Recoverin undergoes light-dependent intracellular translocation in rod photoreceptors

J Biol Chem. 2005 Aug 12;280(32):29250-5. doi: 10.1074/jbc.M501789200. Epub 2005 Jun 16.


Photoreceptor cells have a remarkable capacity to adapt the sensitivity and speed of their responses to ever changing conditions of ambient illumination. Recent studies have revealed that a major contributor to this adaptation is the phenomenon of light-driven translocation of key signaling proteins into and out of the photoreceptor outer segment, the cellular compartment where phototransduction takes place. So far, only two such proteins, transducin and arrestin, have been established to be involved in this mechanism. To investigate the extent of this phenomenon we examined additional photoreceptor proteins that might undergo light-driven translocation, focusing on three Ca(2+)-binding proteins, recoverin and guanylate cyclase activating proteins 1 (GCAP1) and GCAP2. The changes in the subcellular distribution of each protein were assessed quantitatively using a recently developed technique combining serial tangential sectioning of mouse retinas with Western blot analysis of the proteins in the individual sections. Our major finding is that light causes a significant reduction of recoverin in rod outer segments, accompanied by its redistribution toward rod synaptic terminals. In both cases the majority of recoverin was found in rod inner segments, with approximately 12% present in the outer segments in the dark and less than 2% remaining in that compartment in the light. We suggest that recoverin translocation is adaptive because it may reduce the inhibitory constraint that recoverin imposes on rhodopsin kinase, an enzyme responsible for quenching the photo-excited rhodopsin during the photoresponse. To the contrary, no translocation of rhodopsin kinase itself or either GCAP was identified.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Blotting, Western
  • Calcium / metabolism
  • Calcium-Binding Proteins / metabolism
  • Calcium-Binding Proteins / physiology*
  • DNA, Complementary / metabolism
  • Eye Proteins / metabolism
  • Eye Proteins / physiology*
  • Guanylate Cyclase-Activating Proteins
  • Light
  • Lipoproteins / metabolism
  • Lipoproteins / physiology*
  • Mice
  • Mice, Inbred C57BL
  • Protein Kinase Inhibitors / metabolism
  • Protein Transport
  • RNA, Messenger / metabolism
  • Recoverin
  • Retina / metabolism
  • Retina / pathology
  • Retinal Rod Photoreceptor Cells / metabolism*
  • Rhodopsin / metabolism
  • Signal Transduction
  • beta-Cyclodextrins / metabolism


  • Calcium-Binding Proteins
  • DNA, Complementary
  • Eye Proteins
  • Guanylate Cyclase-Activating Proteins
  • Guca1a protein, mouse
  • Guca1b protein, mouse
  • Lipoproteins
  • Protein Kinase Inhibitors
  • RNA, Messenger
  • Rcvrn protein, mouse
  • beta-Cyclodextrins
  • Recoverin
  • Rhodopsin
  • Calcium