Circadian clock controlling arylalkylamine N-acetyltransferase-like activity in the cricket (Gryllus bimaculatus) egg.
When cricket (Gryllus bimaculatus) eggs were incubated under a 12-h light/12-h dark (LD) cycle for 6 days after oviposition at 24-26 degrees C and thereafter transferred to constant darkness (DD), arylalkylamine N-acetyltransferase (NAT)-like activity fluctuated in a circadian manner, peaking during the subjective dark period, and the rhythmic activity persisted during the 3rd day of incubation in DD. When the eggs were transferred from LD to a lighting regime in which the light and dark periods were reversed, the rhythm of NAT-like activity continued to oscillate in phase with the light/dark cycle. These data demonstrate that the cricket egg (probably the embryo) contains a circadian clock controlling NAT-like activity, and that the circadian clock entrains to environmental light/dark cycles.
Department of Chemistry, St. Marianna University School of Medicine, Sugao, Miyamae-ku, Kawasaki 216-8511, Japan.
M T
MT
Itoh
Y
Y
Sumi
D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000378:metabolism*; D002940:Circadian Rhythm / Q000502:physiology*; D003624:Darkness; D006135:Gryllidae / Q000201:enzymology / Q000502:physiology*; D010063:Ovum / Q000201:enzymology*; D017440:Photoperiod
D001191:Arylamine N-Acetyltransferase