Abstract:
:The mammalian SCN contains a biological clock that drives remarkably precise circadian rhythms in vivo and in vitro. Recent advances have revealed molecular and cellular mechanisms required for the generation of these daily rhythms and their synchronization between SCN neurons and to the environmental light cycle. This review of the evidence for a cell-autonomous circadian pacemaker within specialized neurons of the SCN focuses on 6 genes implicated within the pace making mechanism, an additional 4 genes implicated in pathways from the pacemaker, and the intercellular and intracellular mechanisms that synchronize SCN neurons to each other and to solar time.
journal_name
J Biol Rhythmsjournal_title
Journal of biological rhythmsauthors
Hastings MH,Herzog EDdoi
10.1177/0748730404268786subject
Has Abstractpub_date
2004-10-01 00:00:00pages
400-13issue
5eissn
0748-7304issn
1552-4531pii
19/5/400journal_volume
19pub_type
杂志文章,评审abstract::Rats anticipate a fixed daily feeding time by entrainment of a component of their multioscillatory circadian system. The range of stimuli capable of entraining this component is little studied. Previous studies suggest that restricted water access is not an effective entrainment stimulus, as measured by general locomo...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049200700206
更新日期:1992-07-01 00:00:00
abstract::In our attempts to understand the circadian system, we unavoidably rely on abstractions. Instead of describing the behavior of the circadian system in all its complexity, we try to derive basic features from which we form a global concept on how the system works. Such a basic concept is a model of reality. The author ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730405277388
更新日期:2005-08-01 00:00:00
abstract::Most visual system functions, such as opsin gene expression, retinal neural transmission, light perception, and visual sensitivity, display robust day-night rhythms. The rhythms persist in constant lighting conditions, suggesting the involvement of endogenous circadian clocks. While the circadian pacemakers that contr...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730419863917
更新日期:2019-10-01 00:00:00
abstract::Activity patterns are the product of interactions between an internal circadian clock and direct responses to photic and nonphotic features of the environment that are said to "mask" the influence of that clock. Evolutionary transitions between nocturnality and diurnality involve changes in mechanisms underlying both ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730409351672
更新日期:2010-02-01 00:00:00
abstract::Drosophila littoralis is a latitudinally widespread European species of the Drosophila virilis group. The species has ample genetic variation in photoperiodism (adult diapause) and circadian rhythmicity (pupal eclosion rhythm), with adaptive latitudinal clines in both of them. The possible common genetic basis between...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730405283418
更新日期:2006-02-01 00:00:00
abstract::Odors elicit a number of behavioral responses, including attraction and repulsion in Drosophila. In this study, the authors used a T-maze apparatus to show that wild-type Drosophila melanogaster exhibit a robust circadian rhythm in the olfactory attractive and repulsive responses. These responses were lower during the...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730405274451
更新日期:2005-06-01 00:00:00
abstract::In Drosophila melanogaster, disruption of night by even short light exposures results in degradation of the clock protein TIMELESS (TIM), leading to shifts in the fly molecular and behavioral rhythms. Several lines of evidence indicate that light entrainment of the brain clock involves the blue-light photoreceptor cry...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873040101600303
更新日期:2001-06-01 00:00:00
abstract::The role of the intergeniculate leaflet of the thalamus (IGL) in photoperiod responsiveness was examined in a laboratory-selected line of photoperiod nonresponsive (NR) Siberian hamsters. NR hamsters fail to exhibit typical winter-type responses (i.e., gonadal regression and development of winter-type pelage) when exp...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730406287996
更新日期:2006-06-01 00:00:00
abstract::In many animals, the circadian clock plays a role in adapting to the coming season by measuring day length. The mechanism for measuring day length and its neuronal circuits remains elusive, however. Under laboratory conditions, the fruit fly, Drosophila melanogaster, displays 2 activity peaks: one in the morning and o...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730417738612
更新日期:2018-02-01 00:00:00
abstract::The mammalian circadian clock in the suprachiasmatic nucleus (SCN) drives and maintains 24-h physiological rhythms, the phases of which are set by the local environmental light-dark cycle. Gastrin-releasing peptide (GRP) communicates photic phase setting signals in the SCN by increasing neurophysiological activity of ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730410396678
更新日期:2011-04-01 00:00:00
abstract::Circadian rhythms are programmed by the suprachiasmatic nucleus (SCN), which relies on neuropeptide signaling to maintain daily timekeeping. Vasoactive intestinal polypeptide (VIP) is critical for SCN function, but the precise role of VIP neurons in SCN circuits is not fully established. To interrogate their contribut...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730420925573
更新日期:2020-08-01 00:00:00
abstract::The circadian rhythm of eclosion activity and its pacemaker were analyzed in a series of latitudinal races of Drosophila auraria ranging from 34.2 degrees to 42.9 degrees N in Japan. The phase of the rhythm (psi EL) to the daily photoperiod (PP) changes as daylength is increased, and the slope of psi EL (PP) changes w...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:
更新日期:1989-07-01 00:00:00
abstract::Various aspects of mammalian endocrine physiology show a time-of-day variation with a period of 24 h, which represents an adaptation to the daily environmental fluctuations resulting from the rotation of the earth. These 24-h rhythms in hormone abundance and consequently hormone function may rely on rhythmic signals p...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730415580881
更新日期:2015-08-01 00:00:00
abstract::The ventral subparaventricular zone (vSPVZ) receives direct retinal input and influences the daily patterning of activity in rodents, making it a likely candidate for the mediation of acute behavioral responses to light (i.e., masking). We performed chemical lesions aimed at the vSPVZ of diurnal grass rats (Arvicanthi...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730415626251
更新日期:2016-04-01 00:00:00
abstract::A rhythm mutant of Drosophila melanogaster was induced by chemical mutagenesis and isolated by testing for locomotor activity rhythms, which in the new variant had periods of approximately 16 hr. The sex-linked mutation responsible for this ultrashort period causes 20-hr rhythms when heterozygous with a normal X. This...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049400900303
更新日期:1994-01-01 00:00:00
abstract::The purpose of this study was to determine whether decreased day lengths affect reproduction or the immune system in inbred mice. Irrespective of a nocturnal pineal melatonin rise, the signal for day length information, body and testis weights were the same in various strains 8 weeks after transfer from long to short ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873002129002348
更新日期:2002-02-01 00:00:00
abstract::The authors examined spatial working memory in the Morris water maze during the activity and rest periods of Wistar rats. Wheel-running activity was measured continuously as a marker of circadian phase. To minimize possible masking effects on performance, animals were placed in constant dim light the day before testin...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730404265688
更新日期:2004-08-01 00:00:00
abstract::The Drosophila clock relies on transcriptional feedback loops that generate daily oscillations of the clock gene expression at mRNA and protein levels. In the evening, the CLOCK (CLK) and CYCLE (CYC) basic helix-loop-helix (bHLH) PAS-domain transcription factors activate the expression of the period (per) and timeless...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730407313817
更新日期:2008-04-01 00:00:00
abstract::Endogenous circadian rhythms are involved in various photoperiodic responses of birds. Investigations involving the mechanisms of photoperiodic time measurement in birds have been confined mainly to temperate zone species using males exclusively. Due to the paucity of experimental evidence on subtropical birds that ha...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049501000405
更新日期:1995-12-01 00:00:00
abstract::The circadian clock represents an anticipatory mechanism, well preserved in evolution. It has a critical impact on most aspects of the physiology of light-sensitive organisms. These rhythmic processes are governed by environmental cues (fluctuations in light intensity and temperature), an internal circadian timing sys...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730414557634
更新日期:2015-04-01 00:00:00
abstract::Groups of Syrian hamsters were exposed to LD cycles with twilight transitions and photoperiods simulating natural lighting conditions at the summer solstice (SS), equinox, and winter solstice (WS) at 41 degrees N and at the winter solstice at the Arctic Circle (WS 66 degrees N) but with daytime illuminance truncated a...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730404272907
更新日期:2005-04-01 00:00:00
abstract::To determine if a circadian rhythm known to be functionally related to the reproductive axis varies on a circannual basis, we monitored the circadian secretion of melatonin at monthly intervals for 2 years in four ovariectomized, estradiol-implanted ewes held in a constant short-day photoperiod. Prior to the study, ew...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049501000104
更新日期:1995-03-01 00:00:00
abstract::The human circadian timing system has previously been shown to free run with a period slightly longer than 24 h in subjects living in the laboratory under conditions of forced desynchrony. In forced desynchrony, subjects are shielded from bright light and periodic time cues and are required to live on a day length out...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873099129000597
更新日期:1999-06-01 00:00:00
abstract::Perhaps the most observable of the many circadian oscillations that have been described in both vertebrate and invertebrate animals is the daily alterations in periods of rest and activity. Recent studies in the fruit fly Drosophila melanogaster suggest that these periods of inactivity are not simply rest but share ma...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730402239672
更新日期:2003-02-01 00:00:00
abstract::Although overt diurnal rhythms of behavior do not begin until well after birth, molecular studies suggest that the circadian clock may begin much earlier at a cellular level: mouse embryonic fibroblasts, for example, already possess robust clocks. By multiple criteria, we found no circadian clock present in mouse embr...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730410385281
更新日期:2010-12-01 00:00:00
abstract::In mammals, the suprachiasmatic nucleus (SCN) is the central pacemaker organizing circadian rhythms of behavior and physiology. At the cellular level, the mammalian clock consists of autoregulatory feedback loops involving a set of "clock genes," including the Cryptochrome (Cry) genes, Cry1 and Cry2. Experimental evid...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730412461246
更新日期:2012-12-01 00:00:00
abstract::Previous research has demonstrated a clear link between late chronotype and depression. The vulnerability factors underpinning this link, however, are unclear. Here the relationship between two specific emotion regulation strategies, cognitive reappraisal and expressive suppression, and chronotype was investigated usi...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730417709111
更新日期:2017-08-01 00:00:00
abstract::The synchronizing stimulus, its transduction site, and the afferent pathways responsible for feeding entrainment remain unknown. In fish, the role of the diet in the development of feeding anticipatory activity (FAA) is not well understood and fundamental questions on the mechanisms of feeding entrainment, such as the...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873040101600107
更新日期:2001-02-01 00:00:00
abstract::Ground squirrels, Spermophilus tridecemlineatus, were kept in a 12:12 h light-dark cycle. As expected for a diurnal species, their locomotor activity occurred almost entirely in the daytime. Expression of mPer1 and mPer2 in the suprachiasmatic nucleus was studied at six time points by in situ hybridization. For both t...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873001129002141
更新日期:2001-10-01 00:00:00
abstract::Threads of evidence from recent experimentation in retinal morphology, neurochemistry, electrophysiology, and visual perception point toward rhythmic ocular processes that may be integral components of circadian entrainment in mammals. Components of retinal cell biology (rod outer-segment disk shedding, inner-segment ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/074873049100600104
更新日期:1991-04-01 00:00:00