Circadian entrainment to red-light Zeitgebers and action spectrum for entrainment in the jewel wasp Nasonia vitripennis

In this study, we investigated the possibility ofNasonia circadian light entrainment under long-wavelength red LED light –dark cycles and characterized the strength of red light as a potentialZeitgeber. Additionally, we measured the possibility of entrainment under various light intensities (from 5 ·1012 to 4 ·1015 photons ·cm−2·s−1) and a broader range of wavelengths (455 —656 nm) to construct corresponding action spectra for characterizing all circadian photoreceptors involved in photic entrainment. We also conducted electroretinogram (ERG) recordings for each wavelength in the compound eyes. Our findings demonstrate thatNasonia can entrain under red light dark cycles, and the sensory pathway underlying the red-lightZeitgeber response may reside in the ocelli. Combined with findings from previous research, we pose that blue- and green-sensitive rhodopsin photoreceptor cells function as the major circadian photoreceptors in both circadian entrainment by light –dark cycles and circadian phase shifts by light pulses, whereas the red-sensitive photoreceptor cell requires higher light intensity for its role in circadian entrainment by light–dark cycles.
Source: Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology - Category: Physiology Source Type: research