PT  - JOURNAL ARTICLE
AU  - Tianqi Xu
AU  - Jing Huo
AU  - Shuai Shao
AU  - Michelle Po
AU  - Taizo Kawano
AU  - Yangning Lu
AU  - Min Wu
AU  - Mei Zhen
AU  - Quan Wen
TI  - A descending pathway facilitates undulatory wave propagation in <em>Caenorhabditis elegans</em> through gap junctions
AID  - 10.1101/131490
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 131490
4099  - http://biorxiv.org/content/early/2017/07/23/131490.short
4100  - http://biorxiv.org/content/early/2017/07/23/131490.full
AB  - Descending signals from the brain play critical roles in controlling and modulating locomotion kinematics. In the Caenorhabditis elegans nervous system, descending AVB premotor interneurons exclusively form gap junctions with B-type motor neurons that drive forward locomotion. We combined genetic analysis, optogenetic manipulation, and computational modeling to elucidate the function of AVB-B gap junctions during forward locomotion. First, we found that some B-type motor neurons generated intrinsic rhythmic activity, constituting distributed central pattern generators. Second, AVB premotor interneurons drove bifurcation of B-type motor neuron dynamics, triggering their transition from stationary to oscillatory activity. Third, proprioceptive couplings between neighboring B-type motor neurons entrained the frequency of body oscillators, forcing coherent propagation of bending waves. Despite substantial anatomical differences between the worm motor circuit and those in higher model organisms, we uncovered converging computational principles that govern coordinated locomotion.