Elucidation of the process of duplicated gene independence using FSH and LH as a model

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K16176
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 44040:Morphology and anatomical structure-related
• Research Institution: The University of Tokyo
• Principal Investigator: Fujimori Chika 東京大学, 大気海洋研究所, 特任研究員 (50750775)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: メダカ / FSH / LH / ゲノム進化 / エンハンサー

Outline of Final Research Achievements

The genes fshb and lhb, which produce follicle-stimulating hormone (FSH) and luteinizing hormone (LH), are paralogous genes derived from the duplication of identical genes. They are co-expressed in the same pituitary cells in mammals, whereas they are expressed in separate cells in teleost fish. In this study, we investigated how the expression patterns of fshb and lhb changed during evolution by introducing the enhancer sequences of fshb and lhb from co-expressing and differentially expressing species into medaka and checking the reporter activity in the pituitary cells of medaka. Immunohistochemistry and in situ hybridization on the same sections revealed the correspondence between fshb/lhb co-expressing cells of co-expressing species and fshb- and lhb-expressing cells of differentially expressing species.

Free Research Field

生殖生物学

Academic Significance and Societal Importance of the Research Achievements

本研究では、パラログ遺伝子であるfshb, lhb進化上での発現パターンの変化について、種間での各発現細胞の対応関係を実験的に示すことができた。このことは、パラログ遺伝子が発現分化するプロセスを明らかにできた初めての例となるだけではなく、異種のエンハンサー活性をモデル動物内で再現、細胞レベルで解析することによって、進化の過程で起こった発現制御配列の進化をモデル動物上でレポーター発現として可視化する方法が有効であることを示した。