Mutagenesis and mapping of a mouse gene, clock essential for circadian behavior

Mutagenesis And Mapping Of A Mouse Gene, Clock Essential For Circadian Behavior Various progresses have been done at the cellular and physiological levels of our understanding of circadian systems even though the molecular mechanisms of circadian clocks have not been fully elucidated (Lowrey, 1). The clock mutants’ isolation and protein synthesis widespread requirements in circadian clock systems show that gene expressions are integral components of the oscillator. Current molecular work with the Neurospora frequency and Drosophila period genes show that circadian cycles of frequency and period transcriptions, in that order, may be lying at the oscillator mechanism heart in the specie (Lowrey, 3). There is no information in existence that shows molecular elements of clock systems found in mammals.
Reports are made on the mouse isolation of mutations that alter two significant circadian rhythms properties: the rhythmicity persistence and the intrinsic period length. When brought together, the given results describe a gene referred to as a clock which is important for normal circadian behavior (Lowrey, 5). Due to the isolation of many clock mutants in different organisms been semi-dominant, the heterozygotes found in the mouse were screened. Due to B6 mice exhibiting robust circadian rhythms, this assay was used in screening circadian mutants. The activity rhythms were observed during light dark cycle exposure. This was to access the entrainment or synchronization behavior. Additionally, in total darkness, it was used in determining the locomotor activity rhythm circulation period (Lowrey, 7).
Laboratory mouse was found to have circadian periods that were less than twenty four hours and the B6 mice were found to have periods averaging between 23. 3 to 23. 8 hours (Lowrey, 8). After testing the G1 which was ENU-treated male offsprings, period length distribution of the activity rhythms of these G1 mice were found to be normal. G1-25 showed circadian periods. They progressively lengthened over the first thirty days.
Questions
1. Why were the activity rhythms observed during light dark cycle exposure?
2. What periods did the B6 mice have?
Work Cited
Lowrey, Philip et. al. “ Mutagenesis and Mapping of a Mouse Gene, Clock, Essential for Circadian Behavior” The journal of Neuroscience. 264 (1994): 1-8.