%0 Journal Article %A Shangbang Gao %A Sihui Guan %A Anthony D. Fouad %A Jun Meng %A Yung-Chi Huang %A Yi Li %A Salvador Alcaire %A Wesley Hung %A Taizo Kawano %A Yangning Lu %A Yingchuan Billy Qi %A Yishi Jin %A Mark Alkema %A Christopher Fang-Yen %A Mei Zhen %T Excitatory Motor Neurons Function as Central Pattern Generators in an Anatomically Compressed Motor Circuit for Reverse Locomotion %D 2017 %R 10.1101/135418 %J bioRxiv %P 135418 %X Central pattern generators are cell- or network-driven oscillators that underlie motor rhythmicity. The existence and identity of C. elegans CPGs are unknown. Through cell ablation, electrophysiology, and calcium imaging, we identified oscillators for C. elegans reverse locomotion. We show that the cholinergic and excitatory class A motor neurons exhibit intrinsic and oscillatory activity, and such an activity can drive reverse locomotion without premotor interneurons. Regulation of their oscillatory activity, either through effecting the P/Q/N high voltage-activated calcium channel, an endogenous constituent of their intrinsic oscillation, or, via the dual regulation by descending premotor interneurons, determines the propensity, velocity, and sustention of reverse locomotion. Thus, the reversal motor neuron themselves serve as distributed local oscillators; regulation of their intrinsic activity controls the reversal motor state. These findings exemplify anatomic and functional compression: motor executors integrate the role of rhythm generation in a locomotor network that is constrained by small cell numbers.HighlightsThe class A motor neurons (A-MNs) intrinsically oscillate.High voltage-activated calcium channel is a constituent of A-MN oscillation.Regulation of A-MN oscillation by interneurons determines the reversal state.A-MNs integrate the role of multiple neuron types in large locomotor networks. %U https://www.biorxiv.org/content/biorxiv/early/2017/05/08/135418.full.pdf