Light-dependent redistribution of arrestin in vertebrate rods is an energy-independent process governed by protein-protein interactions.
In rod photoreceptors, arrestin localizes to the outer segment (OS) in the light and to the inner segment (IS) in the dark. Here, we demonstrate that redistribution of arrestin between these compartments can proceed in ATP-depleted photoreceptors. Translocation of transducin from the IS to the OS also does not require energy, but depletion of ATP or GTP inhibits its reverse movement. A sustained presence of activated rhodopsin is required for sequestering arrestin in the OS, and the rate of arrestin relocalization to the OS is determined by the amount and the phosphorylation status of photolyzed rhodopsin. Interaction of arrestin with microtubules is increased in the dark. Mutations that enhance arrestin-microtubule binding attenuate arrestin translocation to the OS. These results indicate that the distribution of arrestin in rods is controlled by its dynamic interactions with rhodopsin in the OS and microtubules in the IS and that its movement occurs by simple diffusion.
Nair
K Saidas
KS
Department of Molecular and Cellular Pharmacology and Neuroscience Program, University of Miami, Miami, Florida 33136, USA.
Hanson
Susan M
SM
Mendez
Ana
A
Gurevich
Eugenia V
EV
Kennedy
Matthew J
MJ
Shestopalov
Valery I
VI
Vishnivetskiy
Sergey A
SA
Chen
Jeannie
J
Hurley
James B
JB
Gurevich
Vsevolod V
VV
Slepak
Vladlen Z
VZ
D000255:Adenosine Triphosphate / Q000172:deficiency; D000818:Animals; D019393:Arrestin / Q000378:metabolism*; D001665:Binding Sites / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D015153:Blotting, Western / Q000379:methods; D003599:Cytoskeleton / Q000378:metabolism; D003623:Dark Adaptation; D003847:Deoxyglucose / Q000494:pharmacology; D004734:Energy Metabolism / Q000502:physiology*; D004789:Enzyme Activation / Q000502:physiology / Q000528:radiation effects; D005136:Eye Proteins; D005455:Fluorescent Antibody Technique; D051606:G-Protein-Coupled Receptor Kinase 1; D005947:Glucose / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000378:metabolism; D019811:Hydroxylamine / Q000494:pharmacology; D066298:In Vitro Techniques; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008870:Microtubules / Q000378:metabolism; D016296:Mutagenesis / Q000502:physiology; D010766:Phosphorylation; D011190:Potassium Cyanide / Q000494:pharmacology; D011485:Protein Binding / Q000502:physiology; D011494:Protein Kinases / Q000172:deficiency; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D012160:Retina / Q000166:cytology*; D017948:Retinal Rod Photoreceptor Cells / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D012243:Rhodopsin / Q000378:metabolism; D017299:Rod Opsins / Q000378:metabolism; D013997:Time Factors; D015293:Transducin / Q000378:metabolism
D019393:Arrestin; D005136:Eye Proteins; D017299:Rod Opsins; D049452:Green Fluorescent Proteins; D019811:Hydroxylamine; D000255:Adenosine Triphosphate; D012243:Rhodopsin; D003847:Deoxyglucose; D011494:Protein Kinases; D051606:G-Protein-Coupled Receptor Kinase 1; C496762:Grk1 protein, mouse; D015293:Transducin; D005947:Glucose; D011190:Potassium Cyanide