Resistance of plant genomes to gene copy number reduction

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K21449
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 45:Biology at organismal to population levels and anthropology, and related fields
• Research Institution: Fukui Prefectural University
• Principal Investigator: Kazama Yusuke 福井県立大学, 生物資源学部, 教授 (80442945)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: 遺伝子量補正 / シロイヌナズナ / RNAseq / ゲノム / 重イオンビーム

Outline of Final Research Achievements

Gene dosage compensation is a phenomenon known mainly in animal sex chromosomes and is a mechanism by which gene expression is regulated at the same level between male (♂) and female (♀) chromosomes. We discovered that the X chromosome of the higher plant, Silene latifolia, undergoes gene dosage compensation in response to a sudden Y chromosome deletion. To examine whether this might be a general phenomenon in plants, rather than a phenomenon limited to sex chromosomes. Therefore, we investigated whether gene dosage correction also occurs in Arabidopsis autosomes when the number of copies of gene is reduced to half. The results showed that the expression levels of the majority of genes were reduced by half compared to the wild type, indicating that immediate gene dosage compensation does not occur in Arabidopsis autosomes.

Free Research Field

植物遺伝学

Academic Significance and Societal Importance of the Research Achievements

シロイヌナズナの染色体を倍数化したり異数化させた場合には、遺伝子の発現量が異なる例が報告されており、倍数化した個体は表現型も大きく異なる。これに対し、ヘテロの欠失についての知見はなかった。本研究では、ヘテロの欠失が起きた場合にそこに存在する遺伝子の発現量がおおよそ半減し、表現型にも影響が現れることを明確に示した。中には、ヘテロ欠失をもつと野生型よりも生重量が多くなる個体も見られた。これらの結果は、ヘテロの欠失も育種上有用であることを示す。ヘテロの欠失は重イオンビーム照射において頻繁に誘発されるため、今後の有効利用が期待される。