FoxO maintains a genuine quiescent muscle stem-cell state until geriatric age (ATAC-seq)

We identify two quiescent stem-cell states through relative CD34 expression: CD34High, with stemness properties (genuine state), and CD34Low, more committed to myogenic differentiation (primed state). The genuine-quiescent state is preserved into later life succumbing only in extreme old age due to acquisition of primed-state traits. We identified niche-derived IGF1-dependent Akt activation as detrimental to the genuine stem-cell state by imposing primed-state features via FoxO inhibition. Interventions to neutralize Akt and promote FoxO activity drive primed-to-genuine state conversion, while FoxO inactivation deteriorates the genuine state at young age, causing muscle regenerative failure, as in geriatric mice. Muscles from mice were mechanically disaggregated and dissociated in Ham’s F10 media containing Liberase (0.1mg/g muscle weight) (Roche; 5mg/mL) and Dispase 0.3% at 37 °C for 2 h and then filtered. Cells were then incubated in lysis buffer (BD Pharm Lyse) for 10 min on ice, re-suspended in PBS with 2% goat serum (FACS buffer) and counted. PE-Cy7-conjugated anti-CD45 (Biolegend 103114), anti-Sca-1 (Biolegend 108114) and PE-Cy7-conjugated anti-CD31 (Biolegend 102418) antibodies were used for lineage-negative selection. PE-conjugated anti-α7-integrin (AbLab AB10STMW215) and Alexa Fluor 647-conjugated anti-CD34 (BD Pharmigen 560230) were used for double positive staining of quiescent satellite cells. Satellite cells were sorted using a FACS Aria II (BD) and processed for RNA-seq and ATAC-seq. This dataset includes the 26 ATAC-Seq samples of this project.