Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, 510515 Guangzhou, China.
Guangdong Technology and Engineering Research Center for Molecular Diagnostics of Human Genetic Diseases, 510515 Guangzhou, China.
Proc Natl Acad Sci U S A. 2020 Jun 9;117(23):12868-12876. doi: 10.1073/pnas.1915085117. Epub 2020 May 26.
Fine-resolution differentiation trajectories of adult human hematopoietic stem cells (HSCs) involved in the generation of red cells is critical for understanding dynamic developmental changes that accompany human erythropoiesis. Using single-cell RNA sequencing (scRNA-seq) of primary human terminal erythroid cells (CD34CD235a) isolated directly from adult bone marrow (BM) and umbilical cord blood (UCB), we documented the transcriptome of terminally differentiated human erythroblasts at unprecedented resolution. The insights enabled us to distinguish polychromatic erythroblasts (PolyEs) at the early and late stages of development as well as the different development stages of orthochromatic erythroblasts (OrthoEs). We further identified a set of putative regulators of terminal erythroid differentiation and functionally validated three of the identified genes, , , and , by monitoring cell differentiation and apoptosis. We documented that knockdown of suppressed the commitment of HSCs to erythroid lineage and cell proliferation and delayed differentiation of colony-forming unit-erythroid (CFU-E) to the proerythroblast stage (ProE). In contrast, the knockdown of and delayed differentiation of PolyE to OrthoE stage. Taken together, the convergence and divergence of the transcriptional continuums at single-cell resolution underscore the transcriptional regulatory networks that underlie human fetal and adult terminal erythroid differentiation.
精确区分参与红细胞生成的成人造血干细胞（HSCs）的分化轨迹，对于理解伴随人类红细胞生成的动态发育变化至关重要。我们通过对直接从成人骨髓（BM）和脐血（UCB）分离的终末红细胞（CD34CD235a）进行单细胞 RNA 测序（scRNA-seq），以空前的分辨率记录了终末分化的人类成红细胞的转录组。这些见解使我们能够区分早期和晚期多色性成红细胞（PolyE）以及正染性成红细胞（OrthoE）的不同发育阶段。我们进一步确定了一组潜在的终末红细胞分化调节剂，并通过监测细胞分化和细胞凋亡，对其中的三个基因、、和进行了功能验证。我们记录到，下调会抑制 HSCs 向红细胞系的定向分化和细胞增殖，并延迟集落形成单位-红细胞（CFU-E）向原红细胞阶段（ProE）的分化。相比之下，下调和会延迟 PolyE 向 OrthoE 阶段的分化。总之，单细胞分辨率下转录连续体的趋同和分歧突出了人类胎儿和成人终末红细胞分化的转录调控网络。
