Postnatal Pax7-expressing limb cells are multipotent and generate non-myogenic lineages that persist into adulthood.

Postnatal Pax7-expressing limb cells are multipotent and generate non-myogenic lineages, including fibro-adipogenic progenitors, that persist into adulthood, with significant implications for muscle regeneration.

• Why it matters: Understanding the plasticity of Pax7+ cells during postnatal development addresses gaps in knowledge about muscle growth and regeneration, which could inform treatments for muscle injuries and degenerative diseases.
• What they did: Lineage tracing in neonatal mice revealed that Pax7+ cells produce diverse lineages, including a novel Pax7 FAP subpopulation, with Notch signaling influencing their fate; long-term studies confirmed their persistence and regenerative potential.
• The result: Neonatal Pax7+ cells contribute to non-myogenic lineages into adulthood, and adult muscle injury induces the formation of proliferative Pax7 FAPs, enhancing regenerative capacity and revealing new cellular targets for therapy.