Circadian Control of Chloroplast Transcription by a Nuclear-Encoded Timing Signal

Science ◽  
2013 ◽  
Vol 339 (6125) ◽  
pp. 1316-1319 ◽  
Author(s):  
Z. B. Noordally ◽  
K. Ishii ◽  
K. A. Atkins ◽  
S. J. Wetherill ◽  
J. Kusakina ◽  
...  
Keyword(s):  
Chloroplast Transcription ◽  
Circadian Control

scholarly journals Divergent Importance of Chronobiological Considerations in High- and Low-dose Melatonin Therapies

Diseases ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 18
Author(s):  
Rüdiger Hardeland
Keyword(s):  
Phase Response Curve ◽  
Sleep Onset ◽  
Melatonin Receptors ◽  
Duration Of Action ◽  
Circadian Oscillators ◽  
Protective Actions ◽  
Circadian Control ◽  
Dim Light ◽  
Poor Individual ◽  
Specific Phase

Melatonin has been used preclinically and clinically for different purposes. Some applications are related to readjustment of circadian oscillators, others use doses that exceed the saturation of melatonin receptors MT1 and MT2 and are unsuitable for chronobiological purposes. Conditions are outlined for appropriately applying melatonin as a chronobiotic or for protective actions at elevated levels. Circadian readjustments require doses in the lower mg range, according to receptor affinities. However, this needs consideration of the phase response curve, which contains a silent zone, a delay part, a transition point and an advance part. Notably, the dim light melatonin onset (DLMO) is found in the silent zone. In this specific phase, melatonin can induce sleep onset, but does not shift the circadian master clock. Although sleep onset is also under circadian control, sleep and circadian susceptibility are dissociated at this point. Other limits of soporific effects concern dose, duration of action and poor individual responses. The use of high melatonin doses, up to several hundred mg, for purposes of antioxidative and anti-inflammatory protection, especially in sepsis and viral diseases, have to be seen in the context of melatonin’s tissue levels, its formation in mitochondria, and detoxification of free radicals.

scholarly journals Period Protein Is Necessary for Circadian Control of Egg Hatching Behavior in the Silkmoth Antheraea pernyi

Neuron ◽  
1996 ◽  
Vol 17 (5) ◽  
pp. 901-909 ◽  
Author(s):  
Ivo Sauman ◽  
Tony Tsai ◽  
Alfred L Roca ◽  
Steven M Reppert
Keyword(s):  
Egg Hatching ◽  
Antheraea Pernyi ◽  
Circadian Control

scholarly journals Cryptochromes regulate IGF-1 production and signaling through control of JAK2-dependent STAT5B phosphorylation

2017 ◽  
Vol 28 (6) ◽  
pp. 834-842 ◽  
Author(s):  
Amol Chaudhari ◽  
Richa Gupta ◽  
Sonal Patel ◽  
Nikkhil Velingkaar ◽  
Roman Kondratov
Keyword(s):  
Circadian Rhythms ◽  
Circadian Clock ◽  
Skeletal Muscles ◽  
Cancer Metabolism ◽  
Reduced Body ◽  
Circadian Control ◽  
Cell Growth And Proliferation ◽  
Deficient Mice ◽  
Igf Signaling

Insulin-like growth factor (IGF) signaling plays an important role in cell growth and proliferation and is implicated in regulation of cancer, metabolism, and aging. Here we report that IGF-1 level in blood and IGF-1 signaling demonstrates circadian rhythms. Circadian control occurs through cryptochromes (CRYs)—transcriptional repressors and components of the circadian clock. IGF-1 rhythms are disrupted in Cry-deficient mice, and IGF-1 level is reduced by 80% in these mice, which leads to reduced IGF signaling. In agreement, Cry-deficient mice have reduced body (∼30% reduction) and organ size. Down-regulation of IGF-1 upon Cry deficiency correlates with reduced Igf-1 mRNA expression in the liver and skeletal muscles. Igf-1 transcription is regulated through growth hormone–induced, JAK2 kinase–mediated phosphorylation of transcriptional factor STAT5B. The phosphorylation of STAT5B on the JAK2-dependent Y699 site is significantly reduced in the liver and skeletal muscles of Cry-deficient mice. At the same time, phosphorylation of JAK2 kinase was not reduced upon Cry deficiency, which places CRY activity downstream from JAK2. Thus CRYs link the circadian clock and JAK-STAT signaling through control of STAT5B phosphorylation, which provides the mechanism for circadian rhythms in IGF signaling in vivo.

scholarly journals Circadian Control of Fatty Acid Elongation by SIRT1 Protein-mediated Deacetylation of Acetyl-coenzyme A Synthetase 1

2014 ◽  
Vol 289 (9) ◽  
pp. 6091-6097 ◽  
Author(s):  
Saurabh Sahar ◽  
Satoru Masubuchi ◽  
Kristin Eckel-Mahan ◽  
Simone Vollmer ◽  
Luisa Galla ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Coenzyme A ◽  
Fatty Acid Elongation ◽  
Acetyl Coenzyme A ◽  
Acetyl Coenzyme ◽  
Circadian Control
Sign in / Sign up

Export Citation Format

Share Document