The novel long PDE4A10 cyclic AMP phosphodiesterase shows a pattern of expression within brain that...
-
Upload
ian-mcphee -
Category
Documents
-
view
213 -
download
0
Transcript of The novel long PDE4A10 cyclic AMP phosphodiesterase shows a pattern of expression within brain that...
The novel long PDE4A10 cyclic AMP phosphodiesterase shows a pattern
of expression within brain that is distinct from the long PDE4A5 and short
PDE4A1 isoforms
Ian McPheea,1, Susan Cochrana,b, Miles D. Houslaya,*aMolecular Pharmacology Group, Division of Biochemistry and Molecular Biology, University of Glasgow, Wolfson Building, IBLS,
Glasgow G12 8QQ, Scotland, UKbYoshitomi Research Institute for Neuroscience, University of Glasgow, West Medical Building, IBLS, Glasgow G12 8QQ, Scotland, UK
Received 2 April 2001; accepted 4 July 2001
Abstract
In situ hybridisation methods were used to map the distribution of the novel long PDE4A10 isoform in the brain. PDE4A10 distribution
was compared to that of the long PDE4A5 isoform and the short PDE4A1 isoform using probes specific for unique sequences within each
of these isoforms. Coronal sections of the brain, taken at the level of the olfactory bulb, prefrontal cortex, striatum, thalamus, hippocampus
and cerebellum, were analysed. Strongest expression of PDE4A isoforms was found in the olfactory bulb granular layer with high signals
also in the piriform cortex, the dentate gyrus and the CA1 and CA2 pyramidal cells. For the two long forms, level general staining was
noted throughout the striatum, thalamus and hippocampus but no signal was evident in the cerebellum. The long PDE4A10 and PDE4A5
isoforms localised to essentially the same regions throughout the brain, although PDE4A10 was uniquely expressed in the major island of
Calleja. A signal for the short PDE4A1 isoform was found in regions in which the two long isoforms were both expressed, with the
exception of the medial nucleus of the amygdala where weak signals for PDE4A5 and PDE4A10 were detected but PDE4A1 was absent.
Uniquely, strong signals for PDE4A1 were detected in the glomerular layer of the olfactory bulb, the CA3 pyramidal cell region and the
cerebellum; areas where signals for the two long forms were not evident. PDE4A transcripts for both PDE4A5 and PDE4A10 were not
apparent in the brain stem and those for PDE4A1 were low. PDE4A isoforms are present in several key areas of the brain and therefore
present valid targets for therapeutic interventions. Whilst the two long PDE4A isoforms show a remarkably similar distribution, in at least
three regions there is clear segregation between their pattern of expression and that of the PDE4A1 short form. This identifies differential
regulation of the expression of PDE4A long and short isoforms. We suggest that specific PDE4A isoforms may have distinct functional
roles in the brain, indicating that PDE4A isoform-selective inhibitors may have specific therapeutic and pharmacologic properties. D 2001
Elsevier Science Inc. All rights reserved.
Keywords: Cyclic AMP; Phosphodiesterase; PDE4; Brain; Rolipram; CA1; CA2; CA3; Learning; Memory; Depression
1. Introduction
Cyclic AMP (cAMP) has been implicated in the regu-
lation of brain activity in a number of areas such as synaptic
plasticity, learning and memory, emesis and depression.
Until very recently cAMP was thought to exert its effects
solely through the activation of protein kinase A (PKA) and
in so doing modulate signal transduction cascades and
transcription. However, new cAMP effector proteins have
been discovered which, like PKA, bind to and are directly
activated by cAMP. These include cAMP-gated ion channels
[1–3] and GEFs [4–6]. These range of effector molecules
have been implicated in the regulation of neurones [7,8].
cAMP phosphodiesterases provide the sole means
whereby cAMP can be degraded in cells. As such these
enzymes are poised to exert a major regulatory role on
cAMP signalling. A large multigene family expresses a
myriad of enzymes able to hydrolyse cAMP. However,
recently there has been considerable interest in isoforms of
0898-6568/01/$ – see front matter D 2001 Elsevier Science Inc. All rights reserved.
PII: S0898 -6568 (01 )00217 -0
* Corresponding author. Tel.: +44-141-330-5903; fax: +44-141-330-
4365/462.
E-mail address: [email protected] (M.D. Houslay).1 Current address: Scottish Biomedical, Block H, Ground Floor,
Telford Pavilion, Todd Campus West of Scotland Science Park, Glasgow
G20 0XA, Scotland, UK.
Cellular Signalling 13 (2001) 911–918
the multigene PDE4 cAMP-specific phosphodiesterase fam-
ily. This arose originally from the observations that inactiv-
ating mutations in the cognate enzyme in Drosophila
melanogaster caused learning and memory difficulties [9–
12]. More pertinently, however, the archetypal PDE4 select-
ive inhibitor rolipram has been shown to be neuroactive and
to have antidepressant properties shown in both animal
models and in clinical trials [13–16].
There are four PDE4 subfamilies, encoded by separate
genes (A, B, C, D) [17–19]. These share three regions of
homology, namely the catalytic unit and two upstream
conserved regions, called UCR1 and UCR2. Each of these
subfamilies, however, generates distinct isoforms that are
characterised by unique N-terminal regions. The suggested
role [17] of these N-terminal regions appears to be associated
with defining the intracellular localisation of the specific
isoform as well as exerting a regulatory effect on its catalytic
activity and sensitivity to inhibition. Such isoforms, how-
ever, fall into two classes, namely long forms that exhibit
both UCR1 and UCR2 and short forms that lack UCR1. This
confers functionally distinct properties on these two classes
of isoforms. Thus, for example, UCR1 interacts with UCR2
to provide a module [20] that allows for the activation of
long isoforms upon the phosphorylation of UCR1 by PKA
[21,22], thus providing a cellular desensitisation system
[19,23]. Additionally, the paired UCR1/UCR2 module
directs ERK phosphorylation of the PDE4 catalytic unit to
confer inhibition on long isoforms, whilst the lone UCR2 in
short forms programmes resultant inhibition [24].
Recently we have cloned [25] a novel PDE4A long
isoform, called PDE4A10. This is one of a number of
PDE4A long isoforms [17]. Thus three catalytically active
long PDE4A isoforms have been identified in rat; namely
PDE4A5 [26,27], PDE4A8 [28] and PDE4A10 [25]. In
addition to this the short isoform, PDE4A1 has also been
identified [29] and characterised [30,31]. Except for
PDE4A8, all of these isoforms have been shown to have
homologues in man and mouse [17]. Such PDE4A isoforms
differ in relative catalytic activity, sensitivity to inhibition
by rolipram and thermostability [17,25]. In addition, all
these isoforms differ markedly in their intracellular local-
isation [25,31–33] and only the PDE4A5 isoform appears
to become activated through stimulation of the PI-3 kinase
cascade [34]. Interestingly, the PDE4A5 isoform appears to
have a role in the survival of at least certain cells and is the
sole PDE4 isoform that is cleaved by caspase-3 during
apoptosis, causing it to redistribute within the cell [32].
These differences suggest that the various PDE4A isoforms
may have specific functional roles in the cells where they
are expressed.
In situ hybridisation studies have been done previously
using ‘pan’ PDE4A probes in order to gain insight into the
overall pattern of expression of the various PDE4 classes
[35–37]. However, such analyses will be biased by the
level of expression of the predominant isoforms within a
particular PDE4 subclass. No attempt has been made to
compare the expression pattern in brain of isoforms within a
particular PDE4 subfamily. As PDE4A isoforms have been
extensively studied and shown to have properties that
uniquely characterise them [17], we have set out here to
compare the distribution of the novel long PDE4A10 iso-
form with the well-established long PDE4A5 and short
PDE4A1 isoforms. We did not attempt to analyse the
testis-specific PDE4A8 isoform, as it is not expressed in
brain [28]. We show that whilst there is overlap in the
expression profile of these various PDE4A isoforms, espe-
cially of the two long isoforms, there are various regions in
the brain where particular isoforms of the PDE4A subfam-
ily are uniquely expressed.
2. Materials and methods
2.1. Animals
Male Wistar rats (300 g, purchased from Harlen-Olac,
UK) were housed under a 12-h light/dark cycle in a
temperature and humidity controlled environment with free
access to food and water. Animals were killed by cervical
dislocation. The brains were rapidly removed and frozen in
isopentane cooled to � 42�C on solid CO2 and then coated
in embedding medium (Lipshaws) and stored at � 70�Cuntil required.
2.2. Probes and labelling
All probes were 45-mer oligonucleotides purchased from
Interacteva. The probe sequences used were as follows:
PDE4A5 Genbank accession number L27057, probe
4A5AS of sequence cgc tct atg ggc cgg tgc ggt gag cgc tct
gtc tct gag cgc tcg; PDE4A10 Genbank accession number
AF110461, probe 4A10AS of sequence gtc ctc ctc gct gaa
gga gaa atg ggt cag tga ctc tgg tcc tag; PDE4A1 Genbank
accession number M26715, probe 4A1AS of sequence cag
cca ggg ctt gga gca ggt ctc gca gaa gaa gtc aac cag agg.
The probes were 30 end-labelled with terminal deoxyri-
bonucleotidyl transferase (Pharmacia) and with the isotope
5-a-35S-dATP (NEN, specific activity > 1000 Ci/mmol) and
incubated at 37�C for 1 h. The reaction was terminated by
addition of 60 ml diethyl pyrocarbonate (DEPC)-treated
water. The probe was purified using QIAquick Nucleotide
Removal kit (Qiagen). The extent of probe labelling was
assessed using b-scintillation counting, and probes labelled
from 100,000 to 300,000 dpm ml� 1 were used for in situ
hybridisation. One microliter 1 M dithiothreitol (DTT) was
added to the labelled probe in order to prevent oxidation.
Labelled probes were stored at � 20�C until required.
2.3. Dot blot
Probes used in the dot blot were 50 end labelled with T4
polynucleotide kinase (Promega) and g-32P-ATP (Amer-
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918912
sham, specific activity >3000 Ci/mmol). The reaction
proceeded at 37�C for 15 min and was terminated by
adding EDTA to a final concentration of 20 mM. The
probe was purified using QIAquick Nucleotide Removal
kit (Qiagen). Plasmid DNA (approximately 10 ng), con-
taining the genes of interest, were spotted onto hybond –N
membrane, allowed to dry and cross-linked using a trans-
illuminator for 1 min. The membrane was then prehybri-
dised in a solution containing 7% (w/v) SDS, 0.5 M
phosphate, pH 7.2 for 1 h at 65�C in a rotating oven
before freshly boiled radiolabelled probe (10 pmol) was
added. Hybridisation was allowed to proceed overnight
before the probe was poured off and the membrane washed
in SSC buffer. The initial wash was carried out in 3� SSC
for 5 min before washing in 1� SSC, for 30 min each
time, until the background activity was removed from the
membrane. The activity on the filters was imaged using
phosphoimager (Fuji).
2.4. Section collection and preparation
Twenty-micrometer sections were cut on a cryostat at
� 20�C (Leica CM1850) collected onto poly-L-lysine coated
slides from the following bregma level: 6.70 mm (olfactory
bulb), 3.20 mm (prefrontal cortex), 0.20 mm (striatum),
� 2.80 mm (midline thalamus), � 4.80 mm (hippocampus)
and � 10.52 mm (cerebellum). Sections were dried at room
temperature then fixed in freshly prepared 4% (wt/vol)
paraformaldehyde in phosphate-buffered saline (PBS) for
5 min. After rinsing the sections were sequentially dehy-
drated in 70%, 95% and 100% ethanol before being stored
under ethanol at 4�C.
2.5. In situ hybridisation
Sections were hybridised overnight at 42�C in a hybrid-
isation mixture comprising hybridisation buffer (50%
deionised formamide, 20% 20� standard saline citrate
[20� SSC = 3 M sodium chloride; 0.3 M sodium citrate,
pH 7], 5% 0.5 M sodium phosphate [pH 7], 1% 0.1 M
sodium pyrophosphate, 2% 5 mg ml� 1 polyadenylic acid,
10% dextran sulphate, volume adjusted to 50 ml with
DEPC-treated water), 5 ng 5000 ml � 1 labelled probe and
1 M DTT in the proportions 100:1:4. Two hundred micro-
liters of hybridisation mixture was applied to each slide
and the sections were then covered with parafilm. After
overnight hybridisation under humidified conditions, the
parafilm was removed from each slide under 1� SSC,
then washed for 30 min in 1� SSC warmed to 60�C. Thesections were then washed in 1� SSC then 0.1� SSC at
room temperature and dehydrated in 70% then 95%
ethanol. Once dry, the sections were exposed to auto-
radiographic film (Biomax MR, Kodak) for 14 days.
Images were obtained via the MCID image analysis system
(M5, Canada).
3. Results and discussion
3.1. Fidelity of the probes
In man it has been shown that the extreme 50 exon that
characterises each of the three isoforms studied here is
unique [25,38]. Thus transcripts from the three PDE4A
isoforms analysed here will each have a distinct 50 region
whose sequence is highly conserved between different
species [17,25]. We have exploited the differences in
sequence of the 50 regions of the PDE4A1, PDE4A5 and
PDE4A10 isoforms to design end-labelled probes that were
specific for each of these isoforms and which could then
be used in the in situ hybridisation experiments to deter-
mine individual expression profiles. We set out to confirm
the specificity of each of these probes. To do this, ‘dot
blots’ were prepared in which plasmid DNA containing the
three different PDE4A isoforms was spotted onto nylon
membranes and then probed with each of the end-labelled
probes (Fig. 1). In each case the end-labelled probes
identified exclusively the appropriate PDE4A isoform they
were designed to interact with. Thus we can expect that
the in situ probes will bind specifically to the appropriate
mRNA targets.
3.2. In situ hybridisation
In these analyses we were able to show that appropriate
sense control probes did not bind to the tissue sections and
the signal obtained for each (antisense) probe could be
competed out with a 10-fold excess of unlabelled probe.
3.3. Olfactory bulb
Transcripts for all three of these PDE4A isoforms
appeared to be expressed to a high degree in the olfactory
bulb (Fig. 2), with transcripts for PDE4A1, PDE4A5 and
PDE4A10 being present in large amounts in the mitral and
granular cell layer. Intriguingly, however, whilst a clear
signal was displayed for PDE4A1 transcripts in the glom-
Fig. 1. Specificity of the in situ probes. Plasmid DNA from PDE4A1,
PDE4A5 and PDE4A10 rat isoforms was spotted onto nylon membranes
and then probed with the rat PDE4A isoform-specific oligonucleotide
sequences used for the in situ studies. Data are typical of experiments done
at least three times.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918 913
erular layer, only weak signals were seen for PDE4A5 and
PDE4A10. It is interesting to compare these data with the
immunohistochemical study of Cherry and Davis [37] done
on mouse brain. They used an antiserum that, whilst
specific for the PDE4A subclass, was unable to discriminate
between the various isoforms i.e., it was a ‘pan’ PDE4A
antiserum. Using this antiserum they observed a clear signal
for PDE4A protein in the glomerular layer only. This may
reflect a difference between rat and mouse. However,
another possibility is that transcripts present in glomerular
and granular layers are not translated to the same degree. If,
however, PDE4A5 and PDE4A10 transcripts were not
being translated efficiently, then one might have expected
to observe a large excess of PDE4A1 in Western blot
analyses. However, Western blot studies done on both rat
[27] and mouse [37] indicated that bands corresponding to
the similarly sized PDE4A10/PDE4A5 were present at
similar levels to that of PDE4A1 in homogenates of the
olfactory bulb. Of course it may be that the in situ hybrid-
isation method may exhibit a higher degree of sensitivity
than immunohistochemical analyses. Alternatively, the
mRNA detected by the in situ method may be located in
the cell bodies of neurones of the granular layer with the
expressed PDE4A protein translocated along the length of
the axon to the glomerular layer. This might allow the
PDE4A species to be functionally active at the synapses in
this region.
It is clear from these analyses that PDE4A isoforms are
highly expressed in areas that are important to odorant
signal transduction, indicating that they are likely to be
involved in the tuning, processing and possible detection of
odorant signals. PDE4A isoforms in the olfactory bulb may
even have a wider influence on brain function, since the
regions where they are detected have been implicated in
feeding responses to amino acid deficiencies and memory
and where the phosphorylation of cAMP response element
binding protein (CREB) appears to play a role [39–42]. In
addition, abnormalities in these areas are also associated
Fig. 3. Prefrontal cortex sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The
areas highlighted are: prelimbic region (PL); primary motor cortex (PMC); and piriform cortex (PC). Data are typical of experiments done at least three times.
Fig. 2. Olfactory bulb sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The areas
shown are: external plexiform layer (ExP); glomerular layer (GL); granular layer (GR); and olfactory ventricle (OV). Data are typical of experiments done at
least three times.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918914
with limbic kindling and seizures such as those seen in
epilepsy [43–45].
3.4. Prefrontal cortex and striatum
Signals for mRNA transcripts of all three of these
PDE4A isoforms were seen in the piriform cortex, the
prefrontal cortex (Fig. 3) and striatum sections (Fig. 4).
These structures have been implicated as being involved in a
number of processes, such as olfactory signal processing,
memory, depression and seizures [43,45–47]. However, the
signal for each of these isoforms was more diffuse in the
primary motor cortex prelimbic region of the prefrontal
cortex, the anterior cingulate cortex and somatosensory
cortex of the striatum (Figs. 3 and 4). The deep layers of
the somatosensory cortex showed a relatively stronger
signal than the superficial layers. PDE4A1 appeared to be
uniformly distributed through the anterior cingulated cortex
and somatosensory cortex, whilst levels of PDE4A5 and
PDE4A10 appeared to be relatively higher in the anterior
cingulated cortex (Fig. 4). Interestingly, however, PDE4A10
uniquely showed a strong and well-defined signal in the
major island of Calleja (Fig. 4), a region of the brain that has
been implicated in depression [48]. This was the clearest
indication that we observed in this study of a difference
in the expression patterns of the PDE4A10 and PDE4A5
long isoforms.
3.5. Hippocampus and hypothalamus
Strong, clear signals for transcripts of all three PDE4A
isoforms were seen in the dentate gyrus, the CA1 and CA2
regions of the hippocampus (Figs. 5 and 6). However, we
noted that PDE4A1 uniquely provided a strong signal in the
CA3 region (Figs. 5 and 6). Stronger expression of PDE4A1
was also seen in the thalamus (Fig. 5), the superficial layer
Fig. 4. Striatum sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The areas shown
are: anterior cingulate cortex (AC); somatosensory cortex (SC); striatum (St); major island of Calleja (MC); olfactory tubercle (OT); and piriform cortex (PC).
Data are typical of experiments done at least three times.
Fig. 5. Thalamus sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The areas
shown are: the CA1, CA2 and CA3 areas of the pyramidal cell layer; the dentate gyrus (DG); and medial nucleus of the amygdala (MN). Data are typical of
experiments done at least three times.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918 915
of the retrosplenial cortex and the lateral and medial layer of
the mammillary body (Fig. 6). The CA1 and dentate gyrus
regions are very important for cognitive function, such as
memory, with modulation of cAMP in these regions affect-
ing long-term potentiation [9,12,29,49] and altering the
activity of presynaptic neurones [50]. In addition to this,
expression of the CREB in the hippocampus produces an
antidepressant effect [51]. Thus, PDE4A isoforms may have
particular importance in regulating plasticity processes
associated with these brain areas. Consistent with this, the
PDE4 selective inhibitor rolipram has been shown to facil-
itate long-term potentiation and enhance memory [52–54].
In this regard it also has been shown to induce the
expression of BNDF in the CA1, CA3 and the dentate
gyrus [55], a process associated with antidepression. It is
thus very intriguing to see such profound differences in the
distribution of these various PDE4A isoforms. This may
signify particular PDE4A isoforms as providing appropriate
targets for the development of cognitive enhancers and also
antidepressive therapeutics.
The medial nucleus of the amygdala provided an area of
the brain where both PDE4A5 and PDE4A10 were clearly
expressed (Fig. 5). This region is typically associated with
emotional responses, learning and social awareness and has
been implicated in depression and autism [56–59].
3.6. Cerebellum and paraflocculus
Little or no expression of either PDE4A10 or PDE4A5
was evident in the cerebellum. In profound contrast to this,
however, PDE4A1 appeared to be strongly expressed in
both the cerebellum, where it was exclusively localised to
the grey matter, and also in the paraflocculus (Fig. 7).
Indeed, the signal achieved by PDE4A1 was at a compar-
ably high level to that seen for PDE4A1 in the olfactory
bulb regions. This is consistent with Western blotting
Fig. 6. Hippocampus sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The areas
shown are: the CA1, CA2 and CA3 areas of the pyramidal cell layer; the dentate gyrus (DG); mammillary body medial nuclei (MN); mammillary body lateral
nuclei (LN); auditory cortex (AC); visual cortex (VC); and retrosplenial cortex (RC). Data are typical of experiments done at least three times.
Fig. 7. Cerebral sections probed with PDE4 isoform-specific probes. The probes used were for PDE4A1 (A), PDE4A5 (B) and PDE4A10 (C). The areas shown
are: grey matter (GM); white matter (WM); and paraflocculus (Pf). Data are typical of experiments done at least three times.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918916
studies done on rat cerebellum fractions, which only iden-
tified a single PDE4A immunoreactive species of the size of
PDE4A1 [27]. This may indicate a specific role for the
PDE4A1 isoform in some of the functions associated with
these structures such as motor control, temporal sensing and
occular signal processing.
In the brain stem, expression of PDE4A1 appeared to be
low and diffuse whilst transcripts for PDE4A5 and
PDE4A10 were not evident. This corroborates Western
blotting studies done on membrane and cytosol extracts
from rat brain stem that identified a single immunoreactive
species of the size of PDE4A1 in brain stem [27].
4. Conclusion
We have designed probes that can be used to detect
specifically transcripts for the three major PDE4A isoforms
expressed in brain. Their use has allowed us to show that
these isoforms from the PDE4A gene are differentially
expressed in various brain areas. Studies using inhibitors
that are selective for PDE4 cAMP-specific phosphodies-
terases have led to the suggestion that PDE4 enzymes have a
major role in the regulation of learning, memory and the
psychological state of an individual. Here we have shown
that PDE4A isoforms are present in areas of the brain
closely associated these processes such as the piriform
cortex, amygdala and hippocampus.
Expression of the two long PDE4A isoforms was highest
in the olfactory bulb and for the short PDE4A1 isoform
highest in the olfactory bulb, the cerebellum and the
paraflocculus. It is interesting to note that the two long
isoforms PDE4A5 and PDE4A10 displayed very similar
distribution throughout the brain except in the major island
of Calleja where only PDE4A10 was seen. This suggests
that the promoter regions controlling expression of these
two long isoforms are likely to be rather similar. Notwith-
standing the fact that PDE4A5 and the recently discovered
PDE4A10 are similar in size, they appear to differ in a
number of properties [25], implying that they may have
distinct functional roles in cells where they are both
expressed together.
With the exception of the major island of Calleja, where
PDE4A10 was uniquely expressed (Fig. 4), the short
PDE4A1 isoform was present in every area where the
PDE4A5 and PDE4A10 long isoforms were expressed.
However, PDE4A1 was uniquely found in several areas
where PDE4A5 and PDE4A10 were absent, such as the
cerebellum (Fig. 7), the CA3 region of the hippocampus
(Figs. 5 and 6), and the glomerular layer of the olfactory
bulb (Fig. 2). PDE4A1 differs markedly from the long
PDE4A forms. For example, it lacks UCR1 [17,38] and
so is insensitive to stimulatory phosphorylation by PKA. It
is also the only PDE4 isoform that is entirely membrane-
associated [31] and this is attributable to its unique 25 amino
acid N-terminal region [31,60,61]. These distinct attributes
may be pivotal to the particular functioning of PDE4A1 in
cells and serve to distinguish it dramatically from the
PDE4A5 and PDE4A10 long forms.
Our studies suggest that subfamily- and even isoform-
selective PDE4 inhibitors may have distinct pharmacological
properties and particular therapeutic usage. Also that disrup-
tion of the exons encoding the unique N-terminal regions of
these PDE4A isoforms may generate distinct phenotypes.
Acknowledgments
We thank the Medical Research Council (UK) for
financial support and Professor Brian Morris (YRING,
IBLS, University of Glasgow, Glasgow, UK) for helpful
discussion.
References
[1] Finn JT, Grunwald ME, Yau KW. Annu Rev Physiol 1996;58:
395–426.
[2] Kaupp UB. Curr Opin Neurobiol 1995;5(4):434–42.
[3] Zagotta WN, Siegelbaum SA. Annu Rev Neurosci 1996;19:235–63.
[4] de Rooij J, Zwartkruis FJ, Verheijen MH, Cool RH, Nijman SM,
Wittinghofer A, Bos JL. Nature 1998;396(6710):474–7.
[5] Kawasaki H, Springett GM, Mochizuki N, Toki M, Nakaya M,
Matsuda M, Housman DE, Graybiel AM. Science 1998;282
(5397):2275–9.
[6] Kawasaki H, Springett GM, Toki S, Canales JJ, Harlan P, Blumenstiel
JP, Chen EJ, Bany IA, Mochizuki N, Ashbacher A, Matsuda M, Hous-
man DE, Graybiel AM. Proc Natl Acad Sci USA 1998;95(22):
13278–83.
[7] He Q, Wu G, Lapointe MC. Am J Physiol: Endocrinol Metab
2000;278(6):E1115–23.
[8] Strijbos PJ, Pratt GD, Khan S, Charles IG, Garthwaite J. Eur J Neuro-
sci 1999;11(12):4463–7.
[9] Davis RL. Physiol Rev 1996;76:299–317.
[10] Qiu Y, Chen CN, Malone T, Richter L, Beckendorf SK, Davis RL.
J Mol Biol 1991;222(3):553–65.
[11] Qiu Y, Davis RL. Genes Dev 1993;7(7 B):1447–58.
[12] Davis RL, Cherry J, Dauwalder B, Han PL, Skoulakis E. Mol Cell
Biochem 1995;149–150:271–8.
[13] Wachtel H. Psychopharmacology 1982;77:309–14.
[14] Wachtel H. Neuropharmacology 1983;22:267–72.
[15] O’Donnell JM. J Pharmacol Exp Ther 1993;264(3):1168–78.
[16] O’Donnell JM, Frith S. Pharmacol, Biochem Behav 1999;63(1):
185–92.
[17] Houslay MD, Sullivan M, Bolger GB. Adv Pharmacol 1998;44:
225–342.
[18] Bolger G. Cell Signalling 1994;6:851–9.
[19] Conti M, Jin SLC. Prog Nucleic Acid Res 1999;63:1–38.
[20] Beard MB, Olsen AE, Jones RE, Erdogan S, Houslay MD, Bolger
GB. J Biol Chem 2000;275(14):10349–58.
[21] Sette C, Conti M. J Biol Chem 1996;271(28):16526–34.
[22] Sette C, Iona S, Conti M. J Biol Chem 1994;269(12):9245–52.
[23] Oki N, Takahashi SI, Hidaka H, Conti M. J Biol Chem 2000;275(15):
10831–7.
[24] MacKenzie SJ, Baillie GS, McPhee I, Bolger GB, Houslay MD. J Biol
Chem 2000;275:16609–17.
[25] Rena G, Begg F, Ross A, MacKenzie C, McPhee I, Campbell L,
Huston E, Sullivan M, Houslay MD. Mol Pharmacol 2001;59:
996–1011.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918 917
[26] Bolger GB, Rodgers L, Riggs M. Gene 1994;149(2):237–44.
[27] McPhee I, Pooley L, Lobban M, Bolger G, Houslay MD. Biochem J
1995;310(3):965–74.
[28] Bolger GB, McPhee I, Houslay MD. J Biol Chem 1996;271(2):
1065–71.
[29] Davis RL, Takayasu H, Eberwine M, Myres J. Proc Natl Acad Sci
USA 1989;86:3604–8.
[30] Shakur Y, Pryde JG, Houslay MD. Biochem J 1993;292(3):677–86.
[31] Shakur Y, Wilson M, Pooley L, Lobban M, Griffiths SL, Campbell
AM, Beattie J, Daly C, Houslay MD. Biochem J 1995;306(3):801–9.
[32] Huston E, Beard M, McCallum F, Pyne NJ, Vandenabeele P, Scotland
G, Houslay MD. J Biol Chem 2000;275(36):28063–74.
[33] Pooley L, Shakur Y, Rena G, Houslay MD. Biochem J 1997;271:
177–85.
[34] MacKenzie S, Fleming I, Houslay MD, Anderson NG, Kilgour E.
Biochem J 1997;324:159–65.
[35] Engels P, AbdelAl S, Hulley P, Lubbert H. J Neurosci Res 1995;41:
169–78.
[36] Cherry JA, Davis RL. J Neurobiol 1995;28(1):102–13.
[37] Cherry JA, Davis RL. J Comp Neurol 1999;407(2):287–301.
[38] Sullivan M, Rena G, Begg F, Gordon L, Olsen AS, Houslay MD.
Biochem J 1998;333(Pt 3):693–703.
[39] Wilson DA. J Neurophysiol 2000;84(6):3036–42.
[40] Gheusi G, Cremer H, McLean H, Chazal G, Vincent JD, Lledo PM.
Proc Natl Acad Sci USA 2000;97(4):1823–8.
[41] Coronas V, Krantic S, Jourdan F, Moyse E. Neuroscience 1999;90(1):
69–78.
[42] Yuan Q, Harley CW, Bruce JC, Darby-King A, McLean JH. Learn
Mem 2000;7(6):413–21.
[43] Loscher W, Ebert U. Prog Neurobiol 1996;50(5–6):427–81.
[44] Woldbye DP, Bolwig TG, Kragh J, Jorgensen OS. Neurochem Res
1996;21(5):585–93.
[45] Ferland RJ, Applegate CD. Epilepsy Res 1998;30(1):49–62.
[46] Barkai E, Hasselmo MH. Mol Neurobiol 1997;15(1):17–29.
[47] Litaudon P, Mouly AM, Sullivan R, Gervais R, Cattarelli M. Eur J
Neurosci 1997;9(8):1593–602.
[48] Maj J, Dziedzicka-Wasylewska M, Rogoz R, Rogoz Z. Eur J Pharma-
col 1998;351(1):31–7.
[49] Schulz S, Siemer H, Krug M, Hollt V. J Neurosci 1999;19(13):
5683–92.
[50] Ma L, Zablow L, Kandel ER, Siegelbaum SA. Nat Neurosci 1999;
2(1):24–30.
[51] Chen AC, Shirayama Y, Shin K, Neve RL, Duman RS. Biol Psychia-
try 2001;49(9):753–62.
[52] Barad M, Bourtchouladze R, Winder DG, Golan H, Kandel E. Proc
Natl Acad Sci USA 1998;95(25):15020–5.
[53] Zhang HT, Crissman AM, Dorairaj NR, Chandler LJ, O’Donnell JM.
Neuropsychopharmacology 2000;23(2):198–204.
[54] Zhang HT, O’Donnell JM. Psychopharmacology (Berlin) 2000;
150(3):311–6.
[55] Fujimaki K, Morinobu S, Duman RS. Neuropsychopharmacology
2000;22(1):42–51.
[56] Drevets WC. Ann NY Acad Sci 1999;877:614–37.
[57] McKenna KE. Int J Impotence Res 1998;10(Suppl 1):S25–34.
[58] Newman SW. Ann NY Acad Sci 1999;877:242–57.
[59] Bachevalier J, Beauregard M, Alvarado MC. Behav Neurosci 1999;
113(6):1127–51.
[60] Scotland G, Houslay MD. Biochem J 1995;308(2):673–81.
[61] Smith KJ, Scotland G, Beattie J, Trayer IP, Houslay MD. J Biol Chem
1996;271:16703–11.
I. McPhee et al. / Cellular Signalling 13 (2001) 911–918918