Adult skeletal muscles are maintained during homeostasis and regenerated upon injury by muscle stem cells (MuSCs). A heterogeneity in self-renewal, differentiation and regeneration properties has been reported for MuSCs based on their anatomical location. Although MuSCs derived from extraocular muscles (EOM) have a higher regenerative capacity than those derived from limb muscles, the molecular determinants that govern these differences remain undefined. Here we show that EOM and limb MuSCs have distinct DNA methylation signatures associated with enhancers of location-specific genes, and that the EOM transcriptome is reprogrammed following transplantation into a limb muscle environment. Notably, EOM MuSCs expressed host-site specific positional Hox codes after engraftment and self-renewal within the host muscle. However, about 10% of EOM-specific genes showed engraftment-resistant expression, pointing to cell-intrinsic molecular determinants of the higher engraftment potential of EOM MuSCs. Our results underscore the molecular diversity of distinct MuSC populations and molecularly define their plasticity in response to microenvironmental cues. These findings provide insights into strategies designed to improve the functional capacity of MuSCs in the context of regenerative medicine.

成体骨骼肌在稳态过程中得以维持，并在肌肉干细胞 (MuSC) 损伤后再生。据报道，MuSC 根据其解剖位置，在自我更新、分化和再生特性方面存在异质性。尽管源自眼外肌（EOM）的 MuSC 比源自肢体肌肉的 MuSC 具有更高的再生能力，但控制这些差异的分子决定因素仍不清楚。在这里，我们表明 EOM 和肢体 MuSC 具有与位置特异性基因增强子相关的独特 DNA 甲基化特征，并且 EOM 转录组在移植到肢体肌肉环境中后会被重新编程。值得注意的是，EOM MuSC 在宿主肌肉内植入和自我更新后表达宿主位点特定位置的Hox代码。然而，约 10% 的 EOM 特异性基因表现出植入抗性表达，表明 EOM MuSC 具有较高植入潜力的细胞内在分子决定因素。我们的结果强调了不同 MuSC 群体的分子多样性，并从分子上定义了它们响应微环境线索的可塑性。这些发现为在再生医学背景下旨在提高 MuSC 功能的策略提供了见解。