Expression and distribution of transcripts for sonic hedgehog in the early phase of fracture repair.
Localization and expression of mRNAs for sonic hedgehog (Shh) at a fracture site in the early phase postfracture were investigated by in situ hybridization and reverse transcription and polymerase chain reaction (RT-PCR). A closed fracture was made in the midshaft of the right tibia of 5-week-old ICR mice, and fractured sites were harvested prefracture (day 0) and on days 2 and 12. In situ hybridization revealed that transcripts for Shh were not detected on day 0, but they were detected in proliferating callus-forming cells in the periosteum and the surrounding tissue, and in the medullary cavity prior to apparent new cartilage and bone formation. Gli 1 (a signaling mediator for Shh) and bone morphogenetic protein-4 transcripts were colocalized with those for Shh transcripts on day 2. The RT-PCR showed that Shh mRNA was detected in the PCR product from day 2, but not from days 0 and 12. These findings are the first description about the activation of Shh gene in the early postfracture reaction.
Miyaji
T
T
Department of Orthopaedic Surgery, Osaka University Medical School, 2-2, Yamadaoka, 565-0871, Suita, Japan.
Nakase
T
T
Iwasaki
M
M
Kuriyama
K
K
Tamai
N
N
Higuchi
C
C
Myoui
A
A
Tomita
T
T
Yoshikawa
H
H
D000818:Animals; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000235:genetics; D001861:Bone Regeneration; D002146:Bony Callus / Q000166:cytology; D053823:Hedgehog Proteins; D017403:In Situ Hybridization; D051741:Kruppel-Like Transcription Factors; D051379:Mice; D008813:Mice, Inbred ICR; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013978:Tibial Fractures / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors; D014018:Tissue Distribution; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics; D000071676:Zinc Finger Protein GLI1
C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; C498520:Gli1 protein, mouse; D053823:Hedgehog Proteins; D051741:Kruppel-Like Transcription Factors; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors; D000071676:Zinc Finger Protein GLI1