Fluorescence deconvolution light micrograph of a neonatal cardiomyocyte (heart cell) stained to highlight actin fibres (green) and the protein vinculin (red). Actin is part of the cytoskeleton. The cytoskeleton maintains the cell's shape, allows some cellular mobility and is involved in intracellular transport. Vinculin is a membrane-cytoskeletal protein that is present at focal adhesions, where the cytoskeleton connects to the extracellular matrix.