Modeling Natural Photic Entrainment in a Subterranean Rodent (Ctenomys aff. knighti), the Tuco-Tuco

Author(s)

Flores, Danilo E. F. L. ^[1] ; Tomotani, Barbara M. ^[1] ; Tachinardi, Patricia ^[1] ; Oda, Gisele A. ^[1] ; Valentinuzzi, Veronica S. ^[2]

Affiliation

^[1] Univ Sao Paulo, Inst Biociencias, Dept Fisiol, Sao Paulo - Brazil

^[2] Ctr Reg Invest Cient & Transferencia Tecnol CRILA, RA-5301 Anillaco, La Rioja - Argentina

• Document type: Journal article
• Source: PLoS One; v. 8, n. 7 JUL 10 2013.
• Web of Science Citations: 6

Abstract

Subterranean rodents spend most of the day inside underground tunnels, where there is little daily change in environmental variables. Our observations of tuco-tucos (Ctenomys aff. knighti) in a field enclosure indicated that these animals perceive the aboveground light-dark cycle by several bouts of light-exposure at irregular times during the light hours of the day. To assess whether such light-dark pattern acts as an entraining agent of the circadian clock, we first constructed in laboratory the Phase Response Curve for 1 h light-pulses (1000lux). Its shape is qualitatively similar to other curves reported in the literature and to our knowledge it is the first Phase Response Curve of a subterranean rodent. Computer simulations were performed with a non-linear limit-cycle oscillator subjected to a simple model of the light regimen experienced by tuco-tucos. Results showed that synchronization is achieved even by a simple regimen of a single daily light pulse scattered uniformly along the light hours of the day. Natural entrainment studies benefit from integrated laboratory, field and computational approaches. (AU)

• FAPESP's process: 10/50222-1 - Daily core body temperature rhythms in subterranean rodents (Ctenomys knigthi)
• Grantee: Gisele Akemi Oda
• Support Opportunities: Regular Research Grants