On the Cover
The image shows a Src-transformed fibroblast with highly invasive structures known as podosomes or invadopodia. The podosomes appear yellow after co-staining for F-actin (red) and phosphorylated cortactin tyrosine-421 (green). Larger podosome structures and enhanced capacities for cell invasion and metastasis are associated with tyrosine phosphorylation of the docking protein CAS (Crk-associated substrate). See article by Brábek et al. on page 307.