J Korean Acad Periodontol.  2006 Dec;36(4):839-847.

A study on the osteoblast differentiation using osteocalcin gene promoter controlling luciferase expression

• Kim KH
• Park YJ
• Lee YM
• Han JS
• Lee DS
• Lee SJ
• Chung CP
• Seol YJ

Abstract

The aim of this study is to monitor reporter gene expression under osteocalcin gene promoter, using a real-time molecular imaging system, as tool to investigate osteoblast differentiation. The promoter region of mouse osteocalcin gene 2 (mOG2), the best-characterized osteoblast- specific gene, was inserted in promoterless luciferase reporter vector. Expression of reporter gene was confirmed and relationship between the reporter gene expression and osteoblastic differentiation was evaluated. Gene expression according to osteoblstic differentiation on biomaterials, utilizing a real-time molecular imaging system, was monitored. Luciferase was expressed at the only cells transduced with pGL4/mOGP and the level of expression was statistically higher at cells cultured in mineralization medium than cells in growth medium. CCCD camera detected the luciferase expression and was visible differentiation-dependent intensity of luminescence. The cells produced osteocalcin with time-dependent increment in BMP-2 treated cells and there was difference between BMP-2 treated cells and untreated cells at 14days. There was difference at the level of luciferase expression under pGL4/mOGP between BMP-2 treated cells and untreated cells at 3days. CCCD camera detected the luciferase expression at cells transduced with pGL4/mOGP on Ti disc and was visible differentiation-dependent intensity of luminescence This study shows that 1) expression of luciferase is regulated by the mouse OC promoter, 2) the CCCD d etection s ys tem is a r eliable quantitative gene d etection t ool f or t he o s teoblas t differentiation, 3) the dynamics of mouse OC promoter regulation during osteoblast differentiation is achieved in real time and quantitatively on biomaterial. The present system is a very reliable system for monitoring of osteoblast differentiation in real time and may be used for monitoring the effects of growth factors, drug, cytokines and biomaterials on osteoblast differentiation in animal.

Keyword

osteocalcin promoter; OG2; bone differentiation; luciferase; osteoblast

MeSH Terms

Animals
Biocompatible Materials
Cytokines
Gene Expression
Genes, Reporter
Intercellular Signaling Peptides and Proteins
Luciferases*
Luminescence
Mice
Molecular Imaging
Osteoblasts*
Osteocalcin*
Promoter Regions, Genetic
Biocompatible Materials
Cytokines
Intercellular Signaling Peptides and Proteins
Luciferases
Osteocalcin