Integrin control of cell cycle: a new role for ubiquitin ligase.

Receptor tyrosine kinases and integrins are activated by growth factors and extracellular matrix, respectively. Their activation leads to signal transduction cascades that control many aspects of cell phenotype, including progression through the G(1) phase of the cell cycle. However, the signalling cassettes driven by growth factors and matrix do not work independently of each other. Integrin triggering is essential to facilitate kinase- and GTPase-mediated signals and thereby drive efficient transfer of information through the growth factor-cyclin axis. A recent study indicates that an additional type of player has a key role in adhesion-regulated control of cell cycle, namely ubiquitin ligase.