2017 Fiscal Year Final Research Report
Developmental modularities behind evolution of the jaw and middle ear in mammals
Project/Area Number |
26460256
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
General anatomy (including histology/embryology)
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Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
TAKECHI Masaki 東京医科歯科大学, 大学院医歯学総合研究科, テニュアトラック助教 (10455355)
|
Research Collaborator |
FURUTERA Toshiko
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Project Period (FY) |
2014-04-01 – 2018-03-31
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Keywords | 中耳 / 鼓膜 / 外耳道 / 咽頭弓 / 進化発生 / マウス / ニワトリ |
Outline of Final Research Achievements |
We have focused on morphological evolution of the mammalian middle ear and have reported that the tympanic membrane (TM), consisting of the external auditory meatus (EAM) and first pharyngeal pouch, evolved independently in mammalian and diapsid (modern reptiles and birds) lineages. In this study, we compare TM formation along the anterior-posterior axis of pharyngeal arches in mouse and chick embryos. In mouse, TM is formed in the first pharyngeal arch (PA1) and this arch plays a crucial role in TM formation. By contrast, the EAM begins to invaginate at the surface ectoderm of the second pharyngeal arch (PA2) in chick, and the entire TM is formed in PA2. These results indicate that the classical idea of TM formation is not correct in either animal and further strengthen the idea of independent origin of the TM during amniote evolution.
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Free Research Field |
発生生物学
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