インテグリンVLA-4とその対受容体VCAM-1がミオゲネシスにおける役割

G D Rosen¹, J R Sanes, R LaChance

¹Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110.

Cell

|June 26, 1992

まとめ

インテグリンVLA-4とその対受容体VCAM-1は,哺乳類における二次筋形成に不可欠である. これらの分子をブロックすると,新しい筋肉繊維の形成が妨げられ,筋肉の発達におけるその役割が強調されます.

科学分野:

細胞生物学細胞生物学
発達生物学発達生物学について
筋肉生理学筋肉生理学

背景:

哺乳類の筋肉形成の過程であるミオゲネシスは,一次的および二次的ミオゲネシスという2つの異なる段階で行われます.
プライマリミオゲネシスは,ミオブラストの初期融合を伴うもので,プライマリミオチューブを形成する.
次第のミオゲネシスは,追加のミオブラスト (次第ミオブラスト) が既存のプライマリミオチューブに沿って並んで,成人の筋肉繊維の大部分を形成します.

研究の目的:

哺乳類の二次筋形成におけるインテグリンVLA-4とその対受容体VCAM-1の役割を調査する.
筋肉の発達中のVLA-4およびVCAM-1の発現パターンを in vitroおよびin vivoで決定する.
二次性ミオブラストの調整と融合におけるVLA-4-VCAM-1相互作用の機能的重要性を明らかにする.

主な方法:

哺乳類の筋肉細胞を培養して,ミオゲネシスをin vitroで研究する.
筋管形成中のVLA-4とVCAM-1の合成と発現を分析する.
二次筋形成の部位におけるVLA-4およびVCAM-1のインビボ発現パターンを調べる.
VLA-4とVCAM-1に対する抗体を活用して,ミオチューブ形成を阻害し,機能的役割を評価する.

主要な成果:

VLA-4はミオチューブ形成時に誘発され,VCAM-1はミオブラストとミオチューブの両方に存在します.
In vivoでは,VLA-4は一次性および二次性ミオチューブに存在し,VCAM-1は二次性ミオブラストおよびアポスされたミオチューブ領域に発現する.
VLA-4またはVCAM-1を標的とした抗体は,細胞培養実験でミオチューブ形成を著しく抑制しました.

結論:

VLA-4/VCAM-1の相互作用は,哺乳類の二次筋形成において重要な役割を果たしています.
これらの相互作用は,おそらく,第2次ミオブラストが,第1次ミオチューブに沿って並ぶこと,および/またはその後の融合に影響する.
VLA-4とVCAM-1をターゲットにすることは,筋肉の発達と再生を調節するための潜在的な道を示しています.

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