Editors' ChoiceSensory Perception

Seeing Is Believing

Science's STKE  01 Aug 2006:
Vol. 2006, Issue 346, pp. tw261
DOI: 10.1126/stke.3462006tw261

In order for vertebrate photoreceptors to exhibit their exquisite sensitivity that allows them to distinguish stimulation by a single photon, the sensor, rhodopsin, must have a very reproducible response. Rhodopsin propagates the signal from absorbed photons by activating transducin, but it is then inactivated by phosphorylation. Doan et al. measured the response of single rhodopsin molecules to single-photon absorption events in preparations of mouse photoreceptors. Multiple phosphorylation events provide independent inhibitory signals that together may provide the remarkable reproducibility of the amplitude and duration of rhodopsin activation observed in the vertebrate eye.

T. Doan, A. Mendez, P. B. Detwiler, J. Chen, F. Rieke, Multiple phosphorylation sites confer reproducibility of the rod's single-photon responses. Science 313, 530-533 (2006). [Abstract] [Full Text]