help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
This version published online on December 18, 2003
Endocrinology, doi:10.1210/en.2003-1051
A more recent version of this article appeared on April 1, 2004
This Article
Right arrow Author Manuscript (PDF)
Right arrow All Versions of this Article:
145/4/1617    most recent
Author Manuscript (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
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
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 Kalma, Y.
Right arrow Articles by Dekel, N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kalma, Y.
Right arrow Articles by Dekel, N.

Submitted on August 13, 2003
Accepted on December 4, 2003

LH-Induced Connexin 43 Down Regulation: Inhibition of Translation

Yael Kalma1, Irit Granot1, Dalia Galiani1, Amihai Barash1, and Nava Dekel1*

1 Department of Biological Regulation, The Weizmann Institute of Science, Rehovot, Israel,; In Vitro Fertilization Unit, Department of Obstetric and Gynecology, Kaplan Medical Center, Rehovot, Israel

* To whom correspondence should be addressed. E-mail: nava.dekel{at}weizmann.ac.il.

The coordinated function of the different compartments of the follicle, the oocyte and the somatic cumulus/granulosa cells, is enabled by the presence of a network of cell-to-cell communication generated by gap junctions. Connexin 43 (Cx43) is the most abundant gap junction protein expressed by the ovarian follicle. The expression of Cx43 is subjected to the control of gonadotropins as follows: follicle-stimulating hormone (FSH) up regulates whereas LH (LH) down regulates its levels. The aim of this study was to explore the mechanism by which LH reduces the levels of Cx43 and to identify the signal transduction pathway involved in this process. The effect of LH was studied in vitro using isolated intact ovarian follicles. The possible mediators of LH-induced Cx43 down regulation were examined by incubating the follicles with LH in the presence or absence of inhibitors of protein kinase A (PKA) and of mitogen activated protein kinase (MAPK) signaling pathways. Our experiments revealed a 3 h half-life of Cx43 in both control and LH treated follicles, suggesting that LH did not affect the rate of Cx43 degradation. We further demonstrated that the level of Cx43 mRNA was not significantly influenced by this gonadotropin. However, upon LH administration [35S]methionine incorporation into Cx43 protein was remarkably reduced. The LH-induced arrest of Cx43 synthesis was counteracted by inhibitors of both the PKA and the MAPK cascades. We show herein that LH inhibits Cx43 expression by reducing its rate of translation and that this effect is mediated by both PKA and MAPK.
Key words: Connexin 43 • LH • translation • PKA • MAPK




This article has been cited by other articles:


Home page
 Biol. Reprod.Home page
S. Sela-Abramovich, D. Galiani, N. Nevo, and N. Dekel
Inhibition of Rat Oocyte Maturation and Ovulation by Nitric Oxide: Mechanism of Action
Biol Reprod, June 1, 2008; 78(6): 1111 - 1118.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Endocrinol.Home page
S. Panigone, M. Hsieh, M. Fu, L. Persani, and M. Conti
Luteinizing Hormone Signaling in Preovulatory Follicles Involves Early Activation of the Epidermal Growth Factor Receptor Pathway
Mol. Endocrinol., April 1, 2008; 22(4): 924 - 936.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Endocrinol.Home page
C.-G. Liang, Y.-Q. Su, H.-Y. Fan, H. Schatten, and Q.-Y. Sun
Mechanisms Regulating Oocyte Meiotic Resumption: Roles of Mitogen-Activated Protein Kinase
Mol. Endocrinol., September 1, 2007; 21(9): 2037 - 2055.
[Abstract] [Full Text] [PDF]

Home page
 Hum Reprod UpdateHome page
D. L. Russell and R. L. Robker
Molecular mechanisms of ovulation: co-ordination through the cumulus complex
Hum. Reprod. Update, May 1, 2007; 13(3): 289 - 312.
[Abstract] [Full Text] [PDF]

Home page
 Biol. Reprod.Home page
Y.-Q. Su, M. Nyegaard, M. T. Overgaard, J. Qiao, and L. C. Giudice
Participation of Mitogen-Activated Protein Kinase in Luteinizing Hormone-Induced Differential Regulation of Steroidogenesis and Steroidogenic Gene Expression in Mural and Cumulus Granulosa Cells of Mouse Preovulatory Follicles
Biol Reprod, December 1, 2006; 75(6): 859 - 867.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
M. Tsai-Turton and U. Luderer
Gonadotropin regulation of glutamate cysteine ligase catalytic and modifier subunit expression in rat ovary is subunit and follicle stage specific
Am J Physiol Endocrinol Metab, September 1, 2005; 289(3): E391 - E402.
[Abstract] [Full Text] [PDF]

Home page
 Nucleic Acids ResHome page
I. Pfeifer, C. Anderson, R. Werner, and E. Oltra
Redefining the structure of the mouse connexin43 gene: selective promoter usage and alternative splicing mechanisms yield transcripts with different translational efficiencies
Nucleic Acids Res., August 24, 2004; 32(15): 4550 - 4562.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 2003 by The Endocrine Society