Molecular and Cellular Neuroscience Commons^™

Circadian Rhythmic Localization Of Tpa And Pai-1 In The Scn 2.2 Cell Culture May Provide Evidence For Determining The Mechanism Of Gating Photic Phase Shifts, Grayson T Hunley

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Mammalian circadian rhythms are controlled by a central pacemaker located in the suprachiasmatic nucleus (SCN) of the brain. The SCN exhibits endogenous rhythms in neuronal activity and entrains to external stimuli, particularly light. Interestingly, phase shifts in response to light only occur at night and the mechanisms gating phase shifting are not well characterized. Our lab demonstrated that the extracellular protease, tissue-type plasminogen activator (tPA) and its inhibitor, plasminogen activator inhibitor (PAI-1), help gate phase shifting. Total tPA and PAI-1 expression are rhythmic in mouse SCN. These proteins mediate different functions depending on their exact subcellular localization. Therefore, knowing where …