Animals depend on sensory feedback from mechanosensory afferents for the dynamic control of movement. This sensory feedback needs to be selectively modulated in a task- and context-dependent manner. Here, we show that inhibitory interneurons (INs) expressing the ROR? orphan nuclear receptor gate sensory feedback to the spinal motor system during walking and are required for the production of a fluid locomotor rhythm. Genetic manipulations that abrogate inhibitory ROR? IN function result in an ataxic gait characterized by exaggerated flexion movements and marked alterations to the step cycle. Inactivation of ROR? in inhibitory neurons leads to reduced presynaptic inhibition and changes to sensory-evoked reflexes, arguing that the ROR? inhibitory INs function to suppress the sensory transmission pathways that activate flexor motor reflexes and interfere with the ongoing locomotor program. VIDEO ABSTRACT.     «

Animals depend on sensory feedback from mechanosensory afferents for the dynamic control of movement. This sensory feedback needs to be selectively modulated in a task- and context-dependent manner. Here, we show that inhibitory interneurons (INs) expressing the ROR? orphan nuclear receptor gate sensory feedback to the spinal motor system during walking and are required for the production of a fluid locomotor rhythm. Genetic manipulations that abrogate inhibitory ROR? IN function result in an at...     »