Through a case study of the controversies surrounding the molecular clock, this paper examines the role of visual representation in the dynamics of scientific controversies. Representations of the molecular clock themselves became objects of controversy and so were not a means for closure. Instead visual representations of the molecular clock became tools for the further articulation of an ongo...

Research Area Basic Biology Keyword Biological clock, circadian rhythm, signal transduction, neuroscience, photobiology Purpose and Background of the Research Most living organisms show a variety of rhythms by virtue of having an intrinsic time-measuring system, called circadian clock, which can be entrained to daily variation of the environmental conditions such as light-dark cycle. In mammals...

Disrupted daily or circadian rhythms of lung function and inflammatory responses are common features of chronic airway diseases. At the molecular level these circadian rhythms depend on the activity of an autoregulatory feedback loop oscillator of clock gene transcription factors, including the BMAL1:CLOCK activator complex and the repressors PERIOD and CRYPTOCHROME. The key nuclear receptors a...

The circadian clock mechanism in the mouse is composed of interlocking transcriptional feedback loops. Two transcription factors, CLOCK and BMAL1, are believed to be essential components of the circadian clock. We have used the Cre-LoxP system to generate whole-animal knockouts of CLOCK and evaluated the resultant circadian phenotypes. Surprisingly, CLOCK-deficient mice continue to express robu...

Albrecht, Urs. Invited Review: Regulation of mammalian circadian clock genes. J Appl Physiol 92: 1348–1355, 2002; 10.1152/japplphysiol. 00759.2001.—The circadian clock is a self-sustaining oscillator that has a period of 24 h and controls many physiological and behavioral systems. This clock can synchronize itself to changing environmental conditions to optimize an organisms performance. The un...

The circadian clock is a self-sustaining oscillator that has a period of approximately 24 h and controls many physiological and behavioral systems. This clock can synchronize itself to changing environmental conditions to optimize an organisms performance. The underlying circadian rhythms are generated by periodic activation of transcription by a set of clock genes. Besides their own regulation...

background: the mammalian ovary is controlled by a number of biological rhythms, which regulate the recruitment and release of mature oocytes. the main objective of this study was to investigate the role of cellular clock proteins during follicle maturation in the mouse estrous ovary. methods: immunohistochemical (ihc) studies were performed on ovaries from 50 estrous staged mice culled at two ...

Recent advances in nanotechnology, electronic technology and biology have enabled the development of bio-inspired nanoscale sensors. The cooperation among the bionanosensors in a network is envisioned to perform complex tasks. Clock synchronization is essential to establish diffusion-based distributed cooperation in the bionanosensor networks. This paper proposes a maximum-likelihood estimator ...