This week, action potentials (surprising!), in particular in unicellular organisms.

• Mori et al (2006). A Three-Dimensional Model of Cellular Electrical Activity (PhD thesis). Equations for electrodiffusion in 3D (complicated!).
• Rama et al (2015). Presynaptic hyperpolarization induces a fast analogue modulation of spike-evoked transmission mediated by axonal sodium channels. Cool paper from Debanne's lab (funded by our ANR grant!).
• Bhattacharjee et al (2010). A neuron-benign microfluidic gradient generator for studying the response of mammalian neurons towards axon guidance factors. A device to make controlled spatial concentration gradients in a dish.
• Roberts and Mackie (1980). The giant axon escape system of a hydrozoan medusa, Aglantha digitale. Interesting case of a ring-shaped axon of >30 µm.
• Chen et al (2008). Functional properties and differential neuromodulation of Nav1.6 channels. Differences between Nav1.2 and Nav1.6 channels (bottom line: Nav1.6 is good for high-frequency firing).
• Williams and Wozny (2011). Errors in the measurement of voltage-activated ion channels in cell-attached patch-clamp recordings. Not surprising, but still an important methodological point: measuring membrane currents in cell-attached is biased by the depolarization of the cell.
• Slayman et al (1976). “Action potentials” in Neurospora crassa, a mycelial fungus. Action potentials everywhere!
• Kamada (1934). Some Observations on Potential Differences Across the Ectoplasm Membrane of Paramecium. First measurement of resting membrane potential in Paramecium and the dependence on ions (before Hodgkin & Huxley!).
• Young (1936). The structure of nerve fibres in cephalopods and crustacea. “It is important here to notice that [squid giant axons] are not the axons of single cells, but are syncytia produced, in the case of the largest fibres of Loligo, by the fusion of the processes of many hundreds of small cells” (so much for the neuron doctrine!).
• Machemer and Eckert (1973). Electrophysiological Control of Reversed Ciliary Beating in Paramecium. Voltage-clamp study, showing reversal of ciliary beating when depolarization is above a voltage threshold.
• Eckert and Sibaoka (1968). The Flash-Triggering Action Potential of the Luminescent Dinoflagellate Noctiluca. Another unicellular organism, this time the spike triggers a flash of light.
• Febvre-Chevalier et al (1986). Sodium-Calcium Action Potential Associated with Contraction in the Heliozoan Actinocoryne Contractilis. Another unicellular organism with spikes, but this time sodium spikes (rather than calcium spikes in paramecium).
• Kralj et al (2011). Electrical Spiking in Escherichia coli Probed with a Fluorescent Voltage-Indicating Protein. Self-explanatory!
• Masi et al (2015). Electrical spiking in bacterial biofilms. Spikes are really everywhere!
• Ashley and Ridgway (1968). Simultaneous Recording of Membrane Potential, Calcium Transient and Tension in Single Muscle Fibres. The muscular action potential.
• Levin (2014). Molecular bioelectricity - how endogenous voltage potentials control cell behavior and instruct pattern regulation in vivo. Intriguing: intracellular voltage gradients at rest.
• Reid et al (2007). Non-invasive measurement of bioelectric currents with a vibrating probe. To measure extracellular currents around a cell.
• Binggelli and Weinstein (1986). Membrane potentials and sodium channels - Hypotheses for growth regulation and cancer formation based on changes in sodium channels and gap junctions. Shows resting membrane potential is many cell types (not just neurons), and how it differs between mature cells and developing/cancer cells.