Open AccessStopping the circadian pacemaker with inhibitors of protein synthesis.
Author(s) -
Sat Bir S. Khalsa,
David Whitmore,
Gene D. Block
Publication year - 1992
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.89.22.10862
Subject(s) - anisomycin , circadian rhythm , cycloheximide , protein biosynthesis , ultradian rhythm , rhythm , period (music) , medicine , circadian clock , biology , protein synthesis inhibitor , infradian rhythm , endocrinology , pharmacology , biochemistry , physics , acoustics
The requirement for protein synthesis in the mechanism of a circadian pacemaker was investigated by using inhibitors of protein synthesis. Continuous treatment of the ocular circadian pacemaker of the mollusc Bulla gouldiana with anisomycin or cycloheximide substantially lengthened (up to 39 and 52 hr, respectively) the free-running period of the rhythm. To determine whether high concentrations of inhibitor could stop the pacemaker, long pulse treatments of various durations (up to 44 hr) were applied and the subsequent phase of the rhythm was assayed. The observed phases of the rhythm after the treatments were a function of the time of the end of the treatment pulse, but only for treatments which spanned subjective dawn. The results provide evidence that protein synthesis is required in a phase-dependent manner for motion of the circadian pacemaker to continue.