Effect of a RNA-Binding Protein (RBP) on the dynamics of the molecular clock.

NIETO, P.S.; REVELLI, J.A.; GARBARINO-PICO, E.; GUIDO, M. E.; TAMARIT, F.A.

Mendoza

Congreso; XLVIII Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB 2012); 2012

Sociedad Argentina de Investigación Bioquímica y Biología Molecular

<!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } -->Most living beings exhibit physiological and behavioural circadian rhythms with an endogenous period of about 24 h, which can be synchronized and anticipate to periodic cues. At molecular level, the circadian timekeeping mechanism is driven by a set of genes, called clock genes which interact in oscillatory transcriptional-translational networks within cells. The majority of mammalian cells have a circadian molecular clock and they are coordinated by a master circadian pacemaker in the mammalian brain called the suprachiasmatic nucleus (SCN).Numerous observations have revealed the importance of post-transcriptional regulation on circadian gene expression (Garbarino-Pico and Green 2007) and recent studies have demonstrated that several clock genes are post-translationally regulated by RBPs (reviewed in Lowrey and Takahashi 2011 and Garbarino-Pico et al., 2011) . In the present work we show numerical results obtained with a mathematical model for the circadian molecular clock, which includes the regulation of Per mRNA translation by a RBP. We found that depending on the values of the RBP-associated parameters, the period and amplitude of the oscillator are affected. The magnitude of those changes depend on whether the repression of transcription is assumed as a cooperative or non-cooperative event.