Biochemistry 2007

Upper left panel, Electrical signals are recorded from a Xenopus oocyte expressing the circadian photoreceptor melanopsin in response to illumination with blue light. Upper right panel, Photocurrent recorded from an oocyte expressing melanopsin and the TRPC3 ion channel in response to illumination at various wavelengths. Peak activation of melanopsin signaling occurs at about 470 nm, which corresponds to the peak light sensitivity of the circadian system. Lower left panel, Expression of the subthreshold potassium channel Elk2 in the soma and dendrites of cerebellar Purkinje neurons. Elk potassium channels are active at neuronal resting potentials and thus may have a strong influence on neuronal excitation. Lower right panel, Elk1 currents recorded from an inside-out patch in symmetrical potassium. Work done in the laboratory of Timothy Jegla, Ph.D., assistant professor, California campus.