help button home button Endocrine Society Molecular Endocrinology ENDO 08 Sessions Library
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 Xu, S.
Right arrow Articles by Cobb, M. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Xu, S.
Right arrow Articles by Cobb, M. H.
Molecular Endocrinology 11 (11): 1618-1625
Copyright © 1997 by The Endocrine Society

Differential Regulation of Mitogen-Activated Protein/ERK Kinase (MEK)1 and MEK2 and Activation by a Ras-Independent Mechanism

Shuichan Xu, Shih Khoo1, Alphonsus Dang, Sarah Witt, Vuong Do, Erzhen Zhen, Erik M. Schaefer and Melanie H. Cobb

University of Texas Southwestern Medical Center (S.X., S.K., A.D., S.W., V.D., E.Z., M.H.C.), Department of Pharmacology, Dallas, Texas 75235-9041,
Promega Corporation (E.M.S.), Madison, Wisconsin 53711

Mitogen-activated protein (MAP)/ERK kinase (MEK) 1 and MEK2 are the upstream activators of the MAP kinases, ERK1 and ERK2. MEK1 and MEK2 are ~85% identical in sequence but have unique inserts in their C-terminal domains. MEK isoform-specific antibodies were used to examine expression and regulation of each enzyme. MEK1 and MEK2 were expressed in approximately equal amounts in several cell lines; in some, MEK1 was present in slight excess. Activation of tyrosine kinase-containing receptors, heterotrimeric G proteins, and protein kinase C enhanced the activities of both MEK isoforms in 293 and PC12 cells. AlF4- stimulated both MEK1 and MEK2 in PC12 cells expressing a dominant interfering Ras mutant that prevents nerve growth factor-dependent activation of the cascade. Carbachol also stimulated the pathway in these cells. Thus, in addition to their ability to activate Ras/Raf and the downstream ERK pathway, heterotrimeric G proteins also appear to trigger a Ras-independent mechanism to regulate this kinase cascade. In U373, Chinese hamster ovary (CHO), and INS-1 cells, MEK1 was activated by regulators of ERKs, while MEK2 was not. These data suggest that, like the MAP kinases ERK1 and ERK2, in some cell settings the two similar MEK isoforms are differentially regulated.




This article has been cited by other articles:


Home page
 DevelopmentHome page
V. Nadeau, S. Guillemette, L.-F. Belanger, O. Jacob, S. Roy, and J. Charron
Map2k1 and Map2k2 genes contribute to the normal development of syncytiotrophoblasts during placentation
Development, April 15, 2009; 136(8): 1363 - 1374.
[Abstract] [Full Text] [PDF]

Home page
 DevelopmentHome page
V. Bissonauth, S. Roy, M. Gravel, S. Guillemette, and J. Charron
Requirement for Map2k1 (Mek1) in extra-embryonic ectoderm during placentogenesis
Development, September 1, 2006; 133(17): 3429 - 3440.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
S. Ussar and T. Voss
MEK1 and MEK2, Different Regulators of the G1/S Transition
J. Biol. Chem., October 15, 2004; 279(42): 43861 - 43869.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
D. Arnette, T. B. Gibson, M. C. Lawrence, B. January, S. Khoo, K. McGlynn, C. A. Vanderbilt, and M. H. Cobb
Regulation of ERK1 and ERK2 by Glucose and Peptide Hormones in Pancreatic {beta} Cells
J. Biol. Chem., August 29, 2003; 278(35): 32517 - 32525.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
L. E. Bullard, X. Qi, and J. S. Penn
Role for Extracellular Signal-Responsive Kinase-1 and -2 in Retinal Angiogenesis
Invest. Ophthalmol. Vis. Sci., April 1, 2003; 44(4): 1722 - 1731.
[Abstract] [Full Text] [PDF]

Home page
 DiabetesHome page
M. K. Lingohr, L. M. Dickson, J. F. McCuaig, S. R. Hugl, D. R. Twardzik, and C. J. Rhodes
Activation of IRS-2--Mediated Signal Transduction by IGF-1, but not TGF-{alpha} or EGF, Augments Pancreatic {beta}-Cell Proliferation
Diabetes, April 1, 2002; 51(4): 966 - 976.
[Abstract] [Full Text] [PDF]

Home page
 EndocrinologyHome page
J. Eichhorn, A. G. Kayali, L. Resor, D. A. Austin, D. W. Rose, and N. J. G. Webster
PLC-{gamma}1 Enzyme Activity Is Required for Insulin-Induced DNA Synthesis
Endocrinology, February 1, 2002; 143(2): 655 - 664.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
M. E. Bates, V. L. Green, and P. J. Bertics
ERK1 and ERK2 Activation by Chemotactic Factors in Human Eosinophils Is Interleukin 5-dependent and Contributes to Leukotriene C4 Biosynthesis
J. Biol. Chem., April 6, 2000; 275(15): 10968 - 10975.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Biol. CellHome page
V. Antonelli, F. Bernasconi, Y. H. Wong, and L. Vallar
Activation of B-Raf and Regulation of the Mitogen-activated Protein Kinase Pathway by the Go alpha chain
Mol. Biol. Cell, April 1, 2000; 11(4): 1129 - 1142.
[Abstract] [Full Text]

Home page
 Mol. Endocrinol.Home page
T. J. Pircher, H. Petersen, J.-A. Gustafsson, and L.-A. Haldosén
Extracellular Signal-Regulated Kinase (ERK) Interacts with Signal Transducer and Activator of Transcription (STAT) 5a
Mol. Endocrinol., April 1, 1999; 13(4): 555 - 565.
[Abstract] [Full Text]


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 © 1997 by The Endocrine Society