GSBS Student Publications

Title

The osteocalcin gene: a model for multiple parameters of skeletal-specific transcriptional control

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Cell Biology

Date

8-1-1997

Document Type

Article

Medical Subject Headings

Animals; Chromatin; Chromosome Mapping; *Gene Expression Regulation; Humans; Mice; Mice, Transgenic; Nuclear Matrix; Nucleosomes; Osteocalcin; Promoter Regions (Genetics); Rats; *Transcription, Genetic

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Influences of promoter regulatory elements that are responsive to basal and tissue-restricted transactivation factors, steroid hormones, growth factors and other physiologic mediators has provided the basis for understanding regulatory mechanisms contributing to developmental expression of osteocalcin, tissue specificity and biological activity (reviewed in [1-3]). These regulatory elements and cognate transcription factors support postproliferative transcriptional activation and steroid hormone (e.g. vitamin D) enhancement at the onset of extracellular matrix mineralization during osteoblast differentiation. Three parameters of nuclear structure contribute to osteocalcin gene transcriptional control. The linear representation of promoter elements provides competency for physiological responsiveness within the contexts of developmental as well as phenotype-dependent regulation. Chromatin structure and nucleosome organization reduce distances between independent regulatory elements providing a basis for integrating components of transcriptional control. The nuclear matrix supports gene expression by imposing physical constraints on chromatin related to three dimensional genomic organization. In addition, the nuclear matrix facilitates gene localization as well as the concentration and targeting of transcription factors. Several lines of evidence are presented which are consistent with involvement of multiple levels of nuclear architecture in tissue-specific gene expression during differentiation. Growth factor and steroid hormone responsive modifications in chromatin structure, nucleosome organization and the nuclear matrix are considered which influence transcription of the bone tissue-specific osteocalcin gene during progressive expression of the osteoblast phenotype.

Rights and Permissions

Citation: Mol Biol Rep. 1997 Aug;24(3):185-96.

Related Resources

Link to Article in PubMed

Journal Title

Molecular biology reports

PubMed ID

9291092