Developmental study of vertebrate jaw evolution by using shark embryos

• Project/Area Number: 24770217
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Developmental biology
• Research Institution: Tokyo Medical and Dental University (2013-2014); Iwate Medical University (2012)
• Principal Investigator: MASAKI Takechi 東京医科歯科大学, 医歯(薬)学総合研究科, テニュアトラック助教 (10455355)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2012: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
• Keywords: 顎 / 形態進化 / トラザメ / 軟骨魚類 / 鰓弓 / 咽頭弓 / 鼓膜 / 中耳 / 咽頭嚢 / 顎口類 / 顎の獲得 / 進化発生学 / Evo-Devo / Dlxコード

Outline of Final Research Achievements

To elucidate the developmental basis of jaw patterning in the vertebrate evolution, I tried to examine jaw development in the shark embryo (Scyliorhinus torazame). I isolated genes that are considered to be involved in jaw patterning in the shark, and examined expression pattern of these genes in shark embryos. Expression pattern of Dlx1-6 genes suggest that jaw patterning along the dorsal-ventral axis in the shark is established by Dlx-code as in the other jawed vertebrates. I also compared expression pattern of Bapx1 gene in the mouse, chick and shark, and found that the position of the expression shifted dorsally in the mammalian lineage. We suggest that this developmental event led to tympanic membrane formation in the lower jaw region in a mammalian ancestor.

Research Products

• [Journal Article] Developmental genetic bases behind the independent origin of the tympanic membrane in mammals and diapsids. (2015)
  • Author(s): Kitazawa T, Takechi M, Hirasawa T, Adachi N, Narboux-Neme N, Kume H, Maeda K, Hirai T, Miyagawa-Tomita S, Kurihara Y, Hitomi J, Levi G, Kuratani S, Kurihara H
  • Journal Title: Nature Communications Volume: 6 Issue: 1 Pages: 6853-6853
  • DOI: 10.1038/ncomms7853
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] The Dlx genes as clues to vertebrate genomics and craniofacial evolution (2013)
  • Author(s): Takechi, M., Adachi N., Hirai, T., Kuratani, S., Kuraku, S.
  • Journal Title: Seminars in Cell and Developmental Biology, 24 (2): 110-118 Volume: 24 Issue: 2 Pages: 110-118
  • DOI: 10.1016/j.semcdb.2012.12.010
  • Peer Reviewed
• [Journal Article] Development of the head and trunk mesoderm in the dogfish Scyliorhinus torazame. II.Comparison of gene expression between the head mesoderm and somites with reference to the origin of the vertebrate head (2012)
  • Author(s): Adachi, N., Takechi M., Hirai T., Kuratani, S.
  • Journal Title: Evolution and Development, 14: 257-276 Volume: 14 Issue: 3 Pages: 257-276
  • DOI: 10.1111/j.1525-142x.2012.00543.x
  • Peer Reviewed
• [Presentation] Comparative developmental analysis of middle ear formation in mouse and chicken embryos (2015)
  • Author(s): Masaki Takechi, Taro Kitazawa, Junko Takei, Yukiko Kurihara, Sachiko Iseki, Hiroki Kurihara, Shigeru Kuratani
  • Organizer: 第120回日本解剖学会総会・全国学術集会
  • Place of Presentation: 神戸国際会議場
  • Year and Date: 2015-03-22
• [Presentation] 顎と中耳の形態形成機構－先天異常から進化まで (2014)
  • Author(s): 武智正樹
  • Organizer: 第3回 硬組織疾患ゲノムセンターセミナー
  • Place of Presentation: 東京医科歯科大学
  • Year and Date: 2014-09-30
  • Invited
• [Presentation] 哺乳類中耳の進化発生学的解析 (2014)
  • Author(s): 武智正樹, 北沢太郎, 栗原由紀子, 井関祥子, 栗原裕基, 倉谷滋
  • Organizer: 日本動物学会第85回仙台大会
  • Place of Presentation: 東北大学
  • Year and Date: 2014-09-13
• [Presentation] 顎・中耳領域の先天異常と形態形成機構について (2014)
  • Author(s): 武智正樹
  • Organizer: 第54回日本先天異常学会学術集会
  • Place of Presentation: 麻布大学
  • Year and Date: 2014-07-26
  • Invited