Tag Archives: topic:dynamical systems

Oscillations in biological clock gene expression

Life Sciences: Mary Harrington (Smith College)
Mathematics: Tanya Leise (Amherst College)

In mice, the source of the internal clock that maintains internal physiological rhythms in the absence of external cues, is a region of the hypothalamus called the suprachiasmatic nucleus (SCN). Neurons in the SCN exhibit oscillations in mRNA and proteins levels of “clock genes” generated through negative feedback loops in the expression of these genes. Recently, oscillations in clock gene expression have been observed in tissues throughout the body, including lung, liver, and muscle, implying that clocks are in fact distributed throughout the body, synchronized by the master pacemaker in the SCN. This project combines experiments, statistical analysis, and mathematical modeling to explore the effects of shifts of the light-dark cycle on the SCN, and several peripheral tissues (thymus, spleen, esophagus, and liver), of mice. Students with appropriate background will design and run experiments, and the data generated by these experiments will be analyzed using mathematical tools such as wavelets. Deeper implications will be explored through modeling the circadian clock as a dynamical system using differential equations.