Abstract:
Circadian rhythms maintain a 24 hour oscillation pattern in metabolic,
physiological and behavioral processes in all living organisms. Circadian
rhythms are organized as biochemical networks located in hypothalamus
and peripheral tissues. Rhythmicity in the expression of circadian clock
genes plays a vital role in regulating the process of cell division and DNA
damage control. The oncogenic protein, MYC and the tumor suppressor,
p53 are directly influenced by the circadian clock. Jet lag and altered
sleep/wake schedules prominently affect the expression of molecular clock
genes. This study is focused on developing a Petri Net model to analyze
the impacts of long term jet lag on the circadian clock and its probable role
in tumor progression. The results depict that jet lag disrupts the normal
rhythmic behavior and expression of the circadian clock proteins. This dis ruption leads to persistent expression of MYC and suppressed expression of
p53. Thus, it can be inferred that jet lag altered circadian clock negatively
affects the expression of cell cycle regulatory genes causing uncontrolled
proliferation of tumor cells.
