TY - JOUR
T1 - Diurnal rhythmic expression of the rhythm-related genes, rPeriod1, rPeriod2, and rClock, in the rat brain
AU - Shieh, Kun Ruey
AU - Yang, Shu Chuan
AU - Lu, Xin Yun
AU - Akil, Huda
AU - Watson, Stanley J.
N1 - Funding Information:
We are grateful to Prof. Ted H. Chiu for a helpful and careful review of this manuscript. We also thank Mr. D.P. Chamberlin for editorial assistance. This study was supported in part by the National Science Council in Taiwan, ROC (NSC 91-2320-B-320-004, NSC 92-2320-B-320-021, and NSC 93-2320-B-320-010) and a Tzu Chi University Research Grant (TCMRC9314A) to Kun-Ruey Shieh.
PY - 2005/1
Y1 - 2005/1
N2 - High densities of the mRNA of three rhythm-related genes, rPeriod1 (rPer1), rPer2, and rClock, which share high homology in Drosophila and mammals, are found in the rat hypothalamic suprachiasmatic nucleus (SCN). The SCN, however, is not the only brain region that expresses these genes. To understand the possible physiological roles of these rhythm-related genes, we examined expression of these genes in different brain regions at various time points in male Sprague - Dawley rats. Using semi quantitativein situ hybridization with 35S-riboprobes to evaluate mRNA levels, the diurnal rhythmicity of rPer1, and rPer2 mRNA levels was found in the SCN, arcuate nucleus, and median eminence/pars tuberalis. Expression patterns of mRNA for rPer1 and rPer2, however, were not similar in these brain regions. The rhythmicity in these brain regions was specific, because it was not observed in the cerebellum or hippocampus. Moreover, diurnal changes in rClock mRNA expression were not detected in any of the brain regions examined. These findings suggest that the different expression patterns observed for rPer1, rPer2, and rClock mRNAs may be attributed to their different physiological roles in these brain regions, and support previous work indicating that circadian rhythms in the brain are widespread.
AB - High densities of the mRNA of three rhythm-related genes, rPeriod1 (rPer1), rPer2, and rClock, which share high homology in Drosophila and mammals, are found in the rat hypothalamic suprachiasmatic nucleus (SCN). The SCN, however, is not the only brain region that expresses these genes. To understand the possible physiological roles of these rhythm-related genes, we examined expression of these genes in different brain regions at various time points in male Sprague - Dawley rats. Using semi quantitativein situ hybridization with 35S-riboprobes to evaluate mRNA levels, the diurnal rhythmicity of rPer1, and rPer2 mRNA levels was found in the SCN, arcuate nucleus, and median eminence/pars tuberalis. Expression patterns of mRNA for rPer1 and rPer2, however, were not similar in these brain regions. The rhythmicity in these brain regions was specific, because it was not observed in the cerebellum or hippocampus. Moreover, diurnal changes in rClock mRNA expression were not detected in any of the brain regions examined. These findings suggest that the different expression patterns observed for rPer1, rPer2, and rClock mRNAs may be attributed to their different physiological roles in these brain regions, and support previous work indicating that circadian rhythms in the brain are widespread.
KW - Arcuate nucleus
KW - Cerebellum
KW - Circadian rhythm
KW - Hippocampus
KW - Pars tuberalis/median eminence
KW - Suprachiasmatic nucleus
UR - http://www.scopus.com/inward/record.url?scp=17744365367&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=17744365367&partnerID=8YFLogxK
U2 - 10.1007/s11373-004-8176-6
DO - 10.1007/s11373-004-8176-6
M3 - Article
C2 - 15864751
AN - SCOPUS:17744365367
SN - 1021-7770
VL - 12
SP - 209
EP - 217
JO - Journal of Biomedical Science
JF - Journal of Biomedical Science
IS - 1
ER -
