Early events in M-CSF receptor signaling

The hl-CSF receptor (M-CSFR) is expressed in monocytes-macrophages and thei r progenitors, and drives growth and development of this blood cell lineage . The M-CSFR is a member of a small family of growth factor receptors exhib iting related structures but distinct tissue-specific functions. This revie w discusses the early molecular events in the M-CSF signaling mechanisms, p ositive signals, negative signals, the possible organization of individual signaling pathways, and the problem of achieving specificity in the signal transduction mechanism.