![]() |
|
|
Vol. 9, Issue 6, 1479-1494, June 1998
and CCAAT/Enhancer Binding Protein
Isoform Synthesis in Control and LPS-Treated Livers
Department of Human Biological Chemistry and Genetics, University
of Texas Medical Branch, Galveston, Texas 77551
The CCAAT/enhancer binding protein
(C/EBP
) and
CCAAT/enhancer binding protein
(C/EBP
) mRNAs are templates for
the differential translation of several isoforms.
Immunoblotting detects C/EBP
s with molecular masses
of 42, 38, 30, and 20 kDa and C/EBP
s of 35, 20, and ~8.5 kDa. The
DNA-binding activities and pool levels of p42C/EBP
and
p30C/EBP
in control nuclear extracts decrease
significantly whereas the binding activity and protein levels of the
20-kDa isoforms increase dramatically with LPS treatment. Our studies
suggest that the LPS response involves alternative translational
initiation at specific in-frame AUGs, producing specific C/EBP
and
C/EBP
isoform patterns. We propose that alternative translational
initiation occurs by a leaky ribosomal scanning mechanism. We find that
nuclear extracts from normal aged mouse livers have decreased
p42C/EBP
levels and binding activity, whereas those of
p20C/EBP
and p20C/EBP
are increased.
However, translation of 42-kDa C/EBP
is not down-regulated on
polysomes, suggesting that aging may affect its nuclear translocation. Furthermore, recovery of the C/EBP
- and C/EBP
-binding activities and pool levels from an LPS challenge is delayed significantly in aged
mouse livers. Thus, aged livers have altered steady-state levels of
C/EBP
and C/EBP
isoforms. This result suggests that normal aging
liver exhibits characteristics of chronic stress and a severe inability
to recover from an inflammatory challenge.
This article has been cited by other articles:
![]() |
C. R. Gomez, C. Acuna-Castillo, C. Perez, E. Leiva-Salcedo, D. M. Riquelme, G. Ordenes, K. Oshima, M. Aravena, V. I. Perez, S. Nishimura, et al. Diminished Acute Phase Response and Increased Hepatic Inflammation of Aged Rats in Response to Intraperitoneal Injection of Lipopolysaccharide J Gerontol A Biol Sci Med Sci, December 1, 2008; 63(12): 1299 - 1306. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Rutkute, R. H. Asmis, and M. N. Nikolova-Karakashian Regulation of neutral sphingomyelinase-2 by GSH: a new insight to the role of oxidative stress in aging-associated inflammation J. Lipid Res., November 1, 2007; 48(11): 2443 - 2452. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.-C. Hsieh and J. Papaconstantinou Thioredoxin-ASK1 complex levels regulate ROS-mediated p38 MAPK pathway activity in livers of aged and long-lived Snell dwarf mice FASEB J, February 1, 2006; 20(2): 259 - 268. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. V. Giltiay, A. A. Karakashian, A. P. Alimov, S. Ligthle, and M. N. Nikolova-Karakashian Ceramide- and ERK-dependent pathway for the activation of CCAAT/enhancer binding protein by interleukin-1{beta} in hepatocytes J. Lipid Res., November 1, 2005; 46(11): 2497 - 2505. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. P. Martinez-Jimenez, M. J. Gomez-Lechon, J. V. Castell, and R. Jover Transcriptional Regulation of the Human Hepatic CYP3A4: Identification of a New Distal Enhancer Region Responsive to CCAAT/Enhancer-Binding Protein {beta} Isoforms (Liver Activating Protein and Liver Inhibitory Protein) Mol. Pharmacol., June 1, 2005; 67(6): 2088 - 2101. [Abstract] [Full Text] [PDF] |
||||
![]() |
K.-y. Yeh, M. Yeh, and J. Glass Hepcidin regulation of ferroportin 1 expression in the liver and intestine of the rat Am J Physiol Gastrointest Liver Physiol, March 1, 2004; 286(3): G385 - G394. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Gangneux, M. Daveau, M. Hiron, C. Derambure, J. Papaconstantinou, and J.-P. Salier The inflammation-induced down-regulation of plasma Fetuin-A ({alpha}2HS-Glycoprotein) in liver results from the loss of interaction between long C/EBP isoforms at two neighbouring binding sites Nucleic Acids Res., October 15, 2003; 31(20): 5957 - 5970. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Xiong, C.-C. Hsieh, A. J. Kurtz, J. P. Rabek, and J. Papaconstantinou Regulation of CCAAT/enhancer-binding protein-{beta} isoform synthesis by alternative translational initiation at multiple AUG start sites Nucleic Acids Res., July 15, 2001; 29(14): 3087 - 3098. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Karagiannides, T. Tchkonia, D. E. Dobson, C. M. Steppan, P. Cummins, G. Chan, K. Salvatori, M. Hadzopoulou-Cladaras, and J. L. Kirkland Altered expression of C/EBP family members results in decreased adipogenesis with aging Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2001; 280(6): R1772 - R1780. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Hirai, D. Radisky, R. Boudreau, M. Simian, M. E. Stevens, Y. Oka, K. Takebe, S. Niwa, and M. J. Bissell Epimorphin Mediates Mammary Luminal Morphogenesis through Control of C/EBP{beta} J. Cell Biol., May 14, 2001; 153(4): 785 - 794. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. M. Martin, B. M. Willardson, G. F. Burton, C. R. White, J. N. McLaughlin, S. M. Bray, J. W. Ogilvie Jr., and T. S. Elton Human Angiotensin II Type 1 Receptor Isoforms Encoded by Messenger RNA Splice Variants Are Functionally Distinct Mol. Endocrinol., February 1, 2001; 15(2): 281 - 293. [Abstract] [Full Text] |
||||
![]() |
C. S. Song, M. H. Jung, P. C. Supakar, B. Chatterjee, and A. K. Roy Negative Regulation of the Androgen Receptor Gene Promoter by NFI and an Adjacently Located Multiprotein-Binding Site Mol. Endocrinol., September 1, 1999; 13(9): 1487 - 1496. [Abstract] [Full Text] |
||||
![]() |
A. L. Welm, N. A. Timchenko, and G. J. Darlington C/EBPalpha Regulates Generation of C/EBPbeta Isoforms through Activation of Specific Proteolytic Cleavage Mol. Cell. Biol., March 1, 1999; 19(3): 1695 - 1704. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. L. Burgess-Beusse and G. J. Darlington C/EBPalpha Is Critical for the Neonatal Acute-Phase Response to Inflammation Mol. Cell. Biol., December 1, 1998; 18(12): 7269 - 7277. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. L. Welm, S. L. Mackey, L. T. Timchenko, G. J. Darlington, and N. A. Timchenko Translational Induction of Liver-enriched Transcriptional Inhibitory Protein during Acute Phase Response Leads to Repression of CCAAT/Enhancer Binding Protein alpha mRNA J. Biol. Chem., August 25, 2000; 275(35): 27406 - 27413. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Baer and P. F. Johnson Generation of Truncated C/EBPbeta Isoforms by in Vitro Proteolysis J. Biol. Chem., August 18, 2000; 275(34): 26582 - 26590. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Saito and J. Papaconstantinou Age-associated Differences in Cardiovascular Inflammatory Gene Induction during Endotoxic Stress J. Biol. Chem., July 27, 2001; 276(31): 29307 - 29312. [Abstract] [Full Text] [PDF] |
||||