Intracellular mediators of c-fos induction.

Abstract

Transcription of the c-fos proto-oncogene is rapidly and transiently induced in cells exposed to a remarkably wide range of external stimuli, including growth and differentiation factors, neurotransmitters, drugs, and mechanical stimuli (for review, see Curran 1988). These diverse agents act on cells through a series of divergent signal transduction pathways. Activation of many of these pathways triggers c-fos transcription. These pathways include those involving protein kinase C, calcium, and cAMP. Our work concerns the molecular mechanisms through which extracellular signals are communicated to the c-fos gene. Here, we report on our efforts to identify cis-acting c-fos sequences responsive to distinct intracellular signaling pathways, the identification of cellular DNA-binding proteins that interact with these sequences, and the use of microinjection to dissect and block individual signaling pathways that act on the c-fos gene.