Abstract:
:The daily biological clock regulates the timing of sleep and physiological processes that are of fundamental importance to human health, performance, and well-being. Environmental parameters of relevance to biological clocks include (1) daily fluctuations in light intensity and temperature, and (2) seasonal changes in photoperiod (day length) and temperature; these parameters vary dramatically as a function of latitude and locale. In wide-ranging species other than humans, natural selection has genetically optimized adaptiveness along latitudinal clines. Is there evidence for selection of clock gene alleles along latitudinal/photoperiod clines in humans? A number of polymorphisms in the human clock genes Per2, Per3, Clock, and AANAT have been reported as alleles that could be subject to selection. In addition, this investigation discovered several novel polymorphisms in the human Arntl and Arntl2 genes that may have functional impact upon the expression of these clock transcriptional factors. The frequency distribution of these clock gene polymorphisms is reported for diverse populations of African Americans, European Americans, Ghanaians, Han Chinese, and Papua New Guineans (including 5 subpopulations within Papua New Guinea). There are significant differences in the frequency distribution of clock gene alleles among these populations. Population genetic analyses indicate that these differences are likely to arise from genetic drift rather than from natural selection.
journal_name
J Biol Rhythmsjournal_title
Journal of biological rhythmsauthors
Ciarleglio CM,Ryckman KK,Servick SV,Hida A,Robbins S,Wells N,Hicks J,Larson SA,Wiedermann JP,Carver K,Hamilton N,Kidd KK,Kidd JR,Smith JR,Friedlaender J,McMahon DG,Williams SM,Summar ML,Johnson CHdoi
10.1177/0748730408320284subject
Has Abstractpub_date
2008-08-01 00:00:00pages
330-40issue
4eissn
0748-7304issn
1552-4531pii
23/4/330journal_volume
23pub_type
杂志文章abstract::Since the advent of techniques to investigate gene expression on a large scale, numerous circadian rhythms in mRNA amount have been reported. These rhythms generally differ in amplitude and phase. The authors investigated how far a parameter not regulated by the circadian clock can influence the phase of a rhythm in R...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730408325753
更新日期:2008-12-01 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::Male rose-ringed parakeets (Psittacula krameri) were transferred to a long photoperiod (LP; LD 16:8) or a short photoperiod (SP; LD 8:16) for 45 or 90 days on four dates corresponding to the beginnings of different reproductive phases in an annual testicular cycle, and testicular responsiveness was evaluated by compar...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049200700102
更新日期:1992-04-01 00:00:00
abstract::The mammalian circadian pacemaker is located in the suprachiasmatic nucleus (SCN). Various inputs modulate pacemaker phase, including the serotonergic (5HTergic) input from the midbrain raphe. 5HT phase-advances the SCN pacemaker when applied during mid subjective day. In vitro studies indicate that 5HT advances the m...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873002129002429
更新日期:2002-04-01 00:00:00
abstract::Systematic treatment of hamsters with triazolam (TRZ) or novel wheel (NW) access will yield PRCs similar to those for neuropeptide Y. Both TRZ and NW access require an intact intergeniculate leaflet (IGL) to modulate circadian rhythm phase. It is commonly suggested that both stimulus types influence rhythm phase respo...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873098129000327
更新日期:1998-12-01 00:00:00
abstract::The retinohypothalamic tract (RHT), a monosynaptic retinal projection to the SCN, is the major path by which light entrains the circadian system to the external photoperiod. The circadian system of rodents effectively integrates or counts photons, and the magnitude of the rhythm phase response is proportional to the t...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730405280458
更新日期:2005-12-01 00:00:00
abstract::Mice homozygous for a dominant-negative allele of the Clock gene (Clock (Δ19/Δ19)) have slightly but significantly decreased male fertility. The molecular mechanism for this reduction in fertility is unknown. In the present study, we used a small hairpin RNA (shRNA) strategy to specifically knock down the Clock gene e...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730413486873
更新日期:2013-06-01 00:00:00
abstract::How the cellular elements of the SCN are synchronized to each other is not well understood. We explore circadian oscillations manifest at the level of the cell, the tissue, and the whole animal to better understand intra-SCN synchrony and master clock function of the nucleus. At each level of analysis, responses to va...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730409344800
更新日期:2009-10-01 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::Over 90% of neurons within the suprachiasmatic nucleus (SCN) express γ-aminobutyric acid (GABA). Although GABA is primarily an inhibitory neurotransmitter, in vitro studies suggest that the activation of GABAA receptors (GABAAR) elicits excitation in the adult SCN. The ratio of excitatory to inhibitory responses to GA...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730418782820
更新日期:2018-08-01 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::Life in the Arctic presents organisms with multiple challenges, including extreme photic conditions, cold temperatures, and annual loss and daily movement of sea ice. Polar bears (Ursus maritimus) evolved under these unique conditions, where they rely on ice to hunt their main prey, seals. However, very little is know...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730419900877
更新日期:2020-04-01 00:00:00
abstract::Reduced sensitivity to short-wavelength (blue) light with age has been shown for light-induced melatonin suppression. The current research aimed to determine if a similar age-related reduction occurs in subjective alertness, mood, and circadian phase-advancing responses. Young (n = 11, 23.0 +/- 2.9 years) and older (n...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730408328973
更新日期:2009-02-01 00:00:00
abstract::The hematologic system performs a number of essential functions, including oxygen transport, the execution of the immune response against tumor cells and invading pathogens, and hemostasis (blood clotting). These roles are performed by erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (p...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730415592729
更新日期:2015-10-01 00:00:00
abstract::The large repertoire of circadian rhythms in diverse organisms depends on oscillating central clock genes, input pathways for entrainment, and output pathways for controlling rhythmic behaviors. Stress-activated p38 MAP Kinases (p38K), although sparsely investigated in this context, show circadian rhythmicity in mamma...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730414555183
更新日期:2014-12-01 00:00:00
abstract::The tau mutation in Syrian hamsters (Mesocricetus auratus) is phenotypically expressed in a period of the circadian rhythm of about 20 h in homozygotes (SS) and about 22 h in heterozygotes (S+). The authors investigate whether this well-defined model for variation in circadian period exhibits associated changes in ene...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049701200503
更新日期:1997-10-01 00:00:00
abstract::The classical power spectrum, computed in the frequency domain, outranks traditionally used periodograms derived in the time domain (such as the chi2 periodogram) regarding the search for biological rhythms. Unfortunately, classical power spectral analysis is not possible with unequally spaced data (e.g., time series ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873099129000984
更新日期:1999-12-01 00:00:00
abstract::Arctic and subarctic environments are exposed to extreme light: dark (LD) regimes, including periods of constant light (LL) and constant dark (DD) and large daily changes in day length, but very little is known about circadian rhythms of mammals at high latitudes. The authors investigated the circadian rhythms of a su...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730404264200
更新日期:2004-06-01 00:00:00
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. Thi...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/0748730404268786
更新日期:2004-10-01 00:00:00
abstract::An outstanding unresolved issue in chronobiology is how the level of locomotor activity influences length of the free-running, endogenous circadian period (tau). To address this issue, the authors studied a novel model, 4 replicate lines of laboratory house mice (Mus domesticus) that had been selectively bred for high...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730403256998
更新日期:2003-12-01 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::Although pineal "synaptic" ribbons (SR) are frequently examined by means of quantitative electron microscopy, their functional significance remains unclear. The same is true for related structures--"synaptic" spherules (SPH). In the course of such studies, it has been noted that SR counts may differ from laboratory to...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873048800300103
更新日期:1988-04-01 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::DEC1 and DEC2-basic helix-loop-helix transcription factors-exhibit a circadian expression in the suprachiasmatic nucleus and other peripheral tissues and seem to play roles in regulating the mammalian circadian rhythm by suppressing the CLOCK/BMAL1-activated promoters of Per1, Dec1, and Dec2. The authors present data ...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730405280195
更新日期:2005-10-01 00:00:00
abstract::The aim of this study was to replicate and extend previous work in which the authors observed lower, shorter, and advanced nocturnal melatonin secretion patterns in premenstrually depressed patients compared to those in healthy control women. The authors also sought to test the hypothesis that the therapeutic effect o...
journal_title:Journal of biological rhythms
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1177/074873049701200107
更新日期:1997-02-01 00:00:00
abstract::The measurement of circulating levels of brain-derived neurotrophic factor (BDNF) has been proposed to be a marker of disease and an indicator of recovery. Thus, knowing the temporal pattern and influence of potential circadian rhythms is important. Although several studies have measured BDNF at different times of day...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730417693124
更新日期:2017-02-01 00:00:00
abstract::We examine theoretical models for circadian oscillations based on transcriptional regulation in Drosophila and Neurospora. For Drosophila, the molecular model is based on the negative feedback exerted on the expression of the per and tim genes by the complex formed between the PER and TIM proteins. For Neurospora, sim...
journal_title:Journal of biological rhythms
pub_type: 杂志文章,评审
doi:10.1177/074873099129000948
更新日期:1999-12-01 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::Almost exclusively, photoperiodic insects respond to a given photoperiod in one of two ways: a "long-day" response or a "short-day" response. Intermediate responses occur only at a very restricted range of photoperiods (often less than 30 min) and are generally population phenomena rather than intermediate responses o...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/074873049300800104
更新日期:1993-04-01 00:00:00
abstract::Intertidal species have both circadian and circatidal clocks. Although the behavioral evidence for these oscillators is more than 5 decades old, virtually nothing is known about their molecular clockwork. Pigment-dispersing hormones (PDHs) were originally described in crustaceans. Their insect homologs, pigment-disper...
journal_title:Journal of biological rhythms
pub_type: 杂志文章
doi:10.1177/0748730411420242
更新日期:2011-12-01 00:00:00