Research on the genetic networks associated with longevity utilizing the sex determination factors in termites

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K19293
• 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: University of Toyama
• Principal Investigator: Maekawa Kiyoto 富山大学, 学術研究部理学系, 准教授 (20345557)
• Co-Investigator(Kenkyū-buntansha): 宮崎 智史 玉川大学, 農学部, 教授 (20547781)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 社会性昆虫 / シロアリ / 性決定遺伝子 / Doublesex / 生殖カースト / 寿命

Outline of Final Research Achievements

In termites, reproductive individuals are long-lived, especially the kings typically do not get replaced and continue to engage in reproductive activities. Since the sex determination gene Doublesex (Dsx) is expressed only in termite males, it is possible that downstream of Dsx, there is a gene network that supports the high fertility and longevity of kings. The results showed that, in Reticulitermes speratus, multiple genes involved in sperm formation and lifespan were found downstream of Dsx. However, the Dsx targets varied among species, and a common gene network of termites was not identified. Furthermore, there were quite differences in the Dsx gene structure, expression patterns, and genomic positions among species. These diversifications related to Dsx may have greatly contributed to the evolution of termites.

Free Research Field

昆虫生態学，進化発生学

Academic Significance and Societal Importance of the Research Achievements

研究例の多いアリやハチの雄成虫は短命で，シロアリの王の長命性をもたらす分子的な要因が解析された例は殆どない。解析の結果，日本最普通種のヤマトシロアリでは，性的形質の発達を調節する転写因子Doublesex（Dsx）が，精子形成だけでなく，寿命の調節に働く複数の遺伝子の発現に影響することが示唆された。これらは，王の長命性と高い繁殖力をもたらす遺伝子ネットワークの一部を構成する可能性がある。更に，Dsxの構造や発現パターン，標的遺伝子は種間で多様化することも明らかになった。Dsxに関係する変化が，シロアリの生態や形態，発生に大きな影響を与えた可能性を示す重要な成果である。