A novel c-Src recruitment pathway from the cytosol to focal adhesions

The role of myristoylation in the localization and catalytic activity of Src at focal adhesions was investigated by live-cell imaging and site-directed mutagenesis. Although the majority of activated Src molecules are localized at focal adhesions, it is unclear how activated Src molecules are recruited to focal adhesions. Because Src is activated at the cell membrane, translocation of Src to cell membranes is considered to be essential for its recruitment to focal adhesions. Membrane-targeting-deficient Src mutant SrcG2A localizes at focal adhesions, indicating direct recruitment of Src from cytosol to focal adhesions. Furthermore, directly recruited Src molecules are shown to enhance paxillin dynamics at focal adhesions. These results reveal that the regulation of Src activation and translocation is more complex than previously suggested.