Role of a new member of IGFBP superfamily, IGFBP-rP10, in proliferation and differentiation of osteoblastic cells.
Bone regeneration is critically regulated by various molecules. To identify the new genes involved in bone regeneration, we performed microarray-based gene expression analysis using a mouse bone regeneration model. We identified a new member of the IGFBP superfamily, designated IGFBP-rP10, whose expression is up-regulated at the early phase of bone regeneration. IGFBP-rP10 consists of an IGFBP homologous domain followed by a Kazal-type protein inhibitor domain and an immunoglobulin G-like domain. A real-time-based RT-PCR analysis demonstrated that various tissues including bone expressed IGFBP-rP10 mRNA in various degrees, and confirmed an up-regulation at the early phase of bone regeneration. In situ hybridization revealed that osteoblastic cells expressed IGFPB-rP10 mRNA during bone regeneration. Bone morphogenetic protein-2 increased the expression level of IGFBP-rP10 mRNA in various cells including C3H10T1/2, MC3T3-E1, C2C12, and primary murine osteoblastic cells. The addition of recombinant mouse IGFBP-rP10 promoted the proliferation of these cells but failed to stimulate alkaline phosphatase activity. These results suggest that IGFBP-rP10 is involved in the proliferation of osteoblasts during bone formation and bone regeneration.
Shibata
Yasuaki
Y
Division of Oral Pathology and Bone Metabolism, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan.
Tsukazaki
Tomoo
T
Hirata
Kazunari
K
Xin
Cheng
C
Yamaguchi
Akira
A
D000595:Amino Acid Sequence; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology*; D002454:Cell Differentiation; D049109:Cell Proliferation; D005269:Femur / Q000293:injuries / Q000378:metabolism / Q000473:pathology; D018969:Insulin-Like Growth Factor Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010006:Osteoblasts / Q000378:metabolism* / Q000473:pathology*; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014945:Wound Healing / Q000502:physiology*
D018969:Insulin-Like Growth Factor Binding Proteins; C495062:Kazald1 protein, mouse; D011994:Recombinant Proteins