Influence of photoperiodic history on clock genes and the circadian pacemaker in the rat retina.
The influence of seasonal lighting conditions on expression of clock genes and the circadian pacemaker was investigated in the rat retina. For this purpose, the 24-h profiles of nine clock genes (bmal1, clock, per1, per2, per3, dec1, dec2, cry1 and cry 2) and the arylalkylamine N-acetyltransferase gene as an indicator of the circadian pacemaker output were compared between light-dark periods of 8 : 16 and 16 : 8 h. The photoperiod influenced the daily patterns of the amount of transcript for per1, per3, dec2 and arylalkylamine N-acetyltransferase. This indicates that photoperiodic information modulates clock gene expression in addition to the circadian pacemaker of the retina. Under constant darkness, photoperiod-dependent changes in the daily profile of the level of transcript persisted for the arylalkylamine N-acetyltransferase gene but not for any of the clock genes. Hence, quantitative expression of each clock gene is influenced by the photoperiod only under the acute light-dark cycle, whereas the pacemaker is capable of storing photoperiodic information from past cycles.
Rohleder
Nils
N
Department of Anatomy and Cell Biology, Johannes Gutenbergy University, 55099 Mainz, Germany.
Langer
Christina
C
Maus
Christian
C
Spiwoks-Becker
Isabella
I
Emser
Angela
A
Engel
Lydia
L
Spessert
Rainer
R
D000704:Analysis of Variance; D000818:Animals; D002940:Circadian Rhythm / Q000235:genetics*; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000502:physiology / Q000528:radiation effects*; D005786:Gene Expression Regulation / Q000502:physiology / Q000528:radiation effects*; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D017440:Photoperiod; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors
D005136:Eye Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger