| Abstrakt: |
The haematopoietic system is established early during embryonic development and is maintained throughout adult life by haematopoietic stem cells. The cellular intermediates leading to the formation of mature blood cells are now fairly well characterised; from the mesoderm germ layer, successive steps of commitment give rise to haemangioblast, haemogenic endothelium, and haematopoietic stem and progenitor cells. Key transcription factors, such as ETV2, SCL, GATA2 or RUNX1, have been shown to specifically control some of these cell fate decisions. However, an integrated view of the transcriptional network controlling haematopoietic specification still remains to be established. Furthermore, it has become clear over the last decade that the transcriptional control of cell fate specification is globally regulated by epigenetic mechanisms. While the chromatin landscape is starting to be unravelled in adult haematopoiesis, virtually nothing is known about the epigenetic processes regulating the onset of haematopoiesis in the developing embryo. In this chapter, we describe the current state of our knowledge on the onset of mammalian haematopoiesis, focusing on murine development as it is by far the best characterised organism. [ABSTRACT FROM AUTHOR] |
