Clock gene expression in the submandibular glands.
Clock genes, which mediate molecular circadian rhythms, are expressed in a circadian fashion in the suprachiasmatic nucleus and in various peripheral tissues. To establish a molecular basis for circadian regulation in the salivary glands, we examined expression profiles of clock-related genes and salivary gland-characteristic genes. Clock-related genes-including Per1, Per2, Cry1, Bmal1, Dec1, Dec2, Dbp, and Reverbalpha-showed robust circadian expression rhythms in the submandibular glands in 12:12-hour light-dark conditions. In addition, a robust circadian rhythm was observed in amylase 1 mRNA levels, whereas the expression of other salivary-gland-characteristic genes examined was not rhythmic. The Clock mutation resulted in increased or decreased mRNA levels of Per2, Bmal1, Dec1, Dec2, and Dbp, and in Cry1-/- background, Cry2 disruption also increased or decreased mRNA levels of these clock-related genes and the amylase 1 gene. These findings indicate that the Clock- and Cry-dependent molecular clock system is active in the salivary glands.
Furukawa
M
M
Department of Dental and Medical Biochemistry, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima 734-8553, Japan.
Kawamoto
T
T
Noshiro
M
M
Honda
K K
KK
Sakai
M
M
Fujimoto
K
K
Honma
S
S
Honma
K
K
Hamada
T
T
Kato
Y
Y
D056930:ARNTL Transcription Factors; D000681:Amylases / Q000032:analysis; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000032:analysis; D001683:Biological Clocks / Q000235:genetics; D056926:CLOCK Proteins; D018797:Cell Cycle Proteins; D002940:Circadian Rhythm / Q000235:genetics*; D056931:Cryptochromes; D004268:DNA-Binding Proteins / Q000032:analysis; D005420:Flavoproteins / Q000032:analysis; D018257:Helix-Loop-Helix Motifs / Q000235:genetics; D018398:Homeodomain Proteins / Q000032:analysis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D009687:Nuclear Proteins / Q000032:analysis; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1; D056950:Period Circadian Proteins; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis; D013363:Submandibular Gland / Q000201:enzymology / Q000378:metabolism*; D015534:Trans-Activators / Q000032:analysis*; D014157:Transcription Factors / Q000032:analysis
D056930:ARNTL Transcription Factors; D000681:Amylases; D051792:Basic Helix-Loop-Helix Proteins; D056926:CLOCK Proteins; D018797:Cell Cycle Proteins; D056931:Cryptochromes; D004268:DNA-Binding Proteins; D005420:Flavoproteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D056953:Nuclear Receptor Subfamily 1, Group D, Member 1; D056950:Period Circadian Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D015534:Trans-Activators; D014157:Transcription Factors; C538961:Bmal1 protein, mouse; C470968:Bhlhb3 protein, mouse; C491539:Bhlhe40 protein, mouse; C538964:Cry1 protein, mouse; C538967:Cry2 protein, mouse; C498260:Dbp protein, mouse; C498262:Nr1d1 protein, mouse; C513312:Per2 protein, mouse; C538944:Clock protein, mouse