Cover photograph (Copyright © 2007, American Society for Microbiology. All Rights Reserved.): RACK1 regulates active extracellular signal-regulated kinase (ERK) targeting to focal adhesions and focal adhesion disassembly. REF52 fibroblasts were transfected with control (upper) or RACK1-specific (lower) small interfering RNA, stained using an antibody against active ERK (red) and paxillin (green), and examined by immunofluorescence microscopy. In the control cells, active ERK localizes to focal adhesions (yellow) while downregulation of RACK1 results in the absence of active ERK in focal adhesions. The absence of active ERK in focal adhesions slows down focal adhesion disassembly, which results in the increase in focal adhesion number. (See related article on page 8296.)