Abstract:
: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.
journal_name
Proc Natl Acad Sci U S Aauthors
Khalsa SB,Whitmore D,Block GDdoi
10.1073/pnas.89.22.10862keywords:
subject
Has Abstractpub_date
1992-11-15 00:00:00pages
10862-6issue
22eissn
0027-8424issn
1091-6490journal_volume
89pub_type
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