries. Subsequently, we confirmed the copy number of B2M in the pig genome using real-time PCR at the level of mRNA and genomic DNA. We also analyzed and compared the synteny blocks of the corresponding region among pigs and other mammals to check the evolutionary conservation. Our results showed that this duplication has occurred during the speciation of Artiodactyla, but currently remains structurally and functionally intact only in pigs. As a separate experiment, we evaluated changes of protein expression level of MHC on the cell surface after transfecting B2M cDNA to a pig cell line. However, the protein level was similar to that of before transfection in our analysis. Although the functional effect of B2M duplication in pigs is still unclear, this could provide a beneficial effect to immune reaction of pigs. Further analyses are necessary to address this interesting question.