You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
The Basic-Helix-Loop-Helix-PAS Orphan MOP3 Forms Transcriptionally Active Complexes with Circadian and Hypoxia Factors
John B. Hogenesch, Yi-Zhong Gu, Sanjay Jain and Christopher A. Bradfield
Proceedings of the National Academy of Sciences of the United States of America
Vol. 95, No. 10 (May 12, 1998), pp. 5474-5479
Published by: National Academy of Sciences
Stable URL: http://www.jstor.org/stable/45109
Page Count: 6
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
We report that MOP3 is a general dimerization partner for a subset of the basic-helix-loop-helix (bHLH)-PER-ARNT-SIM (PAS) superfamily of transcriptional regulators. We demonstrated that MOP3 interacts with MOP4, CLOCK, hypoxia-inducible factor 1α (HIF1α ), and HIF2α , A DNA selection protocol revealed that the MOP3-MOP4 heterodimer bound a CACGTGA-containing DNA element. Transient transfection experiments demonstrated that the MOP3-MOP4 and MOP3-CLOCK complexes bound this element in COS-1 cells and drove transcription from a linked luciferase reporter gene. We also deduced the high-affinity DNA binding sites for MOP3-HIF1α complex (TACGTGA) and used transient transfection experiments to demonstrate that the MOP3-HIF1α and MOP3-HIF2α heterodimers bound this element, drove transcription, and responded to cellular hypoxia. Finally, we found that MOP3 mRNA expression overlaps in a number of tissues with each of its four potential partner molecules in vivo.
Proceedings of the National Academy of Sciences of the United States of America © 1998 National Academy of Sciences