Physiological type I collagen organization induces the formation of a novel class of linear invadosomes

Title	Physiological type I collagen organization induces the formation of a novel class of linear invadosomes
Publication Type	Journal Article
Year of Publication	2012
Authors	Juin, A, Billottet C, Moreau V, Destaing O, Albiges-Rizo C, Rosenbaum J, Genot E, Saltel F
Journal	Molecular Biology of the Cell
Volume	23
Pagination	297-309
ISSN	1059-1524
Abstract	Invadosomes are F-actin structures able to degrade the matrix through the activation of matrix metalloproteases. As fibrillar type I collagen promotes pro-MMP2 activation by MT1-MMP, we aimed at investigating the functional relationships between collagen I organization and invadosomes induction. We found that fibrillar collagen I induced linear F-actin structures, distributed along the fibrils, on endothelial cells, macrophages, fibroblasts and tumour cells. These structures share features with conventional invadosomes as they express cortactin, N-WASP and accumulate the scaffold protein Tks5, which proved essential for their formation. Based on their ability to degrade extracellular matrix elements and their original architecture, we named these structures linear invadosomes. Interestingly, podosomes or invadopodia were replaced by linear invadosomes upon contact of the cells with fibrillar collagen I. However, linear invadosomes clearly differ from classical invadosomes as they do not contain paxillin, vinculin and β1/β3 integrins. Using knock out MEFs and RGD peptide, we demonstrate that linear invadosome formation and activity are independent of β1 and β3 integrins. Finally, linear invadosomes were also formed in a 3D collagen matrix. This study demonstrates that fibrillar collagen I is the physiological inducer of a novel class of invadosomes.
DOI	10.1091/mbc.E11-07-0594
Short Title	Molecular Biology of the Cell