Evolutionary improvement of mutational robustness at the genomic scale

2018 Fiscal Year Final Research Report

• Project/Area Number: 15KT0078
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Multi-year Fund
• Section: 特設分野
• Research Field: Constructive Systems Biology
• Research Institution: The University of Tokyo (2017-2018); Osaka University (2015-2016)
• Principal Investigator: tsuru saburo 東京大学, 大学院理学系研究科(理学部), 特任助教 (80594506)
• Project Period (FY): 2015-07-10 – 2019-03-31
• Keywords: ゲノム / 変異 / 遺伝子

Outline of Final Research Achievements

Using Escherichia coli, a model bacterium, an evolution experiment was performed under highly mutagenic environment for several years. Analyzing genomic mutations revealed that mutations tends were enriched in genes related to stress response. In addition, growth reduction under highly mutagenic environment was derived not only by deleterious load of the accumulated mutations, but also by another harmful effect associated with mutagenic physiology. Moreover, mutations were likely to be accumulated at a specific sequence motif which consists of few nucleotide at least. These evidence would help us identify specific genes responsible for growth robustness against deleterious mutations at the genomic scale and design mutationally stable genome.

Free Research Field

システムゲノム科学

Academic Significance and Societal Importance of the Research Achievements

変異は、遺伝情報に生じるエラーであり、病気の原因となるだけでなく、有用物質の生産性を低下させる原因になるなど、私たちの日常社会と深い関わりがあります。そのため、変異や変異の影響を抑制する原理の発見や技術開発が多くの学術分野で望まれています。本研究で得られた成果は、変異が細胞の増殖に与える悪影響に注目し、どのような遺伝子群が変異の有害作用の抑制に関わっており、どのような塩基配列であれば変異そのものが生じにくくなるかについて、示唆に富む情報を提供しています。本研究で得られた情報を基礎として発展させれば、変異に頑強でより安定な人工ゲノムを開発するなどの応用が可能になると期待されます。