Fig. 4

Spectral sensitivities of opsin-based pigments determined by GloSensor cAMP-dependent luciferase reporter assay. a, b The sensitivities of Gq-rhodopsin and xenopsin were determined by HAS, based on the light-induced increase in the intracellular cAMP concentration ([cAMP]_i), using chimeric opsin containing the intracellular domain of Gs-coupled jellyfish opsin. The sensitivity curve of each opsin was estimated by fitting the sensitivity values with a template of the rhodopsin spectrum (i.e., rhodopsin nomogram). c, d The relative amplitudes of the Opn5A and Opn5B responses were determined by the decrease in the [cAMP]_i in the cultured cells expressing wild-type Opn5A or Opn5B. Upper traces are examples of light-dependent changes in the relative [cAMP]_i levels. Error bars: ± SE (n = 3)