MicroRNA-127-3p controls murine hematopoietic stem cell maintenance by limiting differentiation
MicroRNA-127-3p controls murine hematopoietic stem cell maintenance by limiting differentiation
复制标题
DOI：
10.3324/haematol.2018.198499
复制
发表时间：
2019-08-31
期刊：
影响因子：
10.1
通讯作者：
Ficara, Francesca
中科院分区：
文献类型：
--
作者：
Crisafulli, Laura;Muggeo, Sharon;Ficara, Francesca
自我更新和分化之间的平衡对于确保造血系统的稳态至关重要，并且是造血干细胞的标志。然而，潜在的分子途径，包括micro-RNA的作用，尚未完全了解。为了评估microRNA的贡献，我们对来自野生型对照和Pbx 1条件性敲除小鼠的造血干细胞及其直接下游后代多能祖细胞进行了microRNA分析，这些小鼠的干细胞显示出严重的自我更新缺陷。无监督的层次聚类分析将干细胞与多能祖细胞分开，表明micro-RNA可能调节成体造血发育的第一个过渡步骤。值得注意的是，Pbx 1缺陷型和野生型细胞分别聚集，将micro-RNA与自我更新障碍联系起来。与对照干细胞相比，在生理干细胞向多能祖细胞转变和Pbx 1缺陷干细胞中micro-RNA的差异表达分析显示miR-127- 3 p的表达差异最大。此外，miR-127- 3 p具有强烈的干细胞特异性，在分化后迅速下调，并且在骨髓造血层级中不再进一步下游重新表达。通过慢病毒海绵载体实现的谱系阴性细胞中miR-127- 3 p功能的抑制导致严重的干细胞耗竭，如用系列移植测定所评估的。miR-127- 3 p海绵状干细胞显示加速分化，其与增殖解偶联，解释了观察到的干细胞减少。谱系阴性细胞中的miR-127- 3 p过表达不改变干细胞池大小，但引起淋巴细胞减少，这可能是由于在干细胞阶段之后缺乏miR-127- 3 p生理下调。因此，miR-127- 3 p的严格调控对于维持造血系统的自我更新干细胞库和稳态至关重要。
The balance between self-renewal and differentiation is crucial to ensure the homeostasis of the hematopoietic system, and is a hallmark of hematopoietic stem cells. However, the underlying molecular pathways, including the role of micro-RNA, are not completely understood. To assess the contribution of micro-RNA, we performed microRNA profiling of hematopoietic stem cells and their immediate downstream progeny multi-potent progenitors from wild-type control and Pbx1-conditional knockout mice, whose stem cells display a profound self-renewal defect. Unsupervised hierarchical cluster analysis separated stem cells from multi-potent progenitors, suggesting that micro-RNA might regulate the first transition step in the adult hematopoietic development. Notably, Pbx1-deficient and wild-type cells clustered separately, linking micro-RNAs to self-renewal impairment. Differential expression analysis of micro-RNA in the physiological stem cell-to-multi-potent progenitor transition and in Pbx1-deficient stem cells compared to control stem cells revealed miR-127-3p as the most differentially expressed. Furthermore, miR-127-3p was strongly stem cell-specific, being quickly down-regulated upon differentiation and not re-expressed further downstream in the bone marrow hematopoietic hierarchy. Inhibition of miR-127-3p function in Lineage-negative cells, achieved through a lentiviral-sponge vector, led to severe stem cell depletion, as assessed with serial transplantation assays. miR-127-3p-sponged stem cells displayed accelerated differentiation, which was uncoupled from proliferation, accounting for the observed stem cell reduction. miR-127-3p overexpression in Lineage-negative cells did not alter stem cell pool size, but gave rise to lymphopenia, likely due to lack of miR-127-3p physiological downregulation beyond the stem cell stage. Thus, tight regulation of miR-127-3p is crucial to preserve the self-renewing stem cell pool and homeostasis of the hematopoietic system.