Fig. 5: TRESK negatively regulates glutamatergic receptor signalling in the retino-recipient SCN.
From: TRESK is a key regulator of nocturnal suprachiasmatic nucleus dynamics and light adaptive responses
Under normal conditions (left panel), glutamatergic receptor activity induced by tonic activity from the retino-hypothalamic tract or nocturnal release from astrocytes results in membrane depolarisation and calcium influx. Activation of TRESK by calcium/calcineurin opposes the membrane depolarisation and ensures a hyper-polarised, low firing rate and low intracellular calcium state, which enables efficient light-induced phase-shifting signals. In the absence of TRESK (right panel), the negative feedback mechanism is absent leading to depolarised neurons, high basal firing rate and high intracellular calcium state.
