A single-nucleus chromatin accessibility atlas reveals epigenetic dynamics in aging mouse skeletal muscle.

Authors

Juan An, Guangyao Lai, Jing Zuo, Jianwen Yuan, Lixin Fu, Bo Zhang, Xiao Zhang, Yuan Lv, Pengcheng Guo, Dajiang Qin, Miguel A Esteban, Yancheng Song, Yiwei Lai

Published in

The FEBS journal. Aug 03, 2026. Epub Aug 03, 2026.

Abstract

Skeletal muscle undergoes a progressive decline in mass and function with aging, a condition that in its extreme form is known as sarcopenia. This is driven by complex cellular and molecular alterations, such as shifts in myonucleus composition, increased fibrosis, and fat or immune cell infiltration. Despite extensive research, effective therapeutic interventions for sarcopenia remain limited. Recent advances in single-cell omics technologies have begun to unravel the cellular and molecular heterogeneity of mouse and human skeletal muscle across the lifespan, identifying age-enriched cell states and dynamic transcriptional changes. However, epigenetic regulation during skeletal muscle aging is less well characterized. To help address this gap, we performed single-nucleus Assay for Transposase-Accessible Chromatin using sequencing (snATAC-seq) on skeletal muscle from young adult and aged male mice, generating chromatin accessibility profiles from over 43,000 nuclei. Among other findings, our analyses reveal an age-enriched pro-atrophy subpopulation of type IIb myonuclei marked by increased chromatin accessibility at the Ampd3 locus. Furthermore, we delineate the epigenetic mechanisms underlying the transition of healthy type IIb myonuclei into Ampd3⁺ myonuclei, revealing key chromatin remodeling events that drive this phenotypic shift. Moreover, by integrating with an existing single-nucleus RNA sequencing dataset of the same anatomical origin, we identified thousands of cell-type-specific cis-regulatory elements related to aging programs. Within these elements, we observed a broad depletion of binding motifs for transcription factors with roles in cellular identity and muscle regeneration, concomitant with the gain of stress-responsive transcription factors. Our work helps understand the epigenetic events underlying mammalian skeletal muscle aging.

PMID:
42545094
Bibliographic data and abstract were imported from PubMed on 03 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.