An Imbalancing Act: Gap Junctions Reduce the Backward Motor Circuit Activity to Bias C. elegans for Forward Locomotion

Alkema, 2005, Tyramine Functions independently of octopamine in the Caenorhabditis elegans nervous system, Neuron, 46, 247, 10.1016/j.neuron.2005.02.024 Altun, 2009, High resolution map of Caenorhabditis elegans gap junction proteins, Dev. Dyn., 238, 1936, 10.1002/dvdy.22025 Barnes, 1997, The Caenorhabditis elegans avermectin resistance and anesthetic response gene unc-9 encodes a member of a protein family implicated in electrical coupling of excitable cells, J. Neurochem., 69, 2251, 10.1046/j.1471-4159.1997.69062251.x Ben Arous, 2010, Automated imaging of neuronal activity in freely behaving Caenorhabditis elegans, J. Neuroscience Methods, 187, 229, 10.1016/j.jneumeth.2010.01.011 Bennett, 2004, Electrical coupling and neuronal synchronization in the Mammalian brain, Neuron, 41, 495, 10.1016/S0896-6273(04)00043-1 Brenner, 1974, The genetics of Caenorhabditis elegans, Genetics, 77, 71, 10.1093/genetics/77.1.71 Chalfie, 1985, The neural circuit for touch sensitivity in Caenorhabditis elegans, J. Neurosci., 5, 956, 10.1523/JNEUROSCI.05-04-00956.1985 Chen, 2006, Wiring optimization can relate neuronal structure and function, Proc. Natl. Acad. Sci. USA, 103, 4723, 10.1073/pnas.0506806103 Chronis, 2007, Microfluidics for in vivo imaging of neuronal and behavioral activity in Caenorhabditis elegans, Nat Methods, 4, 727, 10.1038/nmeth1075 Crone, 2008, Genetic ablation of V2a ipsilateral interneurons disrupts left-right locomotor coordination in mammalian spinal cord, Neuron, 60, 70, 10.1016/j.neuron.2008.08.009 Getting, 1989, Emerging principles governing the operation of neural networks, Annu. Rev. Neurosci., 12, 185, 10.1146/annurev.ne.12.030189.001153 Giaume, 1983, Bidirectional transmission at the rectifying electrotonic synapse: a voltage-dependent process, Science, 220, 84, 10.1126/science.6298940 Goulding, 2009, Circuits controlling vertebrate locomotion: moving in a new direction, Nat. Rev. Neurosci., 10, 507, 10.1038/nrn2608 Gray, 2005, A circuit for navigation in Caenorhabditis elegans, Proc. Natl. Acad. Sci. USA, 102, 3184, 10.1073/pnas.0409009101 Kerr, 2000, Optical imaging of calcium transients in neurons and pharyngeal muscle of C. elegans, Neuron, 26, 583, 10.1016/S0896-6273(00)81196-4 Kunkel, 2000, Mutants of a temperature-sensitive two-P domain potassium channel, J. Neurosci., 20, 7517, 10.1523/JNEUROSCI.20-20-07517.2000 Lanuza, 2004, Genetic identification of spinal interneurons that coordinate left-right locomotor activity necessary for walking movements, Neuron, 42, 375, 10.1016/S0896-6273(04)00249-1 Leifer, 2011, Optogenetic manipulation of neural activity in freely moving Caenorhabditis elegans, Nat. Methods, 8, 147, 10.1038/nmeth.1554 Liu, 2006, Low conductance gap junctions mediate specific electrical coupling in body-wall muscle cells of Caenorhabditis elegans, J. Biol. Chem., 281, 7881, 10.1074/jbc.M512382200 Macosko, 2009, A hub-and-spoke circuit drives pheromone attraction and social behaviour in C. elegans, Nature, 458, 1171, 10.1038/nature07886 Marder, 2005, Invertebrate central pattern generation moves along, Curr. Biol., 15, R685, 10.1016/j.cub.2005.08.022 Miyawaki, 1997, Fluorescent indicators for Ca2+ based on green fluorescent proteins and calmodulin, Nature, 388, 882, 10.1038/42264 Nagel, 2005, Light activation of channelrhodopsin-2 in excitable cells of Caenorhabditis elegans triggers rapid behavioral responses, Curr. Biol., 15, 2279, 10.1016/j.cub.2005.11.032 Nusbaum, 2002, A small-systems approach to motor pattern generation, Nature, 417, 343, 10.1038/417343a Phelan, 2008, Molecular mechanism of rectification at identified electrical synapses in the Drosophila giant fiber system, Curr. Biol., 18, 1955, 10.1016/j.cub.2008.10.067 Pierce-Shimomura, 1999, The fundamental role of pirouettes in Caenorhabditis elegans chemotaxis, J. Neurosci., 19, 9557, 10.1523/JNEUROSCI.19-21-09557.1999 Pierce-Shimomura, 2008, Genetic analysis of crawling and swimming locomotory patterns in C. elegans, Proc. Natl. Acad. Sci. USA, 105, 20982, 10.1073/pnas.0810359105 Pirri, 2009, A tyramine-gated chloride channel coordinates distinct motor programs of a Caenorhabditis elegans escape response, Neuron, 62, 526, 10.1016/j.neuron.2009.04.013 Rela, 2004, Gap junctions: their importance for the dynamics of neural circuits, Mol. Neurobiol., 30, 341, 10.1385/MN:30:3:341 Starich, 1993, Molecular and genetic analysis of unc-7, a Caenorhabditis elegans gene required for coordinated locomotion, Genetics, 133, 527, 10.1093/genetics/133.3.527 Starich, 2009, Interactions between innexins UNC-7 and UNC-9 mediate electrical synapse specificity in the Caenorhabditis elegans locomotory nervous system, Neural Dev., 4, 16, 10.1186/1749-8104-4-16 Stirman, 2011, Real-time multimodal optical control of neurons and muscles in freely behaving Caenorhabditis elegans, Nat. Methods, 8, 153, 10.1038/nmeth.1555 White, 1976, The structure of the ventral nerve cord of Caenorhabditis elegans, Philos. Trans. R. Soc. Lond. B Biol. Sci., 275, 327, 10.1098/rstb.1976.0086 Wicks, 1996, A dynamic network simulation of the nematode tap withdrawal circuit: predictions concerning synaptic function using behavioral criteria, J. Neurosci., 16, 4017, 10.1523/JNEUROSCI.16-12-04017.1996 Yeh, 2009, Caenorhabditis elegans innexins regulate active zone differentiation, J. Neurosci., 29, 5207, 10.1523/JNEUROSCI.0637-09.2009 Zhang, 2008, V3 spinal neurons establish a robust and balanced locomotor rhythm during walking, Neuron, 60, 84, 10.1016/j.neuron.2008.09.027 Zheng, 1999, Neuronal control of locomotion in C. elegans is modified by a dominant mutation in the GLR-1 ionotropic glutamate receptor, Neuron, 24, 347, 10.1016/S0896-6273(00)80849-1