BIOCHEMICAL
Vol. 189, No. 3, 1992 December
AND BIOPHYSICAL
RESEARCH COMMUNICATIONS Pages
30, 1992
1553-l
560
IUENTIFICATION OF NGF-RESPONSE ELIN TBE RAT NEUROPEPTIUEY GENEANUINUUCTIONOFTBEBINUINGPROTEINS Hiroshi
Higuchi,’ Koichi
Nakano and Naomasa Miki
Department of Pharmacology I, Osaka University Medical School, 2-2 Yamadaoka, Suita, Osaka 565, Japan Received
November
24,
1992
Y (NPY) increases by 100 SUMMARY Gene expression of the rat neuropeptide into sympathetic neuron-like cells times, as the PC12 cells differentiate with NGF treatment and this increase is partly due to transcriptional activation of the NPY gene (Sabol and Higuchi, Mol. Endocrinol. 4, 384, 1990). To identify the NGF-response element, a transient expression assay was carried out by using the CAT reporter genes containing various lengths of The 48-base the 5’ upstream region of the NPY gene in the PC12 cells. element (-80/-33 upstream of the Cap site) was identified as a NGF-response the existence of at least two element (NGFRE). Gel shift assay indicated The binding activity of the protein(s) DNA-binding proteins to NGFRE. (NDFl) to the upper region (-SO/-63) was increased by J-fold with NGF treatment for 24 h. These findings suggest that these nuclear proteins are involved in the enhanced transcription of the NPY gene by NGF. o 1992?,cademl. PTPSL,Inc.
The rat studying ment
PC12 pheochromocytoma
the molecular
with
basis
GTP) is produced tion
of
protein),
of nerve
NGF differentiates
cells through high affinity horylation of Trk A itself both
within
the
tional
factors of
growth
provides factor into
a useful
model for Treat(NGF) actions.
sympathetic
neuron-like
NGF receptor (Trk A), following tyrosine phospwithin 5 min (1). The active form of Ras (Ras-
20 min after
NGF treatment stimulator)
as the result
of activa-
and GAP (GTPase activating
the
various serine/threonine kinases are actiIt has been suggested that the various active Ras (2,3). are transcriptional factors, genes, which are generally
induced by the activation of these late genes such as neuron-specific induction
line
PC12 cells
GDS (GDP-dissociation
and subsequently
vated by the immediate-early
cell
slowly late
protein kinases in 2 h (4,5). Then the genes are induced by these transcrip-
and persistently
genes
results
over
in the
several
differentiation
hours
or days, and the of
PC12 cells
into
1To whom correspondence should be addressed. 0006-291X/92
1553
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Copvight 0 1992 by Academic Press, Inc. Ali rights of reproduction in any form reserwd.
Vol.
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BIOCHEMICAL
3, 1992
sympathetic
neuron-like
However,
cells.
nism of how the neuron-specific Neuropeptide
into
The data To NGF (6).
responsiveness
that
activation
synthesis. by
little
at
that the
is known
of
neuron-like
about
in the cells
is partly
NPY gene, which
level,
mecha-
neurons
by NGF. (by 8 fold)
requires
we analysed
region of the NPY gene by chloramphenicol acetyltransferase and identified the DNA-binding factors to NGFRE.
(6-11).
PC12 cells, Nuclear due to
ongoing
the NPY gene is one of late cis-element (NGFRE) which
transcriptional
the
by NGF.
sympathetic
by loo-fold
increase
of the
indicate identify the
this
RESEARCH COMMUNICATIONS
genes are induced
is increased
the sympathetic
on assay demonstrated transcriptional
late
Y (NPY) is a cotransmitter
The NPY gene expression differentiated
AND BIOPHYSICAL
the
when runthe
protein
genes induced confers NGF5’ upstream (CAT) assay
MATERIALSANDMETEODS Materials. NGF was obtained from Sigma. [a- 32P]dCTP and [14Clchloramphenicol were Restriction and modifying enzymes were from purchased from Amersham. Toyobo and Takara. Cell culture. Rat PC12 pheochromocytoma cells, obtained fro ATCC (American Type Culture Collection) were cultured at 37°C in 75 cm 9 flasks in 85% DMEM, 10% heat-inactivated horse serum, and 5% heat-inactivated fetal calf serum with an atmosphere of 90% air-lot carbon dioxide. Medium was changed every day (6). Plasmid construction. The source of rat NPY genomic DNA was a plasmid subclone (pRNPYKB1) containing 3.5kb KpnI-BglII fragment covering the 5’-upstream region, first exon, and first intron of rat NPY gene (12). The upstream region (3.5 kb KpnI-BglII fragment) was inserted into the promoterless pUCATSV1 CAT reporter plasmid (12). Deletion mutants containing various lengths of 5’-flanking region of the rat NPY gene were obtained by digestion of the longest pUCATNPY plasmid with appropriate restriction enzymes or by PCR. DNA sequencing. Inserted portions of pUCATNPY plasmids were confirmed with the pUC sequencing kit (Boeringer) by double stranded sequencing. DNA transfection. CaP04-DNA precipitates (10-25~ g of test plasmid per plate) were prepared as described (12). After incubation for 6 h with CaP04-DNA precipitates, cells were shocked for 2 min with 15% glycerol in HBS buffer. The transfected cells were incubated with NGF for 48 h and harvested for the measurement of CAT activity. Most experiments included a positive control transfection with pRSVCAT DNA. CAT assay. CAT assays were carried out as previously described (12). Protein (500 fig) from cell extract was incubated at 37°C for 30 min in 180~ 1 of the reaction mixture containing 0.2 M Tris-HCl (PH 7.5), 80 mM acetyl CoA, 3.7 kBq [14Clchloramphenicol. Acetylated and nonacetylated forms of [14C] chloramphenicol were separated on thin layer plate (Whatman LKGDF) and quantitated by scanning the plate with a Fujix Bioimage Analyzer (BAS2000). Gel retardation assay. Nuclear extracts from the PC12 cells were prepared according to the method of Dignam et al (13). Protein assay was carried out by Bradford’s method (14). The two double-stranded oligonucleotides (NGFUds (-80/-51) and NGFDds (-62/-33)), and other oligonucleotides containing the consensus 1554
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AND BIOPHYSICAL
RESEARCH COMMUNICATIONS
sequences (APl, Spl, and zif268) were synthesized. Gel retardation assay was performed on 4% polyacrylamide gel for 2 h at 150 V in a solution containing 6.7 mM Tris-glycine (pH 7.9), 3.3 mM sodium acetate and 1 mM EDTA, as previously described (15) and the bands of DNA-protein complexes were quantitated by a Fujix Bioimage Analyzer (BAS2000).
RESULTS
In coincidence
with
AND
the previous
DISCUSSION
finding
that
undifferentiated
express low amount of NPY mRNA (0.16 pg/p g total PY (-2.9kb/+397b) CAT reporter gene exhibited the ity,
which
activity rat
was estimated
was lower
to
than
preproenkephalin
be 0.3 % of
that
that
RNA; Ref.lG), the pUCATNlow transcriptional activof
control
of a pUCATENKHSBL plasmid
A (ENK A) gene promorter
PC12 cells
pRSVCAT. which
from -1.2kb
This
contains
to
the
+49b
in the
markedly
the
same CAT vector. However,
treatment
transcriptional accordance Ref.6).
with
the
As shown determined various
in
not
Fig.
data
this
lA,
regions
near
the
finally
identified
of
inducing
the
bind
element
Cap site
to
the middle unique
conserved
81% homology), this
region
a small
portion.
28 bp
near
(Fig.
through
high
by
(-80/-33 between
in
1A and 1 x
affinity
that
the
structure
primers Cap site) (Fig.
(Fig.
as a in
factors
2).
This
cis
5’-GAGGCCCCTC-3’) in
(-90/-63;
a part
of the
5’-TGGGAGTCACCC-
ester-
similar
and
1B).
transcriptional
constitutes
in phorbol
the
promoter
(39 nucleotides
(-61/-52;
motifs
the
the
conserved
(-80/-63)
using
with
proper
of
was
enzyme sites.
NGF-inducibility
structure
are
by
genes
upstream
lated
There
NPY gene
Cap site
human and rat
suggesting
region
the
PCR using
5-fold
palindromic
(16).
of
at restriction
are evolutionarily
The upper
the
GGGCGTGACTGCCC-J’),which may participate transcription
8.5-fold,
assay
NPY-CAT reporter
palindromic
imperfect
element
ligation
constructed
a 48 bp-element
contains
by
the NPY-CAT gene was about
(-80/+18)
made by the
we made the
This NGFRE is well which
run-on
is mediated
NGF-response
NGFRE of the NPY gene which confers 48 nucleotides;
nuclear
induction
as a 98 bp-element analysis
48 h induced
shown).
NPY-CAT plasmids
further
for
pUCATNPY (-2.9kb/+397b)
of NGF for
that
(data
the
previous
M, indicating
NGF receptor
NGF (50ng/ml)
of
The ED50 value
10-l’
For
with
activity
and CAMP-stimu-
to APl
(-72/-65;
5’-
TGACTGCC-3’), AP2 (-65/-58; 5’-CCCCGAGG-J’), zif268 (NGFIA) (-68/-60; 5’TGCCCCCGA-3’). and Spl (-57/-51; 5’-CCCCTCC-3’) consensus sequences in NGFRE (Fig.
2).
Especially
100% identical
the putative
between
APl and Spl consensus-like
human and rat,
whereas
neither
sequences
AP2 nor
are
NGFIA con-
sensus sequence is conserved in the human gene (17, 18). This NGFRE is not similar to the cis-elements of other genes which confers NGF-stimulated transcription, such as vgf gene (19). 1555
vol.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
189, No. 3, 1992 A
-3k
-4k CAT fold-increase
b
1 Kpn
I Xba
-2k I I Hint
-1k
lk
Cap 8 I Nhe
IV Xho
--.
Sph
%itc
---I
7.1f0.6
1
8.5fl.6
I C& I CAT
7.0f0.7
4.0~0.8
I
f
CAT
4.2i0.2 4.1a0.7 6.6~1
.O
NGF-RE
B
I-
6
PUCAT NGFl -60/+16
pUCAT NGFP -62/+16
pUCAT NGF3 -32/+16
pUCAT (NGF3)3
pUCATSV1
C-32/+16)3
Fig.1. Deletion analysis of NPY promoter function in PC12 cells. Plasmids containing different fragments of the NPY 5’ upstream region ligated to the CAT gene were introduced into PC12 cells by CaPO -glycerol transfection, and their CAT activities in the presence of NGF 4 50 rig/ml) were compared to those in the absence of NGF. (A) Structures of NPYCAT fusion plasmids and NGF-induced CAT activity. Various pUCATNPY Materials and Methods. plasmids were constructed as described in In each plasmid, the 3’ end of the NPY gene is positioned at +397 (SphI) or +18 (Sac11 from the Cap site. The upstream regions varying from -3.3kb to -8Ob were fused to CAT gene as indicated. The NGF-induction in CAT activity is indicated as fold-increase (mean + SEM) in the left. The NGF response element was narrowed between -80 and +18. (B) NGFinduction of CAT activity of pUCATNGF plasmids. pUCATNGF reporter plasmids with restricted promoter regions of the NPY gene in the pUCATSV1 vector were constructed by PCR. Open and closed columns represent control and NGF-treated groups, respectively. The inserted regions are shown under the columns. pUCAT(NGF313 has three tandem
repeats of the fragment
(-32/+16) in front
of the CAT coding region.
To identify the DNA-binding proteins to NGFRE, we synthesized two oligonucleotides which include the imperfect palindromic structure (-61/-521, designated NGFUds (upstream; -8O/-51) and NGFDds (downstream; -62/-331, and As shown in Fig. 3, performed the gel retardation assay (Fig. 2 and 3). 1556
Vol.
189,
No.
3, 1992
BIOCHEMICAL
AND BIOPHYSICAL
RESEARCH COMMUNICATIONS
-80
CCCGGGCGTGACTGCCCCCGAGGCCCCTCCTGCCGCGACAAGGGCG-~~ . * -80 .
NGFUds
-5 1 * -62 .
NGFDds
-33 *
Fig.2. NGF response element (NGFRE)of the rat NPY gene. The sequence between -80 and -33. the evolutionarily conserved regions (APl- and Spl-like), and the imperfect palindromic structure (t-H ) are shown. The arrows indicate the two oligonucleotides (NGFUds and NGFDds) used for the gel retardation assay.
there
were found
specifically, molar
excess
binding
at
least
in the of
two proteins,
nuclear
extracts
each unlabeled
of nuclear
proteins
complex
was completely
inhibited
stream)
oligonucleotide
(Fig.
the
palindromic
loo-fold
molar
NGFRE (-80/-33)
One hundred-fold completely
the
NGFUds and NGFDds, respec-
using
loo-fold
32P-labeled molar
3B), suggesting
portion
that
of 32P-labeled
NGFDds (down-
excess
of
a nuclear NGFDds.
NGFUds (upprotein
could
The binding
pro-
since the Spl protein can bind the proteins, (5’-CCCCTCC-3’) in the human NPY gene (18) and
teins seemed to be Spl-like Spl consensus-like sequence also
by
to
suppressed
to the 32P-labeled
stream) to
can bind
PC12 cells.
oligonucleotide
tively (Fig. 3A and 3B). The formation of DNA-protein
bind
which
of the
excess of cold
GGCGGGGCGATC-3’) suppressed
Spl consensus
formation
of
sequence
DNA-protein
(5’-GATCGATCGG-
complex
(data
not
shown). The specific abundant
binding
(by lo-20-fold)
to 32P-labeled NGFRE-binding
binding
bind
proteins
that
(Fig.
proteins
portion
3’) and the
than
NGFUds was hardly
NGFDds oligonucleotide the upper
of nuclear
to NGFUds (upstream)
to NGFDds (downstream). inhibited
3A).
This
to the upper proteins
and this
(by 5%) by the addition indicated
that
portion
(-80/-63)
possess APl consensus-like of nuclear
were more
to
sequence this
portion
most
binding of cold
(95%) of
of NGFRE.
(-72/-65;
the Since
5’-TGACTGCC-
was competed
with
loo-fold molar excess of the APl consensus sequence (5’-CTAGTGATGAGTCAGCCGGATC-3’) by 92% (data not shown), the binding proteins to NGFUds seem A single band formation with Spl and APl consento be the APl protein. sus-like
sequences
in NGFUds shown
in Fig. 3A could be separated Thus there are at least two
acrylamide gel (data not shown). proteins which bind to the APl consensus-like consensus-like sequences in NGFRE, respectively. 1557
(more
abundant)
on 10% nuclear and
Spl
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Vol. 189, No. 3, 1992
A
NGFUds
NE.(,,g)
-
10
10
10
Competitor
-
-
u
D
-
10
-
-
Free
10
D
C
NGFComp
Free
NGFUds
”
C
NGF Comp
NGFDds
PC 12 cells
.~
oc
10
0
4
a
24 Time (hr)
Binding to Gel retardation assay with NGFRE oligonucleotides. the 5’ end-labeled 30-bp double-stranded oligonucleotides (NGFUds c-80/51) (A) and NGFDds t-62/-33) (B)) were performed with equal amounts of nuclear extracts (10 ,ug of protein) of PC12 cells. Competitions were performed with a 100x excess of competitor (U:NGFUds, D;NGFDds). The (C) NGF-induction of DNAarrows indicate the DNA-protein complex. protein complexes. PC12 cells were treated with or without NGF (50ng/ml) for 24 h. Ten fig of nuclear protein from treated (NGF) or untreated (C) cells were used for gel retardation assay, Comp means that a loo-fold molar excess of cold oligonucleotide was present in the assay of the NGF-treated sample. (D) Time course of NGF-induced change of binding activity. PC12 cells were cultured with or without NGF (50 rig/ml) for indicated periods and then nuclear extracts were prepared. The specific bands of DNA-protein complexes using NGFUds and NGFDds were quantitated as described in Materials and Methods. Data are mean of 3-4 independent samples. Fig.3.
We designated
binding (-72/-65) Next by NGF sus-like whereas tally
these
nuclear
proteins
as NDFl
(NGF-induced
nuclear
DNA-
protein factor-l) and NDF2. which may bind the APl consensus-like and the Spl consensus-like t-57/-51) elements, respectively. we investigated the change in binding activities of NDFl and NDF2 treatment (Fig. 3C and 3D). The binding of NDF2 to the Spl consenelement did not change (at most 120% 24 h after NGF treatment), that of NDFl to the APl consensus-like sequence increased biphasi-
upto
254% until
24 h in NGF-treataed
1558
PC12 cells
(Fig.
3D).
Vol.
189,
BIOCHEMICAL
N’o. 3, 1992
Although
NDFl seemed to
possibility
of
formation
unidentified
of
AND BIOPHYSICAL
be APl APl-like
DNA-protein
complex
proteins
is
c-Fos not
typical
increased
(data
sequence
(5’-GATCTCGCGGGGGCGAGGGGGATC-3’(loo-fold )
are
the NDFl binding
necessary
to
Interestingly
moderately
characterize
the
cold
(data not binding
and c-Jun),
excluded, APl
only
treatment inhibited
shown).
(e.g.
by using
(5’-CTAGTGATGAGTCAGCCGGATC-3’) was not
proteins
RESEARCH COMMUNICATIONS
since
consensus
within zif268
4h
the
element
after
NGF
(NGFIA) consensus
molar
excess)
shown). Further
proteins
the
to
the
also
experiments NGFRE in
the
NPY gene promoter. The data nuclear
proteins
NPY gene. of
suggested Actually
weaker
this than
the
increase
(NDFl) is essential
TK promoter
However,
that
an inverted
CAT gene of whole
DNA-binding
NGF-stimulated
activity
via
sequence (-80/-631 exhibited an enhancer
the
upper
NGFRE element,
portion
of
transcription
repeat
(20) still
transactivation that
for
in
the of the
ligated in front characteristics.
of NGFRE is relatively
as the CAT reporter
gene with
an
inverted repeat sequence (-80/-63) showed 1.9-fold induction of CAT activity by 48 h-NGF treatment (data not shown). Therefore it is suggested that the increase tant
but
in the binding not
enough
of NDFl to the APl consensus-like for
full
NGF-inducibility
pUCATNGF2 (-62/+16) plasmid
still
and
synergistically
NDF2 probably
The identification like)
proteins
NGF stimulates
exert
transcription
the
on of
to understand of
the
NGF-induced
NDFl (APl-like) the molecular
NPY gene
through
is impor-
NPY gene.
have a weak NGF-inducibility
and characterization are inevitable
of
element
As the (Fig. lB), NDFl
transactivation. and NDF2 (Splmechanism of how high-affinity
NGF
receptor.
REFJXRENCES 1. Kaplan, D. R., Hempstead, B. L., Martin-Zanca, D., Chao, M. V. and Parada, L. F. (19911 Science 252, 554-558. 2. Li, B.-Q., Kaplan, D., Kung, H. and Kamata, T. (1992) Science 256, 1456-1459. 3. Wood, K.W., Sarnecki, C., Roberts, T. M. and Blenis, J. (1992) Cell 68, 10411050. 4. Milbrandt, J. (1987) Science 238, 797-799. 5. Crosby, S. D., Veile, R. A., Donis-Keller, H., Baraban, J. M., Bhat, R. V., Simburger. K. S. and Milbrandt, J. (1992) Proc. Natl. Acad. Sci. USA 89, 4739-4743. 6. Sabol, S. L. and Higuchi, H. (1990) Mol. Endocrinol. 4, 384-392. 7. Higuchi, H., Costa, E. and Yang, H.-Y. T. (1988) J. Pharmacol. Exp. Ther. 244, 468-474. 8. Higuchi, H., Yang, H.-Y. T. and Costa, E. (1988) J. Neurochem. 50, 18791886. 9. Higuchi, H., Iwasa, A., Yoshida, H., and Miki, N. (1990) Mol. Pharmacol. 38, 614-623. 10. Higuchi, H., Yokokawa, K., Iwasa, A., Yoshida. H., and Miki, N. (1991) J. Neurochem. 57, 1840-1847. 11. Allen, J. M. and Koenig, J. I. (1990) Annals New York Acad. Sci. Vol. 611.. 1559
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BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMilNlCATlONS
12. M isaki. N.. Higuchi, H., Yamagata. K., and M iki, N. (1992) Neurochem. Int. 21, 185-189. 13. Dignam. J. D., Lebowitz, R. M . and Roeder, R. G. (1983) Nucleic Acids Res. 11, 1475-1489. 14. Bradford, M . M . (1976) Anal. Biochem. 72, 248-254. 15. Osugi, T., Taniura, II.. Ikemoto, M . and M iki, N. (1991) Biochem. Biophys. Res. Commun.174, 25-31. 16. Higuchi, H., Yang, H.-Y. T., and Sabol, S. L. (1988) J. Biol. Chem. 263, 6288-6295. 17. Larhammar, D., Ericsson, A. and Persson, H. (1987) Proc. Natl. Acad. Sci. USA 84, 2068-2072. 18. M inth, C. D., and Dixon, J. E. (1990) J. Biol.Chem. 265, 12933-12939. 19. Possenti, R., Di Rocco, G.. Nasi, S. and Levi, A. (1992) Proc. Natl. Acad. Sci. USA 89. 3815-3819. 20. Luckow, B. and Schitz, G. (1987) Nucleic Acids Res. 15, 5490.
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