![]()
|
|
||||||||
J. Biol. Chem., Vol. 276, Issue 2, 1545-1554, January 12, 2001
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
and
and ERK Activation*
§¶,
§
,
,
,

, and
From the The high molecular weight
(HMW) fibroblast growth factor (FGF)-2 isoform of 210 amino
acids initiated at a CUG start codon possesses a nuclear localization
sequence and is not secreted. In contrast, the low molecular weight
(LMW) isoform of 155 amino acids initiated at the AUG start codon can
be secreted and activates the cell surface FGF receptors. The two
isoforms possess different biological properties; however, little is
known about the intracrine regulatory mechanisms involved in the
biological effects of the HMW FGF-2 isoform. Using pancreatic cells
stably transfected with cDNAs leading to the expression of either
the HMW FGF-2 (A3 cells) or the LMW form (A5 cells), we provide
evidence that the two FGF-2 isoforms differentially modulate PKC
levels. The LMW FGF-2 up-regulated the PKC
INSERM U 531, Institut Louis Bugnard, CHU
Rangueil Bat L 3, 31403 Toulouse Cedex 4, France and ** Division of
Endocrinology, Diabetes and Metabolism, University of California,
Irvine, California 92697
levels by 1.6-fold; by
contrast the HMW isoform down-regulated the level of this PKC isotype
by about 3-fold and increased the amount of PKC
by 1.7-fold. PKC
mRNAs were also modified, suggesting that PKC expression was
regulated at a pretranslational level. Additionally, expression of
different levels of the HMW FGF-2 with an inducible expression system
confirmed the role of this isoform on PKC
and
expressions.
Increased activation of ERK-1 and -2 was also observed in cells
expressing the HMW FGF-2. By using different PKC inhibitors and a
dominant negative PKC
, it was found that ERK activation was PKC
-dependent. These data indicate that expression of HMW
FGF-2 can modify PKC levels by acting at the intracellular level and
that the overexpression of PKC
induces ERK-1/2 activation. The
expression of a dominant negative FGFR1 did not reduce ERK-1/2
activation by the HMW FGF-2, suggesting that ERK activation does not
require FGFR activity. The signaling cascade downstream of ERK might be
involved in the known mitogenic effect exerted by this FGF-2 isoform.
Supported by a long term fellowship from the Ligue Contre le
Cancer du Tarn and the Fondation pour la Recherche Médicale.

To whom correspondence should be addressed: INSERM U 531, ILB,
CHU Rangueil Bat L3 31054 Toulouse Cédex, France. Tel.:
33-05-61-32-24-04; Fax: 33-05-61-32-24-03; E-mail:
Francois.Clemente@rangueil.inserm.fr.
This article has been cited by other articles:
![]() |
S. L. House, S. J. Melhorn, G. Newman, T. Doetschman, and J. E. J. Schultz The protein kinase C pathway mediates cardioprotection induced by cardiac-specific overexpression of fibroblast growth factor-2 Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H354 - H365. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Dvorak, D. Dvorakova, S. Koskova, M. Vodinska, M. Najvirtova, D. Krekac, and A. Hampl Expression and Potential Role of Fibroblast Growth Factor 2 and Its Receptors in Human Embryonic Stem Cells Stem Cells, September 1, 2005; 23(8): 1200 - 1211. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. V. Wesley, M. McGroarty, and A. Homoyouni Dipeptidyl Peptidase Inhibits Malignant Phenotype of Prostate Cancer Cells by Blocking Basic Fibroblast Growth Factor Signaling Pathway Cancer Res., February 15, 2005; 65(4): 1325 - 1334. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Zhan, D. Yu, J. Liu, J. Hannay, and R. E. Pollock Transcriptional Repression of Protein Kinase C{alpha} via Sp1 by Wild Type p53 Is Involved in Inhibition of Multidrug Resistance 1 P-Glycoprotein Phosphorylation J. Biol. Chem., February 11, 2005; 280(6): 4825 - 4833. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Hortala, G. Ferjoux, A. Estival, C. Bertrand, S. Schulz, L. Pradayrol, C. Susini, and F. Clemente Inhibitory Role of the Somatostatin Receptor SST2 on the Intracrine-regulated Cell Proliferation Induced by the 210-Amino Acid Fibroblast Growth Factor-2 Isoform: IMPLICATION OF JAK2 J. Biol. Chem., May 30, 2003; 278(23): 20574 - 20581. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |