TY - JOUR
T1 - Involvement of proteins in light resetting ocular circadian oscillators of Aplysia
AU - Raju, U.
AU - Yeung, S. J.
AU - Eskin, A.
PY - 1990
Y1 - 1990
N2 - The effect of inhibitors of protein synthesis on the phase shifting action of light was investigated. Anisomycin and cycloheximide appeared to block advance phase shifts produced by light. This results suggested that light might phase shift by changing the synthesis of some proteins. Examining proteins separated by two-dimensional gel electrophoresis, we found that incorporation of amino acids into 11 proteins was changed during a 6-h light pulse. Nine of these 11 proteins were affected by light in a phase-dependent manner. Elevated extracellular potassium and 8-bromo-guanosine 3',5'-cyclic monophosphate (cGMP), two treatments that mimic effects of light on the rhythm, also changed amino acid incorporation into a number of proteins. All of the five proteins affected by 8 bromo-cGMP were also affected in the same manner by ligth. Three proteins were affected similarly by elevated potassium, light, and 8-bromo-cGMP. Exposure of eyes to label at different times after light treatment showed that the effects of light on some proteins were long lasting. In addition, some proteins were not affected during light but were affected only several hours after light. Some of the eye proteins affected by light were also altered by serotonin (5-HT), another phase-shifting agent. The proteins affected by light, elevated potassium, 8-bromo-cGMP, and 5-HT are candidates for components of circadian system either as an element of the entrainment pathway or the oscillator mechanism.
AB - The effect of inhibitors of protein synthesis on the phase shifting action of light was investigated. Anisomycin and cycloheximide appeared to block advance phase shifts produced by light. This results suggested that light might phase shift by changing the synthesis of some proteins. Examining proteins separated by two-dimensional gel electrophoresis, we found that incorporation of amino acids into 11 proteins was changed during a 6-h light pulse. Nine of these 11 proteins were affected by light in a phase-dependent manner. Elevated extracellular potassium and 8-bromo-guanosine 3',5'-cyclic monophosphate (cGMP), two treatments that mimic effects of light on the rhythm, also changed amino acid incorporation into a number of proteins. All of the five proteins affected by 8 bromo-cGMP were also affected in the same manner by ligth. Three proteins were affected similarly by elevated potassium, light, and 8-bromo-cGMP. Exposure of eyes to label at different times after light treatment showed that the effects of light on some proteins were long lasting. In addition, some proteins were not affected during light but were affected only several hours after light. Some of the eye proteins affected by light were also altered by serotonin (5-HT), another phase-shifting agent. The proteins affected by light, elevated potassium, 8-bromo-cGMP, and 5-HT are candidates for components of circadian system either as an element of the entrainment pathway or the oscillator mechanism.
KW - Biological clocks
KW - Cycloheximide
KW - Phase shift
KW - Protein synthesis
KW - Two-dimensional gel electrophoresis
UR - http://www.scopus.com/inward/record.url?scp=0025056968&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0025056968&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.1990.258.1.r256
DO - 10.1152/ajpregu.1990.258.1.r256
M3 - Article
C2 - 2154135
AN - SCOPUS:0025056968
SN - 0002-9513
VL - 258
SP - R256-R262
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 1 27-1
ER -