The human analog of murine cystein rich protein 61 [correction of 16] is a 1alpha,25-dihydroxyvitamin D3 responsive immediate early gene in human fetal osteoblasts: regulation by cytokines, growth factors, and serum.
1Alpha,25-dihydroxyvitamin D3 (1,25-(OH)2D3) is a potent mediator of differentiation and maintenance of specific functions of osteoblasts. To detect novel targets for 1,25-(OH)2D3 action, we applied differential display PCR to human fetal osteoblast-like cells and identified the human analog of murine cystein rich protein 61 (hCYR61) as a 1,25-(OH)2D3-responsive immediate early gene in differentiated fetal osteoblast-like cells. The murine gene CYR61 is important for cell-cell and cell-matrix interactions, and it belongs to an emerging gene family of cysteine-rich proteins. hCYR61 messenger RNA (mRNA) steady-state levels were stimulated 11-fold by 10 nM 1,25-(OH)2D3 by 1 h and declined to control levels by 4 h. This transient stimulation of hCYR61 mRNA was not inhibited by cycloheximide but was prevented by actinomycin D, indicating that the 1,25-(OH)2D3 effect involves transcriptional events and does not require de novo protein synthesis. hCYR61 mRNA stability was not influenced by 1,25(OH)2D3, whereas cycloheximide treatment stabilized hCYR61 mRNA. FCS, as well as growth factors and cytokines such as basic fibroblast growth factor, epidermal growth factor, tumor necrosis factor alpha, and interleukin-1, strongly elevated hCYR61 mRNA steady-state levels within 1 h. hCYR61 mRNA was expressed also in primary human osteoblasts and osteosarcoma cell lines. Using a commercial tissue blot, hCYR61 mRNA was only observed in skeletal muscle. The fast and transient response of hCYR 61 to 1,25-(OH)2D3, serum, growth factors, and cytokines suggests an important role of hCYR61 for osteoblast function and differentiation.
Schütze
N
N
Klinische Forschergruppe, Medizinische Poliklinik, Universität Würzburg, Germany.
Lechner
A
A
Groll
C
C
Siggelkow
H
H
Hüfner
M
M
Köhrle
J
J
Jakob
F
F
D000818:Animals; D001769:Blood; D002117:Calcitriol / Q000494:pharmacology*; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D055515:Cysteine-Rich Protein 61; D004355:Drug Stability; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005333:Fetus / Q000378:metabolism*; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects*; D017781:Genes, Immediate-Early; D006133:Growth Substances / Q000235:genetics*; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics*; D036341:Intercellular Signaling Peptides and Proteins; D007375:Interleukin-1 / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D010006:Osteoblasts / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D017385:Sequence Homology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
C501848:CCN1 protein, human; C491850:CCN1 protein, mouse; D055515:Cysteine-Rich Protein 61; D006133:Growth Substances; D017874:Immediate-Early Proteins; D036341:Intercellular Signaling Peptides and Proteins; D007375:Interleukin-1; D011500:Protein Synthesis Inhibitors; D014409:Tumor Necrosis Factor-alpha; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor; D003513:Cycloheximide; D002117:Calcitriol