help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sooy, K.
Right arrow Articles by Demay, M. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sooy, K.
Right arrow Articles by Demay, M. B.
Endocrinology Vol. 143, No. 9 3370-3375
Copyright © 2002 by The Endocrine Society

ARTICLE

Transcriptional Repression of the Rat Osteocalcin Gene by {delta}EF1

Karen Sooy and Marie B. Demay

Endocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114

Address all correspondence and requests for reprints to: Marie B. Demay, Wellman 501, Massachusetts General Hospital, 50 Blossom Street, Boston, Massachusetts 02114. E-mail: demay{at}helix.mgh.harvard.edu.

Intron I of the rat osteocalcin gene contains silencer elements that suppress osteocalcin-reporter fusion gene transcription. The consensus sequence for the transcription factor {delta}EF1 is homologous to two pyrimidine-rich repeats in intron 1 that contribute to silencing of osteocalcin-reporter fusion genes. To assess if overexpression of {delta}EF1 augments transcriptional repression by these sequences, the intron 1 sequences (wtS) were placed upstream to the native rat osteocalcin promoter fused to a luciferase reporter gene (-306-OCluc). Coexpression of the wtS-(-306-OCluc) fusion gene with {delta}EF1 decreased luciferase activity 30% relative to cotransfection with empty vector. Repression was abolished by point mutations in the putative {delta}EF1 motifs, mS-(-306-OCluc).

To determine whether {delta}EF1 binds to these DNA sequences, gel retardation assays were performed using oligonucleotides containing the putative osteocalcin {delta}EF1 motifs and a classical {delta}EF1 motif, as radiolabeled probes. A comigrating DNA-protein complex generated by these probes was recognized by an antibody directed against {delta}EF1 and competed for by excess unlabeled wild-type oligonucleotides. Oligonucleotides with mutations in the osteocalcin sequences, which abolish suppression, and in the {delta}EF1 consensus site, that abolishes binding to {delta}EF1, were unable to compete for the formation of this complex. Overexpression of {delta}EF1 in ROS 17/2.8 cells led to an 84% decrease in osteocalcin mRNA levels relative to cells transfected with empty vector, confirming that {delta}EF1 suppresses expression of the endogenous osteocalcin gene.




This article has been cited by other articles:


Home page
 CJASNHome page
M. Kato, L. Arce, and R. Natarajan
MicroRNAs and Their Role in Progressive Kidney Diseases
Clin. J. Am. Soc. Nephrol., July 1, 2009; 4(7): 1255 - 1266.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Cell. Biol.Home page
M. Ponticos, T. Partridge, C. M. Black, D. J. Abraham, and G. Bou-Gharios
Regulation of Collagen Type I in Vascular Smooth Muscle Cells by Competition between Nkx2.5 and {delta}EF1/ZEB1
Mol. Cell. Biol., July 15, 2004; 24(14): 6151 - 6161.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 2002 by The Endocrine Society