Satellite glial cells modulate proprioceptive neuron activity in dorsal root ganglia

Proprioception, the sense of body and limb position, is mediated by proprioceptors and is crucial for important motor functions such as standing and walking. Proprioceptor cell bodies reside within the peripheral dorsal root ganglia (DRG) and are tightly enveloped by satellite glial cells (SGCs). SCGs express a number of Gq protein-coupled receptors (Gq GPCRs), but their functional consequences on proprioceptor activity is unknown. Using a combination of chemogenetics, genetics, Ca2+ imaging, pharmacology, immunohistochemistry, and biochemistry, we provide evidence that SGC Gq GPCR signaling is sufficient to drive purinergic receptor-mediated Ca2+ responses in proprioceptor cell bodies. Our findings suggest a potential role for SGC Gq GPCR signaling in shaping proprioceptor information processing. Furthermore, this demonstration of SGC-induced proprioceptor activation has profound implications with SGC Gq GPCR signaling and purinergic receptors representing potential therapeutic targets for alleviating some proprioceptor and sensorimotor impairments associated with spinal muscular atrophy or Friedreichs ataxia.