TY - JOUR T1 - Background Light Produces a Recoverin-Dependent Modulation of Activated-Rhodopsin Lifetime in Mouse Rods JF - The Journal of Neuroscience JO - J. Neurosci. SP - 1213 LP - 1220 DO - 10.1523/JNEUROSCI.4353-09.2010 VL - 30 IS - 4 AU - Ching-Kang Chen AU - Michael L. Woodruff AU - Frank S. Chen AU - Desheng Chen AU - Gordon L. Fain Y1 - 2010/01/27 UR - http://www.jneurosci.org/content/30/4/1213.abstract N2 - The Ca2+-binding protein recoverin is thought to regulate rhodopsin kinase and to modulate the lifetime of the photoexcited state of rhodopsin (Rh*), the visual pigment of vertebrate rods. Recoverin has been postulated to inhibit the kinase in darkness, when Ca2+ is high, and to be released from the disk membrane in light when Ca2+ is low, accelerating rhodopsin phosphorylation and shortening the lifetime of Rh*. This proposal has remained controversial, in part because the normally rapid turnoff of Rh* has made Rh* modulation difficult to study in an intact rod. To circumvent this problem, we have made mice that underexpress rhodopsin kinase so that Rh* turnoff is rate limiting for the decay of the rod light response. We show that background light speeds the decay of Rh* turnoff, and that this no longer occurs in mice that have had recoverin knocked out. This is the first demonstration in an intact rod that light accelerates Rh* inactivation and that the Ca2+-binding protein recoverin may be required for the light-dependent modulation of Rh* lifetime. ER -