AJP - Regu AJP: Renal Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Am J Physiol Regul Integr Comp Physiol (April 23, 2008). doi:10.1152/ajpregu.00134.2008
This Article
Right arrow Full Text (PDF)
Right arrow Supplemental Tables
Right arrow All Versions of this Article:
295/1/R208    most recent
00134.2008v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
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
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Rinaldi, C.
Right arrow Articles by Baldwin, K. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rinaldi, C.
Right arrow Articles by Baldwin, K. M.
Submitted on February 22, 2008
Accepted on April 17, 2008

Intergenic Bidirectional Promoter and Cooperative Regulation of the IIx and IIb MHC Genes in Fast Skeletal Muscle

Chiara Rinaldi1, Fadia Haddad1, Paul W. Bodell2, Anqi X. Qin1, Weihua Jiang1, and Kenneth M. Baldwin3*

1 Physiology & Biophysics, University of California Irvine, Irvine, California, United States
2 Physiology & Biophysics, University of California Irvine, Irvine, California, United States; United States
3 Physiology and Biophysics, University of California Irvine, Irvine, California, United States

* To whom correspondence should be addressed. E-mail: kmbaldwi{at}uci.edu.

This study investigated the dynamic regulation of IIx-IIb MHC genes in the fast white medial gastrocnemius (WMG) muscle in response to intermittent resistance training exercise (RE), a model associated with a rapid shift from IIb to IIx expression (11). We investigated the effect of four days of RE on the transcriptional activity across the skeletal MHC gene locus in the WMG in female Sprague Dawley rats. Our results show that RE resulted in significant shifts from IIb to IIx observed at both the pre-mRNA and mRNA levels. An antisense RNA (xII NAT) was detected in the intergenic region between IIx and IIb, extending across the entire IIx gene and into its promoter. The expression of the xII NAT was positively correlated with IIb pre-mRNA (R=+0.8), and negatively correlated with IIx pre-mRNA (R=-0.8). Transcription mapping of the IIx-IIb intergenic region revealed the generation of sense IIb and xII NATs from a single promoter region. This bidirectional promoter is highly conserved among species and contains several regulatory elements that may be implicated in its regulation. These results suggest that the IIx and the IIb genes are physically and functionally linked via the bidirectional promoter. In order for the IIx MHC gene to be regulated, a feedback mechanism from the intergenic xII NAT is needed. In conclusion, the intergenic bidirectional promoter generating antisense RNA appears to be essential for the coordinated regulation of the skeletal muscle MHC genes during dynamic phenotype shifts.




This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
C. E. Pandorf, W. H. Jiang, A. X. Qin, P. W. Bodell, K. M. Baldwin, and F. Haddad
Calcineurin plays a modulatory role in loading-induced regulation of type I myosin heavy chain gene expression in slow skeletal muscle
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2009; 297(4): R1037 - R1048.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
K. A. Zwetsloot, M. J. Laye, and F. W. Booth
Novel epigenetic regulation of skeletal muscle myosin heavy chain genes. Focus on "Differential epigenetic modifications of histones at the myosin heavy chain genes in fast and slow skeletal muscle fibers and in response to muscle unloading"
Am J Physiol Cell Physiol, July 1, 2009; 297(1): C1 - C3.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
D. L. Allen
Making sense (and antisense) of myosin heavy chain gene expression. Comments on "Intergenic bidirectional promoter and cooperative regulation of the IIx and IIb MHC genes in fast skeletal muscle" by Rinaldi et al.
Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2008; 295(1): R206 - R207.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 2008 by the American Physiological Society.