Title | Multiple phosphorylation sites confer reproducibility of the rod's single-photon responses. |
Publication Type | Journal Article |
Year of Publication | 2006 |
Authors | Doan T, Mendez A, Detwiler PB, Chen J, Rieke F |
Journal | Science |
Volume | 313 |
Issue | 5786 |
Pagination | 530-3 |
Date Published | 2006 Jul 28 |
ISSN | 1095-9203 |
Keywords | Animals, Arrestin, Electrophysiology, Mice, Mice, Transgenic, Models, Biological, Mutation, Patch-Clamp Techniques, Phosphorylation, Photons, Retinal Rod Photoreceptor Cells, Rhodopsin, Vision, Ocular |
Abstract | Although signals controlled by single molecules are expected to be inherently variable, rod photoreceptors generate reproducible responses to single absorbed photons. We show that this unexpected reproducibility-the consistency of amplitude and duration of rhodopsin activity-varies in a graded and systematic manner with the number but not the identity of phosphorylation sites on rhodopsin's C terminus. These results indicate that each phosphorylation site provides an independent step in rhodopsin deactivation and that collectively these steps tightly control rhodopsin's active lifetime. Other G protein cascades may exploit a similar mechanism to encode accurately the timing and number of receptor activation. |
DOI | 10.1126/science.1126612 |
Alternate Journal | Science |
PubMed ID | 16873665 |
Grant List | EY-02048 / EY / NEI NIH HHS / United States EY-11850 / EY / NEI NIH HHS / United States EY-12155 / EY / NEI NIH HHS / United States T32EY-07031 / EY / NEI NIH HHS / United States |