Biochem. Soc. Symp. 70, 95–106
(Printed in Great Britain)
© 2003 Biochemical Society
Control of the expression of
inflammatory response genes
Jeremy Saklatvala1,Jonathan Dean and Andrew Clark
Kennedy Institute of Rheumatology Division, Imperial College London,
1 Aspenlea Rd, London W6 8LH, U.K.
The expression of genes involved in the inflammatory response is con-
trolled both transcriptionally and post-transcriptionally. Primary inflammatory
stimuli, such as microbial products and the cytokines interleukin-1 (IL-1) and
tumour necrosis factor ? (TNF?), act through receptors of either the Toll and
IL-1 receptor (TIR) family or the TNF receptor family. These cause changes in
gene expression by activating four major intracellular signalling pathways that
are cascades of protein kinases: namely the three mitogen-activated protein
kinase (MAPK) pathways, and the pathway leading to activation of the transcrip-
tion factor nuclear factor ?B (NF?B). The pathways directly activate and induce
the expression of a limited set of transcription factors which promote the tran-
scription of inflammatory response genes. Many of the mRNAs are unstable, and
are stabilized by the p38 MAPK pathway. Instability is mediated by clusters of
the AUUUA motif in the 3? untranslated regions of the mRNAs. Control of
mRNA stability provides a means of increasing the amplitude of a response and
allows rapid adjustment of mRNA levels. Not all mRNAs stabilized by p38 con-
tain AUUUA clusters; for example, matrix metalloproteinase-1 and -3 mRNAs
lack these clusters, but are stabilized. Inflammatory gene expression is inhibited
by glucocorticoids. These suppress MAPK signalling by inducing a MAPK
phosphatase. This may be a significant mechanism additional to that by which
the glucocorticoid receptor interferes with transcription factors.
Introduction:the inflammatory response
Proteinases mediate the tissue destruction that is an important feature of
chronic inflammatory diseases such as rheumatoid arthritis. The extensive
damage to articular cartilage, bone, tendons and ligaments that occurs in
rheumatoid disease has been attributed to multiple attack by a variety of pro-
1To whom correspondence should be addressed (e-mail email@example.com).
teinases that are the subject of other contributions to this symposium; these
include the matrix metalloproteinases (MMPs), the aggrecanases and the lyso-
somal proteinases, particularly those of osteoclasts, and the neutral serine
proteinases of polymorphonuclear leucocytes. The synthesis of a number of
these enzymes, for example MMPs-1, -3, -8 and -13 and the aggrecanases
ADAMTS-1 and ADAMTS-4 [where ADAMTS denotes ADAM (a disinte-
grin and metalloproteinase) with thrombospondin motifs], is strongly induced
by inflammatory stimuli. The purpose of this review is to summarize current
knowledge of how the expression of the many proteins of the inflammatory
response, including the proteinases, is controlled.
Inflammation is the response of tissues to injury. It is a defence mechanism
against microbial invasion, its immediate function being to attract leucocytes
from the circulation to sites of tissue damage. Incoming leucocytes deal with the
threat and the inflammation resolves. If there is tissue damage, dead cells and
their associated matrix are removed, and repair takes place by proliferation of
fibroblasts and capillaries to form granulation tissue. This eventually forms a
fibrous scar. In chronic inflammatory diseases of unknown cause, such as
rheumatoid arthritis, the inflammation fails to resolve appropriately and what
should be a repair process of limited duration becomes invasive and destructive.
Over the last 20 years there has been a huge expansion in knowledge about
the complex cellular processes of inflammation and their molecular mechanisms.
Important advances have been made in understanding the signals that attract
leucocytes and the molecular interactions that guide them. Insights have been
gained into the microbicidal and phagocytic mechanisms of leucocytes. And last
but not least, complex controlling networks of cytokines and growth factors
have been discovered. These chemical messengers control not only the early
events of inflammation, but also the later reparative phase of cellular prolifera-
tion, as well as the final stage of production of collagen to form scar tissue.
Inflammatory receptor signalling
The primary initiating stimuli of inflammation signal through either of
two major classes of cell surface receptor: the Toll and interleukin-1 (IL-1)
receptor (TIR) family and the tumour necrosis factor (TNF) receptor family.
These are unrelated, but both types of receptor activate a common set of four
well characterized intracellular signalling pathways. These are the protein kinase
system that leads to the activation of the transcriptional regulator nuclear factor
?B (NF?B), and the three mitogen-activated protein kinase (MAPK) cascades.
When the receptors bind their ligand, there is oligomerization that creates the
signal. For example, the IL-1 receptor forms heterodimers with an accessory
protein (Figure 1). TNF is a trimer and induces trimerization of its receptor. The
intracellular parts of these dimers and trimers interact with adaptor molecules to
form signalling complexes that activate the downstream pathways .
The Toll-like receptors (TLRs) of mammalian cells were discovered rela-
tively recently , and have provided us with a unified view of the innate
immune response and inflammation. The cytoplasmic part of the type I IL-1
receptor (the signalling receptor) is a homologue of Drosophila Toll, a trans-
© 2003 Biochemical Society
96J. Saklatvala, J. Dean and A. Clark
membrane protein involved in dorso-ventral patterning in embryogenesis, and
in anti-fungal responses. Toll is at the head of a signalling cascade analogous to
the mammalian NF?B pathway. NF?B regulates many inflammatory and
immune response genes. Mammalian homologues of Toll, called TLRs, detect
and signal the presence of microbial products and are at the centre of the innate
immune response. TLR4 is crucial for recognition of bacterial lipopolysaccha-
ride (LPS), TLR2 for detecting peptidoglycans and bacterial lipopeptides,
TLR3 senses double-stranded RNA, TLR5 detects bacterial flagellin and TLR9
regognizes bacterial DNA containing unmethylated CpG dinucleotides. There
are ten TLRs, but not all of their recognition targets are known as yet.
The TLR-mediated innate immune response is phylogenetically ancient,
and permits rapid responses to invading pathogens. Induction of IL-1 and
Control of inflammatory response gene expression97
© 2003 Biochemical Society
Type I IL-1R
Figure 1 Early signalling events of the type I IL-1 receptor. The type I
IL-1 receptor (IL-1R) in the cell membrane binds IL-1 and interacts with the IL-
1R accessory (Acc) protein. The adaptor MyD88 interacts with the complex
and allows IRAK to dock transiently. IRAK becomes hyperphosphorylated and
dissociates, interacting with TRAF6. This complex activates the downstream
protein kinases. The MAPK (MK) cascades are shown: ERK, JNK and p38
MAPK. These are activated by MKKs, which in turn are activated by MKK
kinases (MKKKs). Transforming growth factor ?-activated kinase (TAK) is a
candidate MKKK in the IL-1 signalling pathway. The downstream kinases MAP-
KAPK-1 and -2 phosphorylate ribosomal protein S6 (RS6) and Hsp27
respectively. I?B is the inhibitor of NF?B and IKK is I?B kinase. Elk1, ATF2, c-
Jun, MEF2C, CHOP and CREB (cAMP response element-binding protein) are
transcription factors that become phosphorylated.
TNF? is an early event in this process. Because these pro-inflammatory
cytokines share intracellular signalling pathways with the TLRs, they serve to
amplify the innate immune response. The acquired response evolved later to
enable specific rapid recognition of micro-organisms and to focus powerful
microbicidal responses. The two processes are closely linked, with the innate
response contributing to the generation of acquired immunity, and the acquired
immune system triggering inflammatory responses as an effector mechanism.
Figure 1 shows a simple version of the current model for signalling by the
IL-1 receptor. The signalling complex involves formation of a heterodimer
between the receptor and the IL-1 receptor accessory protein. The intracellular
parts of the heterodimer interact with the adaptor protein MyD88. IL-1 recep-
tor-associated kinase 1 (IRAK1) and IRAK4 dock on to the complex. IRAK1
becomes hyperphosphorylated during a transient association with the receptor
and then interacts with TNF receptor-associated factor 6 (TRAF6) . TRAF6
activates the downstream cascades via MAPK kinase kinases.
The TLRs create similar signalling complexes, but there are additional
and/or alternative adaptor proteins involved, giving rise to variations in down-
stream signalling. Examples include the recently described MyD88-like
adaptor (MAL) or TIRAP [4,5]. TRAF6 is essential for TIR signalling, and is
also implicated in signalling by IL-17 and CD40, which are not members of the
TIR family .
At the bottom of the cascades are the proteins that regulate expression of
the inflammatory response genes: until recently these were mainly considered
to act on transcription, but some act post-transcriptionally, particularly in the
control of mRNA stability. Many of the proteins of the inflammatory response
have potent effects and need to be tightly controlled. It is therefore not surpris-
ing that there are complex regulatory mechanisms that permit rapid and
substantial changes in expression.
Figure 2 shows a diagram of the proximal promoter of the cyclo-oxyge-
nase-2 (COX-2) gene, a typical inflammatory response gene. COX-2 is thought
to be responsible for much of the increased prostaglandin production at inflam-
matory sites, and is the target of many anti-inflammatory drugs. Prostaglandins
have important effects on local blood flow and perception of pain.
The COX-2 promoter has binding sites for transcription factors that are
typical for inflammatory response genes: NF?B, AP1 (activator protein 1),
C/EBP? (CAAT/enhancer-binding protein; also called NFIL-6), Ets and
CREB (cAMP response element-binding protein). NF?B lies at the bottom of
a specific activation cascade (Figure 1), and the majority of inflammatory
response genes are NF?B-dependent. AP1 sites bind various heterodimers and
homodimers of the c-Jun and c-Fos families, and ATF2 (activating transcrip-
© 2003 Biochemical Society
98J. Saklatvala, J. Dean and A. Clark
tion factor-2). The MAPK family member c-Jun N-terminal kinase (JNK)
phosphorylates and transcriptionally activates c-Jun and ATF2. Ets family
members such as [Elk1 and SAP-1 (serum response factor accessory protein-1),
as well as C/EBP?, are activated by the original MAPK, extracellular-signal-
regulated kinase (ERK) .
There is an extensive literature on the regulation of transcription factors
by these signalling pathways, and some generalizations can be made (see  for
a review). First, binding sites for the same limited set of transcription factors
are usually found in the proximal promoters of inflammatory genes. Secondly,
there are often multiple sites, and their arrangements vary widely. Thirdly,
there may be sites for binding of transcription factors activated by other
cytokine pathways (e.g. by interferons or by IL-6 and its related cytokines).
Fourthly, the transcription factors act in concert to promote the binding of
cofactors such as histone acetylases and RNA polymerase. Fifthly, the NF?B,
ERK and JNK pathways are all probably crucial for the transcription of
inflammatory response genes. The transcriptional role of the p38 MAPK cas-
cade is less well understood, but it is involved in the regulation of NF?B [6,7].
Finally, the transcription factors may be activated directly by phosphorylation
by the signalling pathways, or their expression may be induced. Examples of
the former are NF?B, which translocates from cytoplasm to nucleus on cell
activation, and AP1-binding proteins such as c-Jun, which are phosphorylated
and so transcriptionally activated upon cell stimulation. Examples of the latter
are induction of expression of c-Jun and c-Fos, which then secondarily activate,
or sustain the activation of, inflammatory genes.
The stability of the mRNA transcripts of inflammatory response proteins
is regulated. Many contain AU-rich elements (AREs) in their 3? untranslated
Control of inflammatory response gene expression 99
© 2003 Biochemical Society
Figure 2 The human COX-2 promoter. The beads represent transcrip-
tion factor binding sites in the proximal promoter. ‘AP1’ indicates sites for
activator AP1 complexes (e.g. c-Fos/c-Jun/ATF2 heterodimers). C/EBP is
CAAT/enhancer-binding protein (C/EBP? is also called nuclear factor-IL-6).
CRE is the cAMP response element that binds CRE-binding protein (CREB). Ets
is a transcription factor family whose members include Elk1 and SAP-1 (serum
response factor accessory protein-1), which are phosphorylated by MAPKs.
See Figure 1 for activating phosphorylation of the transcription factors.
region (UTR). These AREs characteristically comprise clusters of the motif
AUUUA and confer instability . Activity in the p38 MAPK pathway coun-
ters this destabilizing effect and so stabilizes the mRNA in question. This was
first shown for COX-2 mRNA [9,10], IL-3 mRNA , IL-6 mRNA , IL-
8 mRNA , and later TNF? mRNA  and a number of others. The
mechanism has been investigated by using a tetracycline-regulated post-tran-
scriptional reporter plasmid [14–16]. The COX-2 destabilizing element was
localized to a cluster of six AUUUA repeats just 3? of the open reading frame.
This destabilizing element could be counteracted by activating the p38 MAPK
pathway, and this was dependent upon the downstream kinase MAPK-acti-
vated protein kinase-2 (MAPKAPK-2). The relevant substrate(s) of
MAPKAPK-2 remain(s) to be identified.
The stability of an mRNA is closely related to its translation. In some situa-
tions the p38 MAPK pathway appears to be needed for translation of an mRNA,
because blocking the pathway inhibits production of protein without causing dis-
appearance of the mRNA. For example, blocking p38 MAPK in murine
macrophages stimulated with LPS almost completely inhibits production of
TNF? protein, but only partially inhibits induction of its mRNA . LPS
induces TNF? mRNA in the MAPKAPK-2 knockout mouse, but little or no
protein is produced . It is likely that blocking the p38 pathway uncouples
translation, and, depending on the mRNA species and the capacity of the degrada-
tive machinery, the uncoupled mRNA may be rapidly degraded or may persist.
The regulation of mRNA stability has three functions. First, it provides
additional amplification of a response; secondly, it enables rapid adjustment of
mRNA levels; and thirdly, it allows rapid termination of the production of a
protein whose expression is no longer required.
It is too early to say how general the stabilization of inflammatory
mRNAs by the p38 cascade is. It is also not known to what extent other sig-
nalling pathways are involved. The JNK pathway stabilizes IL-2 mRNA ,
and phorbol ester that activates protein kinase C and the ERK pathway stabi-
lizes granulocyte/macrophage colony-stimulating factor mRNA . The
phosphoinositide 3-kinase pathway affects IL-3 mRNA stability .
The presence of an ARE in the 3? UTR of an mRNA does not necessarily
confer regulation by p38 MAPK. The 3? UTR of the gene encoding c-Fos con-
tains a typical cluster of AU repeats which, when placed in a reporter, confer
instability and can be stabilized in a p38-dependent manner . However, c-
Fos mRNA is not stabilized by p38. This is probably because an instability
determinant in the coding sequence overrides any effect of the ARE .
Another example of an unstable oncogene mRNA not stabilized by p38 acting
on the 3? UTR ARE is c-Myc .
The mechanism by which mRNA stability is controlled via AREs is
unknown. Several heterogeneous nuclear ribonucleoproteins bind tightly to
AREs, including the prototype AU-binding protein AUF1 [22,23], its close rela-
tive CARG-box-binding factor-A , HuR  and tristetraprolin (TTP) .
Of these, only TTP definitely plays a role in cytokine expression. It is a member
of a family of early-response genes, and TTP knockout mice have a diffuse
inflammatory syndrome, including an arthritis . The absence of TTP results
© 2003 Biochemical Society
100 J. Saklatvala, J. Dean and A. Clark
in overproduction of TNF? (and probably other cytokines) due to an increased
half-life of its mRNA. TTP binds to the ARE and destabilizes the mRNA .
TTP is not expressed in HeLa cells, which have been used for the post-
transcriptional reporter studies, so the basic p38-dependent mechanism is
independent of it. Interestingly, the expression of TTP (in macrophages) is p38-
dependent . Thus TTP is induced by LPS (and probably generally by
inflammatory stimuli) and is a negative regulator of cytokine expression. It
appears to represent another level of regulation on top of the basic destabilizing
mechanism controlled by p38. It is paradoxical that p38 MAPK should have a
stabilizing role but also mediate the expression of a destabilizing protein such
It is possible that the p38 MAPK pathway directly regulates the proteins
that bind to the ARE. Figure 3 shows a current model of mRNA structure. The
poly(A)-binding protein binds the 3? poly(A) tail and eukaryotic initiation fac-
tor 4G, a component of the initiation complex that binds to the 5? cap
structure. This circularizes the mRNA and facilitates translation. The circular
structure is stable as long as the poly(A) tail is present. When it is lost, the
mRNA is degraded , probably mainly 3?→5? by the exosome, a large com-
plex comprising at least 10 exonucleases . In this model, ARE-binding
proteins could direct deadenylation and be under the control of the p38 path-
way. Alternatively, the p38 pathway may act on the decay machinery,
instructing it to disregard mRNAs ‘tagged’ by ARE-binding proteins. Decay
of mRNA also occurs due to the action of 5?→3? exonucleases following
decapping [31,32]. The significance of this pathway in mammalian cells and its
importance in the control of mRNA decay by AREs and p38 MAPK remains
to be established .
Control of inflammatory response gene expression 101
© 2003 Biochemical Society
Figure 3 Post-transcriptional regulation of gene expression. When
being translated, mRNA forms a circular structure because the poly(A)-binding
protein (PABP) binds both the 3? poly(A) tail and eukaryotic initiation factor
4G (eIF4G). eIF4G, eIF4A and eIF4E are a trimeric complex (eIF4F) which binds
to the 7-methylguanosine 5? cap structure (m7Gppp). Start (AUG) and stop
(UAG) codons are shown, and the 3? UTR contains an ARE which typically
might contain five or six copies of the motif AUUUA. ARE-binding proteins
(AREBPs) target the mRNA for degradation, and the p38 MAPK counteracts
Control of the MMPs
The expression of MMP-1 and MMP-3 is induced in cells of connective
tissue by inflammatory stimuli such as IL-1 and TNF, and by growth factors.
The MMP-1 promoter has an AP1 site that has been much studied [34,35].
There is also evidence that NF?B is involved in MMP-1 expression, because
there is an NF?B-binding site far upstream in the promoter region. In addition,
IL-1 may stabilize the mRNA via three AUUUA motifs . It is important to
stress that, in practice, an inflammatory stimulus such as IL-1 does not act
alone, but in conjunction with other cytokines, such as, for example, the IL-6
family (which they induce). The IL-6 family member oncostatin M synergizes
with IL-1 in the production and activation of MMP-1, and this phenomenon is
discussed in Chapter 11 by Cawston et al. in this volume.
Expression of both MMP-1 and MMP-3 in gingival and dermal fibrob-
lasts is strongly dependent on p38 MAPK activity . It was shown recently
that the p38 MAPK pathway stabilizes the MMP mRNAs . Activation of
the pathway by transfecting an active MAPK kinase 3 (MKK3) mutant (MKK3
is a p38 activator) stabilized the MMP-1 and MMP-3 mRNAs. This is interest-
ing and surprising, because neither MMP has a typical destabilizing,
p38-responsive ARE in its 3? UTR. The 3? UTR of MMP-3 has only a single
AUUUA motif, and that of MMP-1 has three which are dispersed . From
mapping experiments on the COX-2 ARE, we would not predict that these
MMP 3? UTR sequences would be regulated by p38 MAPK. Thus the pathway
may also stabilize mRNAs that do not have typical AREs. This implies that the
p38 MAPK cascade controls the stability of mRNA by mechanisms additional
to the recognition of AREs and their binding proteins, or that the latter also
recognize sequences other than AUUUA clusters.
Other proteinases regulated by inflammatory stimuli are ADAM family
members. ADAMTS-1 is up-regulated by LPS , and ADAMTS-4 (also
called aggrecanase 1) is up-regulated by IL-1 [40,41]. However, so far neither
transcriptional or post-transcriptional mechanisms of their regulation have
been reported. The control of MMP activation mechanisms by inflammatory
stimuli has yet to be explored. Urokinase-type plasminogen activator and plas-
minogen activator inhibitor 2 are both regulated by inflammatory stimuli .
Regulation of membrane-type MMPs in inflammation has not been reported.
Glucocorticoid suppression of inflammation
The expression of many genes of the inflammatory response is sup-
pressed by glucocorticoids, and this may be due in part to actions on the
intracellular signalling pathways used by inflammatory stimuli. Synthetic glu-
cocorticoids are used widely for anti-inflammatory therapy in diseases such as
rheumatoid arthritis, Crohn’s disease and asthma, and as immunosuppressants
in transplantation. They are also used in certain malignancies. Although very
potent in suppressing inflammation, they have a variety of highly undesirable
side effects that limit their use. These include osteoporosis, diabetes, cataracts,
© 2003 Biochemical Society
102J. Saklatvala, J. Dean and A. Clark
hypertension, the characteristic features of Cushing’s syndrome and suppres-
sion of the hypothalamic/pituitary/adrenal axis.
Physiologically, glucocorticoids are produced in increased amounts in
response to physical stress such as infection. The inflammatory cytokines and
microbial products act on the pituitary gland, via the hypothalamus, to stimu-
late the production of corticotropin (‘ACTH’), which stimulates the adrenal
cortex. The glucocorticoids produced act as a negative feedback on the produc-
tion of inflammatory cytokines and mediators.
Glucocorticoids act by binding to the glucocorticoid receptor, a tran-
scription factor that is a member of the nuclear receptor family . The
liganded glucocorticoid receptor binds as a dimer to target DNA sequences
called glucocorticoid response elements (GREs) in the promoter regions of
glucocorticoid-sensitive genes. While GRE-dependent genes are thought to
underlie some of the side effects of glucocorticoids (e.g. diabetes), none have
been identified that account for the profound anti-inflammatory actions of glu-
cocorticoids. Examples of inflammatory response proteins that are suppressed
by glucocorticoids are IL-1, TNF, chemokines, IL-6, COX-2, MMP-1 and
MMP-3. All are inhibited at the level of mRNA expression. One mechanism
behind this global suppression is transrepression, or transcriptional interfer-
ence [42,43]. The liganded glucocorticoid receptor, in addition to binding to
the GREs, also binds to AP1 and NF?B transcription factors, and in so doing
interferes with their transcriptional activity.
Glucocorticoids also have post-transcriptional effects on the expression
of genes of the inflammatory response: they destabilize the mRNAs of COX-2
and several cytokines. This is likely to be because they prevent the p38 MAPK-
mediated stabilization of mRNAs. We found that treating cells with
dexamethasone, a synthetic glucocorticoid, reversed the mRNA-stabilizing
effect of p38 MAPK . Furthermore, dexamethasone strongly inhibited the
activation of p38 MAPK and JNK by inflammatory stimuli. It had no effect on
the activation of MKK6 (the kinase upstream of p38) or on the downstream
kinase MAPKAPK-2. For these reasons, and because JNK and p38 have differ-
ent activators (see Figure 1), it seemed likely that dexamethasone was inducing
a molecule that countered the effect of the MKKs by maintaining the MAPKs
in their inactive, unphosphorylated state. A phosphatase was a good candidate.
MAPKs are inactivated by removal of either their threonine or tyrosine phos-
phates, so a large number of phosphatases potentially could be involved.
Among these are the MAPK phosphatases (MKPs)/dual-specificity phos-
phatases (DUSPs), of which more than 10 have been identified. Gene chip
experiments revealed that the major phosphatase induced by dexamethasone
was MKP1/DUSP1, and this was confirmed by Northern and Western blotting
. MKP1 is an early response gene that is transiently activated by very many
stimuli, and it has a preference for p38 MAPK and JNK over ERK . Most
interestingly, dexamethasone caused a sustained increase in the expression of
MKP1 – thus, within 1 h of dexamethasone treatment, and even after 24 h
exposure to the steroid, the protein was strongly induced . IL-1 itself
induces MKP1 transiently (Figure 4a). IL-1 causes two phases of p38 MAPK
activation (Figure 4b). An initial strong transient phase peaks at 30 min whose
Control of inflammatory response gene expression103
© 2003 Biochemical Society
subsidence corresponds with the induction of MKP1. By 2 h the transiently
induced MKP1 has gone, and IL-1-dependent p38 activation returns at a lower
level and is sustained. Adding dexamethasone together with IL-1 blunts the ini-
tial burst of signalling slightly as MKP1 is being induced, but the sustained
MKP1 expression caused by the dexamethasone prevents the second phase of
activation (Figure 4). It is important to point out that, in order to inhibit the
first peak of signalling, dexamethasone would need to be added 1–2 h prior to
IL-1 in order to induce expression of the phosphatase . Recently, overex-
pression of MKP1 in murine cells has been shown to inhibit cytokine
expression . It remains to be proved that MKP1 induction is the mechanism
by which glucocorticoids inhibit MAPK signalling, and is of physiological sig-
nificance for glucocorticoid action.
We are grateful to the Arthritis Research Campaign and the Medical Research
Council for their support.
Kracht, M. and Saklatvala, J. (2002) Cytokine 20, 91–106
Medzhitov, R. and Janeway, Jr, C.A. (2002) Science 296, 298–300
Cao, Z., Xiong, J., Takeuchi, M., Kurama, T. and Goeddel, D.V. (1996) Nature (London)
Fitzgerald, K.A., Palsson-McDermott, E.M., Bowie, A.G., Jefferies, C.A., Mansell, A.S.,
Brady, G., Brint, E., Dunne, A., Gray, P., Harte, M.T. et al. (2001) Nature (London) 413,
Horng, T., Barton, G.M. and Medzhitov, R. (2001) Nat. Immunol. 2, 835–841
Saccani, S., Pantano, S. and Natoli, G. (2002) Nat. Immunol. 3, 69–75
Vermeulen, L., De Wilde, G., Damme, P.V., Vanden Berghe, W. and Haegeman, G. (2003)
EMBO J. 22, 1313–1324
© 2003 Biochemical Society
104 J. Saklatvala, J. Dean and A. Clark
0 1h2h 4h24h8h 15?
Figure 4 Dexamethasone causes prolonged induction of MKP1 and
inhibits late-phase activation of p38 MAPK by IL-1. HeLa cells were
treated with IL-1 (10 ng/ml) or IL-1 plus dexamethasone (Dex; 1 ?M) for the
course of the experiment. (a) MKP1 was detected by Western blotting. (b) The
activity of p38 MAPK in the cells was measured at the indicated times by immuno-
precipitating it from cell lysates and incubating the precipitates with recombinant
MAPKAPK-2 substrate and ATP (10 ?M) containing [?-32P]ATP. Reaction
products were separated by SDS/PAGE, and the gel was autoradiographed
to show phosphorylated MAPKAPK-2 (MK2). From .
Shaw, G. and Kamen, R. (1986) Cell 46, 659–667
Ridley, S.H., Dean, J.L., Sarsfield, S.J., Brook, M., Clark, A.R. and Saklatvala, J. (1998)
FEBS Lett. 439, 75–80
Dean, J.L., Brook, M., Clark, A.R. and Saklatvala, J. (1999) J. Biol. Chem. 274, 264–269
Ming, X.F., Kaiser, M. and Moroni, C. (1998) EMBO J. 17, 6039–6048
Miyazawa, K., Mori, A., Miyata, H., Akahane, M., Ajisawa, Y. and Okudaira, H. (1998) J.
Biol. Chem. 273, 24832–24838
Holtmann, H., Winzen, R., Holland, P., Eickemeier, S., Hoffmann, E., Wallach, D.,
Malinin, N.L., Cooper, J.A., Resch, K. and Kracht, M. (1999) Mol. Cell. Biol. 19, 6742–6753
Brook, M., Sully, G., Clark, A.R. and Saklatvala, J. (2000) FEBS Lett. 483, 57–61
Lasa, M., Mahtani, K.R., Finch, A., Brewer, G., Saklatvala, J. and Clark, A.R. (2000) Mol.
Cell. Biol. 20, 4265–4274
Winzen, R., Kracht, M., Ritter, B., Wilhelm, A., Chen, C.Y.A., Shyu, A.B., Muller, M.,
Gaestel, M., Resch, K. and Holtmann, H. (1999) EMBO J. 18, 4969–4980
Prichett, W., Hand, A., Sheilds, J. and Dunnington, D. (1995) J. Inflamm. 45, 97–105
Kotlyarov, A., Neininger, A., Schubert, C., Eckert, R., Birchmeier, C., Volk, H.D. and
Gaestel, M. (1999) Nat. Cell Biol. 1, 94–97
Chen, C.Y., Del Gatto-Konczak, F., Wu, Z. and Karin, M. (1998) Science 280, 1945–1949
Ming, X.F., Stoecklin, G., Lu, M., Looser, R. and Moroni, C. (2001) Mol. Cell. Biol. 21,
Schiavi, S.C., Wellington, C.L., Shyu, A.B., Chen, C.Y., Greenberg, M.E. and Belasco, J.G.
(1994) J. Biol. Chem. 269, 3441–3448
Brewer, G. (1991) Mol. Cell. Biol. 11, 2460–2466
Xu, N., Chen, C.Y. and Shyu, A.B. (2001) Mol. Cell. Biol. 21, 6960–6971
Dean, J.L.E., Sully, G., Wait, R., Rawlinson, L., Clark, A.R. and Saklatvala, J. (2002)
Biochem. J. 366, 709–719
Fan, X.C. and Steitz, J.A. (1998) EMBO J. 17, 3448–3460
Lai, W.S., Carballo, E., Strum, J.R., Kennington, E.A., Phillips, R.S. and Blackshear, P.J.
(1999) Mol. Cell. Biol. 19, 4311–4323
Carballo, E., Lai, W.S. and Blackshear, P.J. (1998) Science 281, 1001–1005
Mahtani, K.R., Brook, M., Dean, J.L., Sully, G., Saklatvala, J. and Clark, A.R. (2001) Mol.
Cell. Biol. 21, 6461–6469
Xu, N., Chen, C.Y. and Shyu, A.B. (1997) Mol. Cell. Biol. 17, 4611–4621
Chen, C.Y., Gherzi, R., Ong, S.E., Chan, E.L., Raijmakers, R., Pruijn, G.J., Stoecklin, G.,
Moroni, C., Mann, M. and Karin, M. (2001) Cell 107, 451–464
Wang, Z., Jiao, X., Carr-Schmid, A. and Kiledjian, M. (2002) Proc. Natl. Acad. Sci. U.S.A.
Van Dijk, E., Cougot, N., Meyer, S., Babajko, S., Wahle, E. and Seraphin, B. (2002)
EMBO J. 21, 6915–6924
Gao, M., Wilusz, C.J., Peltz, S.W. and Wilusz, J. (2001) EMBO J. 20, 1134–1143
Brenner, D.A., O’Hara, M., Angel, P., Chojkier, M. and Karin, M. (1989) Nature (London)
Vincenti, M.P., Coon, C.I., Lee, O. and Brinckerhoff, C.E. (1994) Nucleic Acids Res. 22,
Ridley, S.H., Sarsfield, S.J., Lee, J.C., Bigg, H.F., Cawston, T.E., Taylor, D.J., DeWitt, D.L.
and Saklatvala, J. (1997) J. Immunol. 158, 3165–3173
Reunanen, N., Li, S.P., Ahonen, M., Foschi, M., Han, J. and Kahari, V.M. (2002) J. Biol.
Chem. 277, 32360–32368
Kuno, K., Kanada, N., Nakashima, E., Fujiki, F., Ichimura, F. and Matsushima, K. (1997) J.
Biol. Chem. 272, 556–562
Control of inflammatory response gene expression105
© 2003 Biochemical Society
40.Tortorella, M.D., Burn, T.C., Pratta, M.A., Abbaszade, I., Hollis, J.M., Liu, R., Rosenfeld, Download full-text
S.A., Copeland, R.A., Decicco, C.P., Wynn, R. et al. (1999) Science 284, 1664–1666
Curtis, C.L., Hughes, C.E., Flannery, C.R., Little, C.B., Harwood, J.L. and Caterson, B.
(2000) J. Biol. Chem. 275, 721–724
Newton, R. (2000) Thorax 55, 603–613
Karin, M. (1998) Cell 93, 487–490
Lasa, M., Brook, M., Saklatvala, J. and Clark, A. (2001) Mol. Cell. Biol. 21, 771–780
Lasa, M., Abraham, S.M., Saklatvala, J. and Clark, A.R. (2002) Mol. Cell. Biol. 22,
Franklin, C.C. and Kraft, A.S. (1997) J. Biol. Chem. 272, 16917–16923
Chen, P., Li, J., Barnes, J., Kokkonen, G.C., Lee, J.C. and Liu, Y. (2002) J. Immunol. 169,
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