Global chromatin accessibility profiling analysis reveals a chronic activation state in aged muscle stem cells
Anqi Dong,
Jing Liu,
Kangning Lin,
Wenshu Zeng,
Wai-Kin So,
Shenyuan Hu,
Tom H. Cheung
Affiliations
Anqi Dong
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Jing Liu
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Kangning Lin
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Wenshu Zeng
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Wai-Kin So
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Shenyuan Hu
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China
Tom H. Cheung
Division of Life Science, Center for Stem Cell Research, HKUST-Nan Fung Life Sciences Joint Laboratory, State Key Laboratory of Molecular Neuroscience, Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong Center for Neurodegenerative Diseases, Hong Kong, China; Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, Shenzhen-Hong Kong Institute of Brain Science, HKUST Shenzhen Research Institute, Shenzhen, China; Corresponding author
Summary: Regulation of chromatin accessibility is critical for cell fate decisions. Chromatin structure responds to extrinsic environments rapidly. The traditional adult stem cell isolation approach requires tissue dissociation, which triggers stem cell activation and leads to alterations in chromatin structure. To preserve the in vivo chromatin states, we utilized the PFA-perfusion-based isolation approach and characterized the DNA regulatory landscapes during muscle stem cell quiescence exit and aging. We showed that aged SCs display a chronically activated chromatin signature. Detailed analysis of the chromatin accessibility profiles identified key enhancer elements for SC quiescence. Constant activation of the enhancer elements promotes stemness and prevents SCs from differentiation, whereas genetic deletion causes cell-cycle arrest and leads to defects in activation. Our comprehensive characterization of the chromatin accessibility and transcriptomic landscapes in SC quiescence and aging broadens our understanding of these processes and identifies key distal regulatory elements for SC function.
