Fracture healing induces expression of the proto-oncogene c-fos in vivo. Possible involvement of the Fos protein in osteoblastic differentiation.
Here we report marked in vivo expression of the c-fos gene in the external soft callus (ESC) and periosteal hard callus (PHC) at the fracture site of adult rat tibia. Northern-blot analysis showed that the ESC expressed a high level of c-fos mRNA from post-fracture day 10 to day 28, the time when endochondral ossification progressed, and that the ossifying PHC also expressed c-fos mRNA. This c-fos expression was followed by sequential expression of the genes for alkaline phosphatase, osteopontin and osteocalcin, which are osteoblastic markers. Immunohistochemical analysis showed that the c-Fos protein was predominantly located in osteoblasts in the ossifying calluses.
Ohta
S
S
Department of Orthopaedic Surgery, Kyoto University Faculty of Medicine, Japan.
Yamamuro
T
T
Lee
K
K
Okumura
H
H
Kasai
R
R
Hiraki
Y
Y
Ikeda
T
T
Iwasaki
R
R
Kikuchi
H
H
Konishi
J
J
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015152:Blotting, Northern; D002454:Cell Differentiation / Q000235:genetics; D005260:Female; D050723:Fractures, Bone; D015870:Gene Expression; D007150:Immunohistochemistry; D010006:Osteoblasts / Q000166:cytology*; D015675:Osteocalcin / Q000235:genetics / Q000378:metabolism; D053495:Osteopontin; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016760:Proto-Oncogene Proteins c-fos; D011519:Proto-Oncogenes; D051381:Rats; D011919:Rats, Inbred Strains; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism; D014945:Wound Healing / Q000235:genetics
D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D012795:Sialoglycoproteins; C506897:Spp1 protein, rat; D015675:Osteocalcin; D053495:Osteopontin; D000469:Alkaline Phosphatase