Putative roles for phospholipase C-η enzymes in neuronal Ca²⁺ signal modulation.

The most recently identified phospholipase C enzymes (PLC) belong to the PLCη family. Their unique Ca2+ sensitivity and their specific appearance in neurons have attracted great attention since their discovery. However, their physiological role(s) in neurons are still yet to be established. PLCη enzymes are expressed in the neocortex, hippocampus and cerebellum. PLCη2 is also expressed at high levels in pituitary gland, pineal gland and in the retina. Driven by the specific localisation of PLCη enzymes in different brain areas, we discuss here the roles that they may play in neuronal processes including differentiation, memory formation, circadian rhythm regulation, neurotransmitter/hormone release and the pathogenesis of neurodegenerative disorders associated with abberant Ca2+ signalling, such as Alzheimer’s disease.