Adaptive genome evolution through fragile sites

2018 Fiscal Year Final Research Report

• Project/Area Number: 15H04403
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Genetics/Chromosome dynamics
• Research Institution: The Graduate University for Advanced Studies
• Principal Investigator: INNAN HIDEKI 総合研究大学院大学, 先導科学研究科, 教授 (90444140)
• Co-Investigator(Kenkyū-buntansha): 八島 亮子 武蔵野大学, 工学部, 助教 (90759573)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 適応進化 / 脆弱部位 / 突然変異ホットスポット

Outline of Final Research Achievements

We aim to demonstrate the evolutionary importance of fragile sites. Fragile sites are hot spots of mutation, which are usually selected against. In this sense, they are evolutionary useless. Here, we hypothesized that a genome has some benefit if it has fragile sites, especially when the host species face environmental changes and has to adapt in a short time. To demonstrate this, we investigated genomes of various species. For example, we found a number of genes have been integrated in the genome of parasite plants, and there seem to be hotspots of integration, where multiple genes are integrated (Kado Inann 2018 Genome Biol. Evol.). We also investigated the genome of domesticated horse, from which we found a number of regions that have changed dramatically in the domestication process.

Free Research Field

ゲノム進化

Academic Significance and Societal Importance of the Research Achievements

脆弱部位は突然変異のホットスポットであるため、基本的には有害な物である。したがって、進化的に一時的に存在するだけで、すぐに淘汰され消滅するものであると考えられている。しかし、この概念は必ずしも正しくない。本研究では、バクテリアから高等生物まで、複数のゲノムを調べることによって、ゲノムの進化速度は一様ではなく、脆弱な速い進化を示す部分と、そうでない部分が存在するこを示した。