Sema3a-Nrp1 Signaling Mediates Fast-Twitch Myofiber Specificity of Tw2⁺ Cells.

ABSTRACT: We previously identified a unique population of interstitial muscle progenitors, marked by expression of the Twist2 transcription factor, which fuses specifically to type IIb/x fast-twitch myofibers. Tw2⁺ progenitors are distinct from satellite cells, a muscle progenitor that expresses Pax7 and contributes to all myofiber types. Through RNA sequencing and immunofluorescence, we identify the membrane receptor, Nrp1, as a marker of Tw2⁺ cells but not Pax7⁺ cells. We also found that Sema3a, a chemorepellent ligand for Nrp1, is expressed by type I and IIa myofibers but not IIb myofibers. Using stripe migration assays, chimeric cell-cell fusion assays, and a Sema3a transgenic mouse model, we identify Sema3a-Nrp1 signaling as a major mechanism for Tw2⁺

SUBMITTER: Li S 

PROVIDER: S-EPMC6783380 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature