Grant: Master's Award: Canada Graduate Scholarships

Circadian rhythms are biological processes which influence behaviour, physiology and health and which help an organism adapt to its environment. These rhythms are disrupted in many clinical conditions, including depression, drug abuse and Parkinson's disease, and in natural processes such as aging. To better understand the underlying causes of circadian dysregulation in these populations, it is important to first understand the fundamental mechanisms which help to regulate them. Despite the complex array of conditions which can lead to disruption in circadian rhythms, a potential common mechanism that is being investigated is dopamine regulation of the circadian clock genes PER1 and PER2. It has been found that by reducing dopamine in the dorsal striatum, a similar reduction of PER1 and PER2 expression also occurs. Initial information is suggesting a role of a specific type of dopamine receptor, the D2 type receptor, for being responsible for this relationship. For my MSc project, I propose to define more specifically the type of cells involved in clock gene function in the dorsal striatum and how dopamine interacts with signals coming from the cortex in order to regulate these clock genes. I plan to do double immunohistochemistry to identify the cell type expressing PER2 and compare the differences in PER2 expression when dopamine and/or cortical inputs are removed. I hope that my findings will lead to new insight on sleep-wake disturbances in diseases such as Parkinson's.