g., Figure 1E). Goldfish (Carassius auratus) were dark-adapted Vorinostat concentration for 1 hr and killed by decapitation followed immediately by destruction of the brain and spinal cord under Schedule 1 of the UK Animals (Scientific Procedures) Act 1986. Depolarizing bipolar cells were isolated from the retina of goldfish by enzymatic digestion, using methods described by Burrone and Lagnado (1997). The standard Ringer solution contained the following: 110 mM NaCl, 2.5 mM CaCl2, 2.5 mM KCl, 1 mM

MgCl2, 10 mM glucose, and 10 mM HEPES (260 mOsmol l-1, pH 7.3). The solution in the patch pipette to record voltage membrane in current-clamp experiments contained: 110 mM K-gluconate, 4 mM MgCl2, 3 mM Na2ATP, 1 mM Na2GTP, 0.5 mM EGTA, 20 mM HEPES, and 10 mM Na-phosphocreatine (260 mOsmol l-1, pH 7.2). To isolate Ca2+ channel currents, the intracellular solution contained 110 mM Cs-gluconate, 4 mM MgCl2, 3 mM Na2ATP, 1 mM Na2GTP, 10 mM tetraethylammonium chloride, 20 mM HEPES, 0.5 mM EGTA, and 10 mM Na-phosphocreatine (260 mOsmol l-1, pH 7.2). Room temperature solutions were superfused via a fast perfusion system (VC8-S; ALA Scientific). Patch electrodes with 5–7

MΩ tip resistance were pulled from fire-polished borosilicate glass capillary tubes using a micropipette puller (Sutter Instrument). see more The series resistance was typically 8–15 MΩ on rupturing the patch. Holding current in current-clamp configuration was 0 pA. Voltage-clamp and current-clamp recordings were made in synaptic terminals.

In voltage-clamp experiments, the membrane potential was held at −60 mV, and stimuli were delivered by stepping the membrane potential to −10 mV. To construct G/V plots the tail current amplitude measured 0.5 ms after returning to −70 mV was plotted against the preceding voltage step. The voltage dependence of activation was determined from normalized conductance versus voltage curves, which were fitted according to the Boltzmann function: G′=G′max1+exp(V−V1/2k),where G′ is the normalized conductance, V1/2 is the membrane potential at which activation is half-maximal, and k is the slope factor. Signals were recorded using an Axopatch 200A amplifier (Molecular Terminal deoxynucleotidyl transferase Devices), interfaced with an ITC-16 (HEKA) and controlled with Pulse Control 4.3 running under Igor Pro 5 (Wavemetrics). Data were given as the mean ± SEM. We would like to thank all of the members of the Lagnado laboratory for discussions that contributed to this work. We also thank the Wellcome Trust for funding (grant 083220). Experiments were designed by F.E., J.J., J.M.R., and L.L. and performed by F.E., J.J., and J.M.R. Analysis was carried out by F.E., J.J., and L.L. eno2::GCamp3.5 fish were generated and characterized by K.-M.L. The manuscript was written by F.E., J.J., and L.L. “
“Many animals have a diverse repertoire of innate behaviors that can be released by specific sensory stimuli (Tinbergen, 1951).