Cross talk among sex determination cascade, gene dosage compensation, and recombination supression in the silkworms

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H02482
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Insect science
• Research Institution: The University of Tokyo
• Principal Investigator: Shimada Toru 東京大学, 大学院農学生命科学研究科(農学部), 教授 (20202111)
• Co-Investigator(Kenkyū-buntansha): 勝間 進 東京大学, 大学院農学生命科学研究科(農学部), 准教授 (20378863) ; 木内 隆史 東京大学, 大学院農学生命科学研究科(農学部), 助教 (60622892)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 性決定 / 遺伝子量補正 / カイコ / チョウ目 / 性染色体 / 遺伝子ノックアウト / ゲノム編集

Outline of Final Research Achievements

We have revealed that the femaleness of the silkworm, Bombyx mori, is determined by a female-specific small RNA (Fem piRNA) derived from W chromosome, which suppresses expression of the male determining gene, Masc located on the Z chromosome. In this project, in order to clarify the molecular function of Masc, we performed experiments using genetically modified Masc proteins. As a result, we revealed that the zinc finger domain is not necessary, and the cysteine residue near the center is essential for sex determination. In addition, we found that the Masc ortholog in a bombycid, Trilocha varians, also determines the maleness. Furthermore, we clarified that the Masc knockout silkworms cause male-specific lethality at the embryonic stage.

Free Research Field

昆虫遺伝学