Tbx2は,内側と外側の毛細胞の分化の主なレギュラーです

Jaime García-Añoveros^1,2,3,4, John C Clancy⁵, Chuan Zhi Foo^5,6

¹Department of Anesthesiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA. anoveros@northwestern.edu.

Nature

|May 4, 2022

まとめ

転写因子Tbx2は,内毛細胞 (IHC) の分化と,小の内毛細胞と外毛細胞 (OHC) の明確な同一性を維持するために不可欠です.

科学分野:

発達生物学
聴覚神経科学
遺伝学

背景:

コクリアには,感覚伝達のための内毛細胞 (IHC) と,増幅のための外毛細胞 (OHC) がある.
OHCの差異化にはINSM1のような転写因子が含まれているが,IHCの差異化を調節する因子は知られていなかった.
INSM1は通常,OHCがIHCになるのを防ぎ,その欠如はIHC遺伝子を発現させるOHCにつながります.

研究の目的:

内毛細胞 (IHC) と外毛細胞 (OHC) の分化に関与する主要な調節体を特定する.
コクレアの毛細胞のアイデンティティの確立と維持におけるTbx2の役割を調査する.
Tbx2 と INSM1 の間の関係を毛細胞運命を決定する.

主な方法:

ネズミの胚性および産後毛細胞におけるTbx2の遺伝的除去
OHCとIHCマーカーを含む遺伝子発現パターンの分析
OHCにおけるTbx2の子宮外発現は,その機能的役割を評価する.

主要な成果:

胚性IHCにおけるTbx2の除去により,OHCマーカーを発現するOHCに変異した.
Tbx2はINSM1にエピスタティックに作用し,正常なIHCの分化とOHCからIHCへの変異を防ぐことが重要です.
産後IHCにおけるTbx2の除去により,IHCが成熟したOHCに直接変換され,OHCにおける子宮外Tbx2により,IHCになった.

結論:

Tbx2は,IHCを指定し,OHCから区別するために必要な,そして十分なマスターレギュラーです.
Tbx2は,毛細胞のアイデンティティを維持する上で,発達過程で重要な役割を果たします.
Tbx2の機能を理解することで聴覚感覚細胞の分化に関する分子機構の洞察が得られます

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