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A suprachiasmatic-independent circadian clock(s) in the habenula is affected by Per gene mutations and housing light conditions in mice
- Source :
- Brain Structure and Function, Brain Structure and Function, Springer Verlag, 2019, 224 (1), pp.19-31. ⟨10.1007/s00429-018-1756-4⟩
- Publication Year :
- 2018
- Publisher :
- Springer Science and Business Media LLC, 2018.
-
Abstract
- For many years, the suprachiasmatic nucleus (SCN) was considered as the unique circadian pacemaker in the mammalian brain. Currently, it is known that other brain areas are able to oscillate in a circadian manner. However, many of them are dependent on, or synchronized by, the SCN. The Habenula (Hb), localized in the epithalamus, is a key nucleus for the regulation of monoamine activity (dopamine, serotonin) and presents circadian features; nonetheless, the clock properties of the Hb are not fully described. Here, we report, first, circadian expression of clock genes in the lateral habenula (LHb) under constant darkness (DD) condition in wild-type mice which is disturbed in double Per1−/−-Per2Brdm1 clock-mutant mice. Second, using Per2::luciferase transgenic mice, we observed a self-sustained oscillatory ability (PER2::LUCIFERASE bioluminescence rhythmicity) in the rostral and caudal part of the Hb of arrhythmic SCN-ablated animals. Finally, in Per2::luciferase mice exposed to different lighting conditions (light-dark, constant darkness or constant light), the period or amplitude of PER2 oscillations, in both the rostral and caudal Hb, were similar. However, under DD condition or from SCN-lesioned mice, these two Hb regions were out of phase, suggesting an uncoupling of two putative Hb oscillators. Altogether, these results suggest that an autonomous clock in the rostral and caudal part of the Hb requires integrity of circadian genes to tick, and light information or SCN innervation to keep synchrony. The relevance of the Hb timing might reside in the regulation of circadian functions linked to motivational (reward) and emotional (mood) processes.
- Subjects :
- endocrine system
Time Factors
Histology
[SDV]Life Sciences [q-bio]
Photoperiod
Period (gene)
Circadian clock
Biology
050105 experimental psychology
Tissue Culture Techniques
03 medical and health sciences
0302 clinical medicine
Reward
Circadian Clocks
Animals
Epithalamus
0501 psychology and cognitive sciences
Circadian rhythm
Luciferases
ComputingMilieux_MISCELLANEOUS
Lighting
Mice, Knockout
Habenula
Motivation
Behavior, Animal
Suprachiasmatic nucleus
General Neuroscience
05 social sciences
Period Circadian Proteins
Housing, Animal
Cell biology
Mice, Inbred C57BL
CLOCK
PER2
Affect
Mutation
Suprachiasmatic Nucleus
Anatomy
Locomotion
030217 neurology & neurosurgery
Subjects
Details
- ISSN :
- 18632661 and 18632653
- Volume :
- 224
- Database :
- OpenAIRE
- Journal :
- Brain Structure and Function
- Accession number :
- edsair.doi.dedup.....04d76954c2236af01963326350c8b9b7