Coevolution between HLA and bacteria or viruses

2014 Fiscal Year Final Research Report

• Project Area: HLA polymorphism, disease and evolution
• Project/Area Number: 22133007
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: The Graduate University for Advanced Studies
• Principal Investigator: SATTA Yoko 総合研究大学院大学, 先導科学研究科, 教授 (20222010)
• Research Collaborator: YASUKOCHI Yoshiki ; LAU Quintin ; FUJITO Naoko
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 自然選択 / 免疫機構 / 進化速度 / ペプチド / 病原菌 / ペプチド結合領域

Outline of Final Research Achievements

Human major histocompatibility complex (human MHC, HLA) genes play an important role in the acquired immune system so as to recognize infection by bacteria and viruses and to activate the immune system in order to protect a body against the infection. Because HLA needs to recognize unpredictable pathogens, HLA genes are the most polymorphic loci among the human genome. We have examined mechanisms for the generation and the maintenance of HLA polymorphisms, and results were as follows: 1) Estimates of the strength of natural selection operating on the six HLA loci is at the most 3% 2) Amino acid substitution rate at the peptide binding region (PBR) among HLA-DRB1 allelic lineages is not uniform, 3) Human-specific DRB1 allelic lineages, which diverged 28 myr ago, resulted from the loss of the allelic lineages in other primates. Furthermore, the relationship between genetic distances between HLA-DRB1 alleles and the extent of repertories of its binding peptides were elucidated .

Free Research Field

分子進化学、集団遺伝学、進化生理学