Signal transduction and cellular radiation responses

Exposure of cells to ionizing radiation results in complex cellular respons es resulting in cell death and altered proliferation states, The underlying cytotoxic, cytoprotective and cellular stress responses to radiation are m ediated by existing signaling pathways, activation of which may be amplifie d by intrinsic cellular radical production systems. These signaling respons es include the activation of plasma membrane receptors, the stimulation of cytoplasmic protein kinases, transcriptional activation, and altered cell c ycle regulation. From the data presented, there is increasing evidence for the functional links between cellular signal transduction responses and DNA damage recognition and repair, cell survival, or cell death through apopto sis or reproductive mechanisms. (C) 2000 by Radiation Research Society.