A lab, field and computer study of the synchronization of circadian rhythms in the subterranean rodent tuco-tuco (Ctenomys aff. knighti)

• Grant number: 11/24120-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2013
• End date: July 23, 2016
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Gisele Akemi Oda
• Grantee: Danilo Eugênio de França Laurindo Flôres
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 13/24740-3 - Effects of photoperiod on the expression of food anticipatory activity in mice: implications to the food- and light-entrainable circadian oscillators, BE.EP.DR

Abstract

Daily rhythms are found in the physiological and behavioral variables of all living beings. Even in the absence of cyclic environmental cues, most of these rhythms persist, but in this case they assume a period that is close to, but different from 24 hours. Therefore, these endogenous rhythms are named circadian rhythms. In a natural environment circadian rhythms present a 24-hour periodicity, because they are synchronized by environmental signals, such as the daily light-dark (LD) cycle. Laboratory experiments that assess the synchronization of circadian rhythm by the daily LD cycle usually use cycles with 12 hours of light versus 12 hours of darkness. In nature, however, some animals may not expose themselves to such long continuous light every day. It is the case, for instance, of the subterranean rodent tuco-tuco (Ctenomys aff. knighti), that remains in its dark subterranean burrows for the greater part of the day. Following the research initiated in my Master's work, by means of a complementary work in field, lab, and computer simulations, the present project intends to investigate the temporal daily pattern of light-exposure in tuco-tucos in the field, and whether this temporal light information synchronizes the tuco-tucos' circadian oscillator. Moreover, as a second objective, we wish to understand the role of feeding schedules on the synchronization of circadian rhythms of the species. We are going to verify whether feeding-fasting daily cycles applied in the laboratory act as synchronizing cues to the activity-rest rhythms of tuco-tucos, herbivorous animals that in theory do not experience temporal restriction of food resources in their natural environment. (AU)

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)

FLORES, DANILO E. F. L.; JANNETTI, MILENE G.; VALENTINUZZI, VERONICA S.; ODA, GISELE A.. Entrainment of circadian rhythms to irregular light/dark cycles: a subterranean perspective. SCIENTIFIC REPORTS, v. 6, OCT 4 2016. (12/15767-2, 13/50482-1, 11/24120-0, 14/20671-0, 14/09324-6)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

FLÔRES, Danilo Eugênio de França Laurindo. Photic and non-photic synchronization of the circadian rhythms in subterranean rodents (Ctenomys aff. knighti) and laboratory model rodents (Mus musculus). 2016. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.