MS and GTO proprioceptor subtypes in the molecular genetic era: Opportunities for new advances and perspectives

Proprioceptive feedback from skeletal muscle is an integral element of motor control, yet the precise physiological roles of muscle spindle (MS) and Golgi tendon organ (GTO) sensory receptors have remained difficult to disentangle due to technical limitations. New insights into the molecular basis of MS and GTO afferent subtypes offers genetic opportunities to further our understanding of the distinct functional features of these proprioceptor classes, while at the same time revealing additional layers of complexity in the regulation of coordinated motor output.