Phenotypic characterization of Knock-in and Knock-out Per3 mice in different photoperiod.

• Grant number: 07/05037-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2008
• End date: December 31, 2010
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal Investigator: Mario Pedrazzoli Neto
• Grantee: Danyella Silva Pereira
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

In 36 years, the history of the basis of circadian rhythmicity was a history of a quickly and successful scientific investigation. The research in the field went from some vaguely indications of a genetic regulation of rhythmic behavior in flies to a wide view of the molecular control of these rhythms in rodents and man. Molecular studies in mammals and in humans have shown that variations in one or more clock genes can modulate trends to morningness or eveningness and also generate circadian rhythms disorders. A variable number of tandem repeat (VNTR) in Per3 gene has been associated with diurnal preference and Delayed Sleep Phase Syndrome (DSPS). The frequency of 4 repeat allele is higher in DSPS patients in England and the opposite allele (5 repeat) is higher in DSPS patients in Brazil. Those differences seem to be related to a strategy of synchronization of Per3 gene in different latitudes, and consequently also in different photoperiods. Animal models are necessary to explore this effect of light during long or short photoperiods. However, as the VNTR of Per3 gene seems to be exclusive of primates, it is not possible to use mice to verify the influence of light in the synchronization related with photoperiod. In order to verify the role of this VNTR in circadian regulation related with photoperiod in Per3 gene, the aim of this project is to develop humanized Knock-in mice with the VNTR and analyze the locomotor activity of animals in different photoperiod to verify the differences between the phase angles of light response.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

PEREIRA, D. S.; VAN DER VEEN, D. R.; GONCALVES, B. S. B.; TUFIK, S.; VON SCHANTZ, M.; ARCHER, S. N.; PEDRAZZOLI, M.. The Effect of Different Photoperiods in Circadian Rhythms of Per3 Knockout Mice. BIOMED RESEARCH INTERNATIONAL, 2014. (98/14303-3, 07/05037-9)

PEREIRA, D. S.; VAN DER VEEN, D. R.; GONCALVES, B. S. B.; TUFIK, S.; VON SCHANTZ, M.; ARCHER, S. N.; PEDRAZZOLI, M.. The Effect of Different Photoperiods in Circadian Rhythms of Per3 Knockout Mice. BIOMED RESEARCH INTERNATIONAL, v. 2014, p. 5-pg., 2014-01-01. (07/05037-9, 98/14303-3)