Highlights
- Single-cell RNA-sequencing identifies cell populations involved in muscle regeneration
- Muscle stem/progenitor cells form a hierarchy with stage-specific regulatory programs
- Bioinformatic analysis identified paracrine factors influencing muscle stem cells
- Syndecan-1/2/4 coordinate paracrine ligand-specific muscle progenitor proliferation
Summary
Muscle regeneration relies on the regulation of muscle stem cells (MuSCs) through paracrine signaling interactions. We analyzed muscle regeneration in mice using single-cell RNA sequencing (scRNA-seq) and generated over 34,000 single-cell transcriptomes spanning four time-points. We identified 15 distinct cell types including heterogenous populations of muscle stem and progenitor cells. We resolved a hierarchical map of these myogenic cells by trajectory inference and observed stage-specific regulatory programs within this continuum. Through ligand-receptor interaction analysis, we identified over 100 candidate regeneration-associated paracrine communication pairs between MuSCs and non-myogenic cells. We show that myogenic stem/progenitor cells exhibit heterogeneous expression of multiple Syndecan proteins in cycling myogenic cells, suggesting that Syndecans may coordinate myogenic fate regulation. We performed ligand stimulation in vitro and confirmed that three paracrine factors (FGF2, TGFβ1, and RSPO3) regulate myogenic cell proliferation in a Syndecan-dependent manner. Our study provides a scRNA-seq reference resource to investigate cell communication interactions in muscle regeneration.
Highlights
1.单细胞RNA测序可识别参与肌肉再生的细胞群
2.肌肉干/祖细胞由于阶段特定的调节程序而分层
3.生物信息学分析确定了影响肌肉干细胞的旁分泌因子
4.Syndecan-1 / 2/4协调旁分泌配体特异性肌肉祖细胞增殖
Summary
肌肉再生依赖于肌肉干细胞（MuSC）的调节，并且需要旁分泌信号的相互作用。我们使用单细胞RNA测序（scRNA-seq）分析了小鼠的肌肉再生，并生成了跨越3个时间点的34,000个单细胞转录组。我们确定了15种不同的细胞类型，包括肌肉干细胞和祖细胞的异质群体。我们通过轨迹推断解决了这些成肌细胞的层次图，并在此连续体内观察到了特定阶段的调节程序。通过配体-受体相互作用分析，我们确定了MuSCs和非肌源性细胞之间的100多个候选再生相关旁分泌通讯对。我们的结果显示，成肌干/祖细胞在循环成肌细胞中表现出多种Syndecan蛋白的异质表达，这表明Syndecans可以协调成肌命运调节。我们在体外进行了配体刺激，并证实了三种旁分泌因子（FGF2，TGFβ1和RSPO3）以Syndecan依赖性方式调节肌原细胞的增殖。我们的研究提供了一个scRNA-seq参考资源来研究肌肉再生中的细胞通讯相互作用。
