Versatile roles of transcription factor PU.1 in hematopoiesis

In my work, I studied the involvement of the PU.1/spi1 gene in mouse hematopoiesis. This gene encodes a transcription factor, which is a central player in the genetic control of the hematopoietic system. My results revealed a new function for PU.1 in erythroid precursors. Moreover, the analysis of the regulation of its expression in the whole hematopoietic system shows that this factor is regulated in a very dynamic way, involving important functions in particular in precursor cells. The PU.1 transcription factor is now found to play a role in all compartments of the hematopoietic system - in stem cells, in lineage-specific progenitors, and in mature cells of the system. Moreover, its functions now appear, in part thanks to my studies, to be very versatile. Thus, PU.1 can induce differentiation, promote cell renewal or act as a pro- or anti-apoptotic factor, depending on the cell type considered.