Fluorescent Labeling Techniques for Investigation of Fibronectin Fibrillogenesis (Labeling Fibronectin Fibrillogenesis)

Department of Cytology, Histology and Embryology, University of Sofia, 1164, Sofia, Bulgaria.
Methods in Molecular Biology (Impact Factor: 1.29). 02/2009; 522:261-74. DOI: 10.1007/978-1-59745-413-1_18
Source: PubMed


Fibronectin fibrillogenesis is a cell-mediated, step-wise process that converts soluble fibronectin into insoluble fibronectin matrix. The deposition of fibronectin fibrils occurs at specific sites on the cell surface and depends on the unfolding of the fibronectin dimer. Fibronectin matrix provides positional information for cell migration during early embryogenesis and plays an important role in cell growth, differentiation, survival, and oncogenic transformation. Here we present simple techniques, based on the use of fluorescently labeled fibronectin and species-specific antifibronectin antibodies that allow determination of the fibronectin fibril growth in conventional in vitro cell cultures and in three-dimensional matrix environment.

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    • "In fixed tissues or fibrillar matrices, extracellular matrix proteins such as fibronectin or fibrin can be also be fluorescently labeled and imaged using standard wide-field or confocal microscopy [72] [77] [78]. For dynamic studies of cell-induced ECM organization, pre-labeled ECM proteins can be used, such as Rhodamine-conjugated fibronectin [78] [79]. However, as detailed below, the most powerful methods for visualizing collagen matrix fibrils are differential interference contrast (DIC), confocal reflection microscopy and second harmonic generation imaging. "
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