Autophagy in hematopoietic stem cell development of the embryo.

Hematopoietic stem cells (HSC) emerge from hemogenic endothelial cells (HEC) in the aorta-gonad-mesonephros (AGM) region of embryos, which go through the pre-HSC process. Various intrinsic and extrinsic factors are involved in this process. We recently discovered that the existence of distinct macroautophagic/autophagic statuses in hematopoietic precursors is related to the hematopoietic potential of pre-HSCs and the depletion of the (autophagy related 5) gene specifically in endothelial cells impaired in the transition of endothelial to pre-HSCs, by hampering the autophagic process, likely via the NCL (nucleolin) pathway. Atg5: autophagy related 5; EGFP: enhanced green fluorescent protein; EHT: endothelial-to-hematopoietic transition; HEC: hemogenic endothelial cell; HSC: hematopoietic stem cell; NCL: nucleolin; RFP: red fluorescent protein.