We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Combined Pharmacological and Genetic Manipulations Unlock Unprecedented Temporal Elasticity and Reveal Phase-Specific Modulation of the Molecular Circadian Clock of the Mouse Suprachiasmatic Nucleus.
- Authors
Patton, Andrew P.; Chesham, Johanna E.; Hastings, Michael H.
- Abstract
The suprachiasmatic nucleus (SCN) is the master circadian oscillator encoding time-of-day information. SCN timekeeping is sustained by a cell-autonomous transcriptional-translational feedback loop, whereby expression of the Period and Cryptochrome genes is negatively regulated by their protein products. This loop in turn drives circadian oscillations in gene expression that direct SCN electrical activity and thence behavior. The robustness of SCN timekeeping is further enhanced by interneuronal, circuit-level coupling. The aim of this study was to combine pharmacological and genetic manipulations to push the SCN clockwork toward its limits and, by doing so, probe cell-autonomous and emergent, circuit-level properties. Circadian oscillation of mouse SCN organotypic slice cultures was monitored as PER2::LUC bioluminescence. SCN of three genetic backgrounds--wild-type, short-period CKlεTau/Tau mutant, and long-period Fbxl3Afh/Afh mutant--all responded reversibly to pharmacological manipulation with period-altering compounds: picrotoxin, PF-670462 (4-(l-Cyclohexyl-4-(4-fluorophenyl)-lH-imidazol-5-yl]-2-pyrimidinamine dihydrochloride), and KNK437 (N-Formyl-3,4-methylenedioxy-benzylidine-gamma-butyrolactam). This revealed a remarkably wide operating range of sustained periods extending across 25 h, from ≤ 17 h to > 4 2 h. Moreover, this range was maintained at network and single-cell levels. Development of a new technique for formal analysis of circadian waveform, first derivative analysis (FDA), revealed internal phase patterning to the circadian oscillation at these extreme periods and differential phase sensitivity of the SCN to genetic and pharmacological manipulations. For example, FDA of the CK1εTau/Tau mutant SCN treated with the CK1ε-specific inhibitor PF-4800567 (3-[(3-Chlorophenoxy)methyl]-l-(tetrahydro-2H-pyran-4-yl)-lH-pyrazolo[3,4-d]pyrimidin-4-amine hydrochloride) revealed that period acceleration in the mutant is due to inappropriately phased activity of the CKlε isoform. In conclusion, extreme period manipulation reveals unprecedented elasticity and temporal structure of the SCN circadian oscillation.
- Subjects
SUPRACHIASMATIC nucleus; CIRCADIAN rhythms; CRYPTOCHROMES; PYRIMIDINES; IMIDAZOLES
- Publication
Journal of Neuroscience, 2016, Vol 36, Issue 36, p9326
- ISSN
0270-6474
- Publication type
Article
- DOI
10.1523/JNEUROSCI.0958-16.2016