Putative roles for phospholipase Cη enzymes in neuronal Ca²⁺ signal modulation

The most recently identified PLC (phospholipase C) enzymes 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 localization of PLCη enzymes in different brain areas, in the present paper, we discuss the roles that they may play in neural processes, including differentiation, memory formation, circadian rhythm regulation, neurotransmitter/hormone release and the pathogenesis of neurodegenerative disorders associated with aberrant Ca²⁺ signalling, such as Alzheimer's disease.