From the Central Nervous System to the Circadian Timing System: New Paradigms on the Road?

E.M. MUÑOZ

Mar del Plata

Conferencia; XXXII Congreso Anual SAN 2017; 2017

Sociedad Argentina de Investigación en Neurociencias-SAN

Now it is known that every cell possesses the molecular machinery to generate its own circadian oscillations. In multicellular organisms, however, a circadian timing system synchronizes each cell to temporal cues according to its need, which modulates overall physiology and behavior. The circadian system is a multisynaptic circuit that transduces photic information into chemical signals, and the pineal gland is one of its key components. How the whole circadian system is developed, and what allows this system to be plastic and adaptive, along with its precision, are questions that are still not fully answered. It has therefore been of special interest for us to study the cellular, molecular and genetic mechanisms behind the ontogeny and plasticity of circadian clocks. We have been using the highly rhythmic pineal gland from conventional and genetically modified rodents, as a biological model. Furthermore, we have been comparing pineal ontogeny to the development of the central nervous system (CNS). Differential mechanisms that involve common players such as transcription factors, have emerged from these comparative studies. The participation of constantly activated microglial cells on pineal ontogeny and homeostasis has also been characterized, as compared with a more complex spectrum of microglia phenotypes in the brain. Recently published data and future avenues will be presented in this talk. It is expected that a better knowledge of normal development of the circadian system will facilitate our understanding of associated pathologies, including developmental disorders and neurodegenerative diseases.