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Organotypic Collagen I Assay: A Malleable Platform to Assess Cell Behaviour in a 3-Dimensional Context
Published on: October 13, 2011
Integrin alpha1beta1 mediates a unique collagen-dependent proliferation pathway in vivo
A Pozzi1, K K Wary, F G Giancotti
1Department of Cell Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.
The Journal of Cell Biology
|July 29, 1998
Summary
Integrin alpha1 plays a unique role in cell proliferation. Alpha1-deficient mice show reduced dermal fibroblast growth, indicating integrin alpha1
Area of Science:
- Cell Biology
- Biochemistry
- Dermatology
Background:
- Integrin activation by extracellular matrix proteins regulates cell survival and proliferation.
- Integrin alpha1 (ITGA1) is a collagen receptor implicated in cell growth.
- The specific role of integrin alpha1 in collagen-mediated signaling remains unclear.
Purpose of the Study:
- To investigate the in vivo and in vitro role of integrin alpha1 in regulating cell growth and survival.
- To determine if integrin alpha1 is essential for collagen-induced cell proliferation.
- To elucidate the downstream signaling pathways regulated by integrin alpha1.
Main Methods:
- Utilized integrin alpha1-null mice and their embryonic fibroblasts.
- Assessed dermal fibroblast proliferation in vivo and in vitro.
- Analyzed cell attachment, spreading, and activation of signaling proteins (Shc, Grb2, MAPK) on collagenous substrata.
Main Results:
- Alpha1-deficient mice exhibit a hypocellular dermis and reduced embryonic dermal fibroblast proliferation.
- In vitro, alpha1-null fibroblasts show reduced proliferation on collagen, despite normal attachment and spreading.
- Deficiency in alpha1 leads to impaired Shc and Grb2 recruitment, and subsequent mitogen-activated protein kinase activation on collagen.
Conclusions:
- Integrin alpha1 is the sole collagen receptor capable of activating the Shc-mediated growth pathway.
- Integrin alpha1 plays a unique and critical role in regulating cell proliferation on collagenous matrices, both in vivo and in vitro.
- This highlights a specific mechanism by which collagen receptors influence cell growth and survival.
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