The molecular foundation of proprioceptor muscle-type identity

Abstract

The precise execution of coordinated movements depends on proprioception, the sense of body position in space. However, the molecular underpinnings of proprioceptive neuron subtype identities are not clear yet. In this study, we searched for molecular correlates of proprioceptor subtypes defined according to the identity of the muscle they innervate. We identified and validated signatures for subtypes monitoring the activity of back, abdominal, and hindlimb muscles. We found that proprioceptor muscle identity is acquired early in development and comprise programs controlling wiring specificity. Altogether this work paves the way for defining the mechanisms underlying the development of proprioceptor subtypes to the single muscle level and dissect their contributions to motor control.