Regulation of granulopoiesis by transcription factors and cytokine signals

The development of mature granulocytes from hematopoietic precursor cells I s controlled by a myriad of transcription factors which regulate the expres sion of essential genes, including those encoding growth factors and their receptors, enzymes, adhesion molecules, and transcription factors themselve s. In particular, C/EBP alpha, PU.1, CBF, and c-Myb have emerged as critica l players during early granulopoiesis. These transcription factors interact with one another as well as other factors to regulate the expression of a variety of genes important in granulocytic lineage commitment. An important goal remains to understand in greater detail how these various factors act in concert with signals emanating from cytokine receptors to influence the various steps of maturation, from the pluripotent hematopoietic stem cell, to a committed myeloid progenitor, to myeloid precursors, and ultimately t o mature granulocytes.