Different circadian expression of major matrix-related genes in various types of cartilage: modulation by light-dark conditions.
We screened circadian-regulated genes in rat cartilage by using a DNA microarray analysis. In rib growth-plate cartilage, numerous genes showed statistically significant circadian mRNA expression under both 12:12 h light-dark and constant darkness conditions. Type II collagen and aggrecan genes--along with several genes essential for post-translational modifications of collagen and aggrecan, including prolyl 4-hydroxylase 1, lysyl oxidase, lysyl oxidase-like 2 and 3'-phosphoadenosine 5'-phosphosulphate synthase 2--showed the same circadian phase. In addition, the mRNA level of SOX9, a master transcription factor for the synthesis of type II collagen and aggrecan, has a similar phase of circadian rhythms. The circadian expression of the matrix-related genes may be critical in the development and the growth of various cartilages, because similar circadian expression of the matrix-related genes was observed in hip joint cartilage. However, the circadian phase of the major matrix-related genes in the rib permanent cartilage was almost the converse of that in the rib growth-plate cartilage under light-dark conditions. We also found that half of the oscillating genes had conserved clock-regulatory elements, indicating contribution of the elements to the clock outputs. These findings suggest that the synthesis of the cartilage matrix macromolecules is controlled by cell-autonomous clocks depending upon the in vivo location of cartilage.
Department of Dental and Medical Biochemistry, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima 734-8553; Laboratory for Systems Biology, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047; Department of Prosthetic Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588; and Molecular Medicine Laboratories, Institute for Drug Discovery Research, Astellas Pharma Inc., Tsukuba, Ibaraki 305-8585, Japan.
Kiyomasa K
KK
Honda
Takeshi
T
Kawamoto
Hiroki R
HR
Ueda
Ayumu
A
Nakashima
Taichi
T
Ueshima
Rikuhiro G
RG
Yamada
Masahiro
M
Nishimura
Ryo
R
Oda
Shigeo
S
Nakamura
Tomoko
T
Kojima
Mitsuhide
M
Noshiro
Katsumi
K
Fujimoto
Seiichi
S
Hashimoto
Yukio
Y
Kato
D000818:Animals; D002356:Cartilage / Q000378:metabolism*; D057906:Circadian Clocks; D015870:Gene Expression; D006801:Humans; D008297:Male; D064235:Matrilin Proteins / Q000235:genetics / Q000378:metabolism*; D017440:Photoperiod; D051381:Rats; D017207:Rats, Sprague-Dawley
D064235:Matrilin Proteins
cartilage; circadian rhythm; clock; gene expression