Abstract
Animals anticipate the timing of food availability via the food-entrainable oscillator (FEO). The anatomical location and timekeeping mechanism of the FEO are unknown. Several studies showed the circadian gene, Period 2, is critical for FEO timekeeping. However, other studies concluded that canonical circadian genes are not essential for FEO timekeeping. In this study, we re-examined the effects of the Per2Brdm1 mutation on food entrainment using methods that have revealed robust food anticipatory activity in other mutant lines. We examined food anticipatory activity, which is the output of the FEO, in single Period mutant mice. Single Per1, Per2, and Per3 mutant mice had robust food anticipatory activity during restricted feeding. In addition, we found that two different lines of Per2 mutant mice (ldc and Brdm1) anticipated restricted food availability. To determine if FEO timekeeping persisted in the absence of the food cue, we assessed activity during fasting. Food anticipatory (wheel-running) activity in all Period mutant mice was also robust during food deprivation. Together, our studies demonstrate that the Period genes are not necessary for the expression of food anticipatory activity.
Highlights
The food-entrainable oscillator (FEO) is an enigmatic circadian pacemaker that is entrained by temporally restricted food availability[1]
We first determined if C57BL/6 J Period[1], Period[2], and Period[3] mutant mice[14] expressed food anticipatory activity during daytime restricted feeding (ZT6-10) and subsequent fasting
The Period genes are critical for timekeeping in canonical circadian clocks
Summary
The food-entrainable oscillator (FEO) is an enigmatic circadian pacemaker that is entrained by temporally restricted food availability[1]. Mice display anticipatory activity (the output of the FEO) prior to food availability. Recent studies have shown that the molecular timekeeping mechanism of the FEO operates differently compared to canonical circadian oscillators (e.g. SCN, liver, lung). This was first demonstrated in homozygous Clock Δ19 mutant mice that have arrhythmic SCN-controlled nocturnal activity, but normal FEO-controlled food anticipatory activity[6]. We sought to re-examine the roles of the Period genes in food entrainment
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call