Embryonic endothelial evolution towards first hematopoietic stem cells revealed by single-cell transcriptomic and functional analyses.
Siyuan HouZongcheng LiXiaona ZhengYun GaoJi DongYanli NiXiaobo WangYunqiao LiXiaochen DingZhilin ChangShuaili LiYuqiong HuXiaoying FanYu HouLu WenBing LiuFu-Chou TangYu LanPublished in: Cell research (2020)
Hematopoietic stem cells (HSCs) in adults are believed to be born from hemogenic endothelial cells (HECs) in mid-gestational embryos. Due to the rare and transient nature, the HSC-competent HECs have never been stringently identified and accurately captured, let alone their genuine vascular precursors. Here, we first used high-precision single-cell transcriptomics to unbiasedly examine the relevant EC populations at continuous developmental stages with intervals of 0.5 days from embryonic day (E) 9.5 to E11.0. As a consequence, we transcriptomically identified two molecularly different arterial EC populations and putative HSC-primed HECs, whose number peaked at E10.0 and sharply decreased thereafter, in the dorsal aorta of the aorta-gonad-mesonephros (AGM) region. Combining computational prediction and in vivo functional validation, we precisely captured HSC-competent HECs by the newly constructed Neurl3-EGFP reporter mouse model, and realized the enrichment further by a combination of surface markers (Procr+Kit+CD44+, PK44). Surprisingly, the endothelial-hematopoietic dual potential was rarely but reliably witnessed in the cultures of single HECs. Noteworthy, primitive vascular ECs from E8.0 experienced two-step fate choices to become HSC-primed HECs, namely an initial arterial fate choice followed by a hemogenic fate conversion. This finding resolves several previously observed contradictions. Taken together, comprehensive understanding of endothelial evolutions and molecular programs underlying HSC-primed HEC specification in vivo will facilitate future investigations directing HSC production in vitro.
Keyphrases
- single cell
- endothelial cells
- rna seq
- induced apoptosis
- mouse model
- cell cycle arrest
- aortic valve
- spinal cord
- public health
- high glucose
- endoplasmic reticulum stress
- pregnant women
- pulmonary artery
- weight gain
- signaling pathway
- bone marrow
- neuropathic pain
- coronary artery
- crispr cas
- current status
- brain injury
- cerebral ischemia
- aortic dissection