Functional identification of the mouse circadian Clock gene
by transgenic BAC rescue.
Animal studies reveal that the Clock gene
controls the length of a period in a free-running rhythm and it allows an organism to maintain circadian rhythmicity in total darkness.
Interestingly, there is evidence that exposing cultured neural retinal cells of chicken embryos to cycles of light and dark triggers rhythmic expression of clock genes
While the Clock gene
is expressed throughout the brain, it's really only been studied in one particular brain region, which is the one that's involved in circadian rhythms," said Dr.
Since the discovery of the Clock gene
in mice, the list of circadian dock genes identified in mammals has grown in a remarkably short period of time (see table 1).
Musiek studied mice lacking a master clock gene
However, in-depth molecular studies are necessary to elucidate the potential mechanisms by which alcohol directly or indirectly affects clock gene
expression and cellular functions.
METHODS: Glucose tolerance, insulin resistance, and expression of peroxisome proliferator-activated receptor-[alpha] (PPAR-[alpha]) and genes affecting glucose metabolism or fatty acid oxidation and clock gene
rhythms were investigated in wild-type (WT) and AhR-deficient [knockout (KO)] mice.
The researchers exposed normal flies and flies lacking the clock gene
period to one day of high oxygen, which can set off harmful chemical reactions that damage DNA and proteins.
For instance, Stevens and colleagues at Yale including Yong Zhu found that healthy control women showed lower expression of the CLOCK gene
than women with breast cancer.
Estee Lauder scientists are among the first in skincare to understand the role of clock gene
activation and synchronization to enhance skin's natural repair activity.
We were amazed that our data revealed that clock gene
rhythms varied in synchrony across six regions of normal human brain and that these rhythms were significantly disrupted in depressed patients.
The study showed that when administered in animal models the synthetic small molecules altered circadian rhythm and the pattern of core clock gene
expression in the brain's hypothalamus, the site of the master cellular clock that synchronizes daily rhythms in mammals; circadian rhythms are the physiological processes that respond to a 24-hour cycle of light and dark and are present in most living things.
Mice with a mutated Clock gene
are obese and have features of metabolic syndrome, but they show relatively normal activity levels under normal light/dark cycles and show abnormal behavior only in complete darkness.
Georgios Paschos PhD, a research associate in the lab of Garret FitzGerald, MD, FRS director of the Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, found that deletion of the clock gene
Arntl, also known as Bmal1, in fat cells, causes mice to become obese, with a shift in the timing of when this nocturnal species normally eats.