TY - JOUR TI - Long ascending propriospinal neurons provide flexible, context-specific control of interlimb coordination AU - Pocratsky, Amanda M AU - Shepard, Courtney T AU - Morehouse, Johnny R AU - Burke, Darlene A AU - Riegler, Amberley S AU - Hardin, Josiah T AU - Beare, Jason E AU - Hainline, Casey AU - States, Gregory JR AU - Brown, Brandon L AU - Whittemore, Scott R AU - Magnuson, David SK A2 - Calabrese, Ronald L A2 - Bui, Tuan V VL - 9 PY - 2020 DA - 2020/09/09 SP - e53565 C1 - eLife 2020;9:e53565 DO - 10.7554/eLife.53565 UR - https://doi.org/10.7554/eLife.53565 AB - Within the cervical and lumbar spinal enlargements, central pattern generator (CPG) circuitry produces the rhythmic output necessary for limb coordination during locomotion. Long propriospinal neurons that inter-connect these CPGs are thought to secure hindlimb-forelimb coordination, ensuring that diagonal limb pairs move synchronously while the ipsilateral limb pairs move out-of-phase during stepping. Here, we show that silencing long ascending propriospinal neurons (LAPNs) that inter-connect the lumbar and cervical CPGs disrupts left-right limb coupling of each limb pair in the adult rat during overground locomotion on a high-friction surface. These perturbations occurred independent of the locomotor rhythm, intralimb coordination, and speed-dependent (or any other) principal features of locomotion. Strikingly, the functional consequences of silencing LAPNs are highly context-dependent; the phenotype was not expressed during swimming, treadmill stepping, exploratory locomotion, or walking on an uncoated, slick surface. These data reveal surprising flexibility and context-dependence in the control of interlimb coordination during locomotion. KW - spinal cord KW - long ascending propriospinal neurons KW - locomotor circuitry KW - central pattern generator KW - synaptic silencing JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -