Gene expression of periostin in the early stage of fracture healing detected by cDNA microarray analysis.
To comprehensively evaluate gene expression in the early stage of fracture healing, we used a cDNA microarray with 2304 cDNA clones derived from an oligo-capped mouse embryo library. Closed mid-diaphyseal fractures were created in mouse tibiae and expression profiles were analyzed 3 days after fracture. Six genes were up-regulated in comparison to those in unfractured bones and these included three genes previously identified but never shown to be present in fractures, periostin, calumenin, and FHL-1. Cloning of these genes has been completed but their expression pattern and function during fracture healing and bone formation remain to be elucidated. Up-regulation of the six genes was reconfirmed by semi-quantitative RT-PCR analysis. Spatial and temporal expression of one of the newly identified fracture-induced genes, periostin, was analyzed using in situ hybridization, because it displayed the highest up-regulation ratio. A signal for periostin was detected in undifferentiated mesenchymal cells and immature preosteoblastic cells in the periosteal tissues between days 3 and 14 after fracture. Northern analysis showed that periostin gene expression rapidly increased by day 3, reached a peak on day 7, and declined by day 14. These findings suggest that periostin is a specific marker for preosteoblasts and may play an important role in periosteal callus formation during the early stage of fracture healing.
Nakazawa
Tetsuro
T
Department of Orthopaedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan.
Nakajima
Arata
A
Seki
Naohiko
N
Okawa
Akihiko
A
Kato
Masaki
M
Moriya
Hidesige
H
Amizuka
Norio
N
Einhorn
Thomas A
TA
Yamazaki
Masashi
M
D000818:Animals; D015152:Blotting, Northern; D015815:Cell Adhesion Molecules / Q000235:genetics*; D017102:Fracture Healing / Q000502:physiology*; D005786:Gene Expression Regulation; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
D015815:Cell Adhesion Molecules; C082838:Postn protein, mouse