 |
Previous Article
Volume 17, Number 24,
Issue of December 15, 1997
Effects of Sleep on Wake-Induced c-fos Expression
Radhika Basheer1,
Jonathan E. Sherin2,
Clifford B. Saper2,
James
I. Morgan3,
Robert W. McCarley1, and
Priyattam J. Shiromani1
1 VA Medical Center and Harvard Medical School,
Brockton, Massachusetts 02401, 2 Department of Neurology,
Beth Israel-Deaconess Hospital, Boston, Massachusetts 02215, and
3 Department of Developmental Neurobiology, St. Jude
Children Research Hospital, Memphis, Tennessee 38105
ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
FOOTNOTES
REFERENCES
ABSTRACT
We investigated the effects of sleep on wake-induced
c-fos expression in the cerebral cortex of rats and
c-fos-lacZ transgenic mice. In the cortex of rats, the
levels of c-Fos, detected both by immunocytochemistry and Western blot,
remained high during 6 or 12 hr of enforced wakefulness but declined
rapidly (within 1 hr) with increasing time of recovery sleep.
Similarly, in the transgenic mice in which lacZ
expression is driven from the c-fos promoter,
-galactosidase activity was high after enforced wakefulness and
declined with increasing amounts of sleep. These results suggest that
the decrease in c-Fos protein in cortical neurons during sleep may be
attributable to cessation of c-fos expression,
activation of a process that degrades the wake-induced c-Fos, or
both.
Key words:
sleep;
c-fos expression;
c-fos-lacZ
transgenic mice;
cingulate cortex;
immunohistochemistry;
Western blot;
-gal activity
INTRODUCTION
Sleep and wakefulness are marked by
dramatic shifts in neuronal firing. During wakefulness most brain
neurons, including cortical neurons, are active, whereas non-rapid eye
movement (REM) sleep is marked by a relatively quiescent and
distinctively different pattern of neuronal activity. Such shifts in
neuronal firing and the accompanying release of neurotransmitters most
likely produce alterations at the molecular level.
To find evidence that gene expression occurs during sleep-wakefulness,
investigators have examined the cellular immediate early gene
c-fos. This gene is rapidly and transiently induced in
response to various stimuli (for review, see Morgan and Curran, 1991 ).
The expression of c-fos has also been shown to change in different parts of the brain during spontaneous sleep-wake episodes (Cirelli et al., 1993a ; Pompeiano et al., 1994 ; Grassi-Zucconi et al.,
1994 ; Sherin et al., 1996 ). Fos protein levels in the cortex and other
parts of the rat brain are high during the dark period when rats are
awake and low during the light period when rats are asleep
(Grassi-Zucconi et al., 1993 ). Moreover, enforced wakefulness increases
c-Fos levels in cortex, and with ensuing sleep there is a decline of
c-Fos in rats (Pompeiano et al., 1992 ; Cirelli et al., 1993b , 1996 ) and
in cats (Shiromani et al., 1994 ). Cirelli et al. (1996) recently
demonstrated that the wake-induced c-fos expression in
cortical neurons is dependent on noradrenergic input from the locus
coeruleus (LC).
We investigated the effects of recovery sleep on enforced wake-induced
c-Fos immunoreactivity (c-Fos-ir) using immunocytochemistry and Western
blot techniques. Transgenic c-fos-lacZ mice with
the bacterial gene lacZ, encoding -galactosidase
( -gal), fused into the fourth exon of c-fos (Smeyne et
al., 1992 ), were also studied. An increase in -gal activity and
c-Fos protein occurred during enforced wakefulness, indicating
activation of c-fos expression. In addition, there was a
decrease in -gal activity and c-Fos-ir with sleep. This suggests
that during sleep there is a cessation of c-fos expression,
an activation of a proteolytic pathway that degrades c-Fos in
wake-active neurons, or both. The time course of the sleep-induced
decline of c-Fos in rats and mice resembles the time course described
in cats (Shiromani et al., 1994 ), suggesting a similar process across
different species.
MATERIALS AND METHODS
Animals and sleep deprivation paradigm. Rats and mice
used in this study were housed in a room with controlled temperature (21°C) and a 12 hr light/dark cycle (lights on 7:00 A.M.), with food
and water provided ad libitum.
The first set of experiments was performed using male Sprague Dawley
rats (300-350 gm). Surgical implantation of sleep-recording electrodes
was done under anesthesia [mixture of (in mg/kg): 0.75 acepromazine,
2.5 xylazine, and 22 ketamine]. One week after recovery from surgery,
the animals were connected to flexible cables that permitted
undisturbed recording of sleep-wake episodes. After 3 d of
adaptation to the recording cables the experimental paradigm was
started. The rats were kept awake for 12 hr (7:00 A.M.-7:00 P.M.) by
gently touching them or by tapping the cage whenever the animals
produced EEG signs of sleep. Six animals were killed after the 12 hr
period of wakefulness (0% sleep), and the rest were allowed 1 hr of
recovery sleep (n = 7), during which the rats
spontaneously slept 0-95% of the time. The EEG records were scored in
12 sec epochs (paper speed, 5 mm/sec) for wakefulness and non-REM and
REM sleep. All animals were perfused transcardially with 50 ml of
ice-cold normal saline followed by 350 ml of ice-cold 2% formaldehyde
in 0.1 M PBS. The brains were removed, placed overnight in
the same fixative, and then transferred and stored in buffer containing
20% sucrose and 0.1 M PBS, pH 7.4, at 4°C for
immunohistochemical analysis.
A second set of experiments was performed using c-fos-lacZ
transgenic mice (Smeyne et al., 1992 ). In these mice a bacterial -galactosidase (lacZ) gene was fused in frame into the
C-terminal region of the c-fos gene. The c-Fos-lacZ fusion
protein expressed from the c-fos promoter contains 315 N-terminal amino acids from c-Fos and 1015 C-terminal amino acids from
-galactosidase. As a result, these transgenic mice can be
used for the simultaneous detection of both c-Fos protein and
-galactosidase activity in adjacent sections.
A total of 16 mice were used. Wakefulness was prolonged (10:00
A.M.-1:00 P.M.) by gentle handling of the animals. Six mice were
killed after 3 hr of prolonged wakefulness, and the remaining 10 mice
were allowed 1 hr of recovery sleep. The amount of sleep and
wakefulness was determined by behavioral observations as described by
Franken et al. (1992) . If the animals were immobile, i.e., without
gross body, head, or whisker movements, then they were considered to be
asleep and were awakened by tapping the cage or by gentle touch. During
recovery sleep, such periods of immobility were followed by the animal
rapidly assuming a curled sleep posture.
c-Fos immunohistochemistry. Coronal sections (40 µm thick)
were cut with a freezing microtome. For detection of Fos-ir, a rabbit
polyclonal antiserum (Santa Cruz Biotechnology, Santa Cruz, CA) was
used at a 1:1000 dilution. Control sections were processed without
primary or secondary antibodies. Antibodies for c-Fos from other
sources (Oncogene Science) yielded similar results. The sections (one
in four series) were washed with 0.1 M PBS containing 0.25% Triton X-100 and then incubated overnight at room temperature in
the presence of antibody. The following day the sections were washed in
0.1 M PBS and incubated with anti-rabbit secondary antibody (donkey anti-rabbit serum). After washing, the sections were incubated for 1 hr in avidin-biotin complex (ABC kit; Vector Laboratories, Burlingame, CA) followed by washes and 5 min of treatment with the
chromogen DAB-nickel chloride-hydrogen peroxide solution (Vector). The
sections were then mounted onto gelatin-coated slides and coverslipped
after dehydration in alcohol-xylene solutions.
-Galactosidase histochemistry. Sections (40 µm thick)
were cut with a freezing microtome, and visualization of -gal
activity was performed as described by Oberdick et al., (1990) .
Briefly, the sections were mounted on gelatin-coated slides and air
dried. Sections were stained for 16-20 hr at 37°C in the dark with
5-bromo-4-chloro-3-indolyl- -D-galactosidase (X-gal;
Boehringer Mannheim, Indianapolis, IN) to determine -gal activity.
Adjacent sections were stained for Fos-ir as described above.
Quantitation of labeled nuclei. c-Fos- or -gal-labeled
cells from the cingulate cortex were counted. Darkly labeled cells were
counted in a 100 × 300 µm area from one cortical hemisphere. Counts were done on 8-10 tissue sections (one in four series), and an
average count per section was determined for each animal.
Western blot analysis. In another set of experiments, for
Western blot analysis, rats were killed by rapid decapitation at 7:00
P.M. (lights off) after 6 hr of prolonged wakefulness (1:00-7:00 P.M.)
(n = 4) or after 1 hr of recovery sleep (n = 4). The cortical tissue samples were dissected and frozen in liquid
nitrogen. Nuclear extracts from cortical tissue were prepared as
described by Sonnenberg et al., (1989) . Tissue was homogenized in a
Dounce homogenizer in 10 vol 0.25 mM sucrose, 15 mM EGTA, 0.15 mM spermine, 0.5 mM spermidine, 5 mM DTT, 2 µg/ml leupeptin, 5 µg/ml
aprotinin, and 0.2 mM PMSF. The homogenates were
centrifuged at 2000 × g for 6 min at 4°C, and the
pellets were resuspended in the original volume of (in mM):
10 HEPES, pH 7.9, 1.5 MgCl2, 10 NaCl, and 5 DTT,
containing protease inhibitors. After centrifugation at 4000 × g for 10 min at 4°C, the nuclear pellets were resuspended
in 50 mM HEPES, pH 7.9, 0.75 mM
MgCl2, 0.5 mM EDTA, 0.5 M
NaCl, 12.5% glycerol, 5 mM DTT, and protease inhibitors
and incubated on a rotating shaker for 1 hr at 4°C and centrifuged at
15,000 × g for 30 min. The supernatant containing the
final nuclear extract was dialyzed overnight at 4°C in 5 mM Tris-HCl, pH 7.9, and 0.1 mM PMSF and
lyophilized. The pellets were resuspended in water, and protein content
was estimated using the Bradford method. Protein samples (50 µg) were
electrophoresed in 10% SDS-PAGE at 150 V for 3 hr. The samples were
electroblotted overnight at 20 V onto nitrocellulose membranes. The
membranes were blocked using 3% nonfat dry milk in PBST buffer (10 mM sodium phosphate, pH 7.4, 150 M sodium
chloride, and 0.1% Tween-20) and incubated overnight on a shaker with
anti-c-Fos rabbit antibody (SC-52G) at 1:1000 dilution (Santa Cruz
Biotechnology). A 62 kDa band was identified as c-Fos protein. In
control experiments this band disappeared after preincubation with the
blocking peptide (SC-52P) recommended by the manufacturer (Santa Cruz
Biotechnology). The next day the blots were washed using PBST and
incubated for 1 hr with anti-rabbit, peroxidase-conjugated, secondary
antibody. The protein bands were detected using an ECL detection kit
(Amersham, Arlington Heights, IL) as described by the manufacturer.
RESULTS
Fos-ir decreases with sleep
Fos-ir was elevated in the cingulate cortex of rats kept awake for
12 hr compared with animals that were permitted to sleep after enforced
wakefulness (Fig.
1A,B). The number of
Fos-positive neurons was inversely related to the percentage of total
sleep (slow wave plus REM sleep, r = 0.82;
p < 0.005) during the hour preceding death (Fig.
2). Similar results were observed in
another set of experiments in which c-Fos-ir concentration was high in the cortex after 6 hr of enforced wakefulness. The number of c-Fos-ir cells decreased after 1 hr of recovery sleep (data not shown).
Fig. 1.
Immunohistochemical detection of c-Fos in
cingulate cortex. Rats were kept awake by gentle handling for 12 hr
(7:00 A.M.-7:00 P.M.) and then killed (n = 6) or
allowed 1 hr of sleep (n = 7). c-Fos-labeled cells
in cingulate cortex were detected using immunohisochemistry after
prolonged wakefulness (A) and after 1 hr of sleep
(B).
[View Larger Version of this Image (151K GIF file)]
Fig. 2.
Enforced wakefulness and recovery from
sleep-induced changes in the number of c-Fos-positive neurons in
cortex. The number of c-Fos-positive cells was counted in cingulate
cortex of rats that were kept awake for 12 hr or were allowed sleep
after enforced wakefulness. Percent of sleep was calculated as total
sleep time/60 min × 100. c-Fos levels declined in those animals
who slept when they were permitted (n = 7) compared
with those animals not permitted to sleep (n = 6).
The number of c-Fos-positive cells declined with increasing percentage
of sleep (n = 13; r = 0.82;
p < 0.005).
[View Larger Version of this Image (19K GIF file)]
To determine whether the antibody recognizes the 62 kDa c-Fos protein,
Western blot analysis was used to compare the level of c-Fos in
cingulate cortex from rats that were kept awake or allowed 1 hr of
recovery sleep. Figure 3 shows that the
antibody detected a 62 kDa c-Fos protein that selectively decreased
after sleep. This size is consistent with other studies of c-Fos
(Curran and Morgan, 1986 ). Other bands of Fos-related antigens (FRAs) at 35 and 47 kDa did not decrease in cortical extracts of rats killed
after 1 hr of recovery sleep.
Fig. 3.
Western blot analysis of nuclear proteins. To
determine the size of c-Fos protein, Western blot analysis was
performed using tissue extracts of cingulate cortex from rats after 6 hr of enforced wakefulness (SD1, SD2), and followed by 1 hr of sleep (RS1, RS2) before death. c-Fos protein
(molecular weight, 62 kDa; arrowhead) decreased in rats
that were allowed sleep before death.
[View Larger Version of this Image (117K GIF file)]
Decrease in -Galactosidase activity after 1 hr of
recovery sleep
Similar results were obtained with c-fos-lacZ mice. The
-gal activity in cingulate cortex was high after 3 hr of enforced wakefulness (Fig. 4A)
and declined significantly after 1 hr of recovery sleep (Fig.
4B). The -gal activity decreased as a function of
the time spent sleeping (Fig. 5)
(r = 0.72; p < 0.001). Figure 6 shows the time spent sleeping before
death for two representative mice. One exhibited high levels of
-gal-positive neurons; this animal did not sleep when permitted
(mouse 7), whereas another showed a loss of activity after 45 min of
sustained sleep (mouse 10). Because -gal is driven from the
c-fos promoter, this result supports the conclusion that
c-Fos (rather than or in addition to a Fos-related antigen) is elevated
during wakefulness.
Fig. 4.
Detection of -galactosidase activity in
cingulate cortex. The presence of -gal activity in the cingulate
cortex of c-fos-lacZ transgenic mice was detected using
x-gal after 3 hr of enforced wakefulness (A) and
then followed by 1 hr of sleep (B).
[View Larger Version of this Image (116K GIF file)]
Fig. 5.
Sleep-induced decrease in -galactosidase
activity. The number of cells showing -gal activity was correlated
with the percent of sleep during the 60 min period before death of
c-fos-lacZ transgenic mice. -Galactosidase activity
decreased with increasing amount of sleep (n = 16;
r = 0.72; p < 0.001).
[View Larger Version of this Image (23K GIF file)]
Fig. 6.
The wake-sleep profile of two representative
mice. Both mice were kept awake for 3 hr and then left undisturbed for
1 hr. Mouse 7 did not sleep even when permitted to do so, and high
levels of -galactosidase staining were found in the cingulate
cortex. Mouse 10 was asleep for 45 min before death, and it showed no -galactosidase stained cells. The hatched bar
represents 3 hr period of enforced wakefulness.
[View Larger Version of this Image (24K GIF file)]
DISCUSSION
Several studies have found that the expression of c-fos
(mRNA and protein) is increased in many brain regions during
spontaneous (Cirelli et al. 1993a ; Grassi-Zucconi et al. 1993 , 1994 ;
Pompeiano et al. 1994 ; Sherin et al. 1996 ) or enforced wakefulness in
rats (Pompeiano et al. 1992 ; O'Hara et al. 1993 , Cirelli et al. 1995 , 1996 ). Similarly in cats, Fos-ir increases with 24 hr of enforced wakefulness and declines after 45 min of recovery sleep (Shiromani et
al. 1994 ). The levels of c-fos expression have been
determined in different species, using various techniques, and for
different durations of enforced wakefulness. However, in these reports, c-Fos was detected only by immunohistochemical analysis using polyclonal antisera against c-Fos. Such antisera can cross-react with
other FRAs. Using Western blot analysis, we demonstrated that the
increased Fos-ir during enforced wakefulness and its reduction during
sleep are specific for 62 kDa c-Fos. This was further confirmed in
c-fos-lacZ mice showing similar changes in -gal
expression, which is transcribed from the c-fos promoter. In
addition, in previous studies the animals were examined immediately at
the end of the enforced-wake period. Therefore, the effects of short
periods of ensuing sleep on wake-induced c-Fos levels were not
examined. The present study was conducted to clarify further the
effects of sleep on wake-induced c-Fos levels.
Specifically, the present study examined c-Fos during the 1 hr sleep
period immediately before death. This provides important insight into
the dynamics of c-fos transcription and degradation in
response to rapidly changing sleep-wake conditions. A previous study
(Pompeiano et al., 1994 ) examined c-fos (mRNA and protein) in rats that were killed after a 5 hr period of spontaneous
sleep-wakefulness (either in the day or night). In that study, c-Fos
was found to be lower in rats that were asleep 80% of the 5 hr period
compared with rats that were asleep 25% of the 5 hr period.
Grassi-Zucconi et al. (1994) measured sleep-wakefulness during a 4 hr
period and also found that c-Fos levels decreased with sleep. Our
results are similar in that there was a decrease in c-Fos in response to sleep. However, by using a 1 hr sleep period, the temporal decline
in c-Fos can be better understood.
It was observed that in c-fos-lacZ transgenic mice, in which
lacZ expression is driven from the c-fos
promoter, -gal activity was high in awake mice but declined with
increasing amounts of sleep. Although mRNA levels were not examined in
this study, other investigators have observed a decrease in
c-fos mRNA with sleep using Northern blot and in
situ hybridization (Grassi-Zucconi et al. 1993 ; Cirelli et al.
1995 ), which is indicative of the levels of mRNA at the time of death.
Our results with c-fos-lacZ mice also showed a decrease in
sleep-related -galactosidase activity. Observations of both
endogenous Fos and the fusion transgene thus support the conclusion
that sleep is associated with reduced transcription from the
c-fos promoter, or increased degradation of c-fos
mRNA, which has a short half-life because of the Shaw-Kamen degradation sequence (AUUUA) in its 3 -untranslated region (Gillis and Malter, 1991 ). It is difficult to determine the relative contributions of these
two processes.
The molecular events leading to the initiation of c-fos gene
transcription include phosphorylation of the c-AMP response element binding (CREB) protein, bound to CRE sequence upstream from the c-fos promoter (Morgan and Curran, 1991 ). An increase in
phosphorylated CREB throughout the brain after wakefulness was observed
by us (unpublished data) and Cirelli et al. (1996) . Another report
(Cirelli and Tononi, 1996 ) has shown an increase in serine/threonine
kinase-specific phosphorylation in wakefulness. Activation of such
events might, in part, be attributable to noradrenergic stimulation
(Cirelli et al.,1996 ). Because during sleep neuronal activity in the LC is considerably reduced (McCarley and Hobson, 1975 ; Aston-Jones and
Bloom, 1981 ), it is possible that a decline in norepinephrine tone from
the LC may result in a reduction of CREB phosphorylation and a
subsequent decline in c-fos expression. Our results using c-fos-lacZ mice also showed a sleep-induced decrease in
-gal activity, suggesting a decrease in transcription from the
c-fos promoter during sleep.
Our observation, that after 1 hr of sleep, not only Fos-ir but also
-gal activity is decreased, is instructive. Pulse-chase studies
performed on PC12 cells showed that Fos degrades with a half-life of
~45 min but is still detectable after 2 hr (Curran and Morgan, 1986 ).
In B104 cells, Fos-lacZ has a longer half-life than that of endogenous
c-Fos (Schilling et al., 1991 ). Such studies are difficult to perform
in vivo. However, in c-fos-lacZ rats the -gal
activity in hippocampus and cortex after pentylenetetrazole (PTZ)
treatment was highest at 2 hr and declined after 3 hr but was still
detectable at 4 hr (Kasof et al., 1995 ). Moreover, in those studies the
disappearance of Fos-ir was faster than -gal activity after PTZ
treatment. Our observations indicate that after 1 hr of sleep, both
Fos-ir and -gal activity are reduced. This strongly suggests the
possibility of activation of a proteolytic pathway during sleep that
targets both Fos and the Fos-LacZ fusion protein. Rechsteiner and
Rogers (1996) have proposed that the presence of polypeptide sequences
enriched in proline (P), glutamic acid (E), serine (S), and threonine
(T) (PEST) in c-Fos renders it more susceptible to proteolytic
degradation. There is also emerging evidence that Fos is eliminated by
ubiquitinylation (Hermida-Matsumoto et al., 1996 ). The decline in Fos
and -gal staining with sleep shows that the fused protein that is
detected in the nucleus is degraded in its entirety. In addition,
-galactosidase does not contain PEST sequence. It is therefore more
likely that the fusion protein is ubiquitinylated, resulting in its
total degradation by trafficking to the proteosome. The exact nature of
this pathway and its possible activation at the onset of sleep is yet
to be studied.
Our results thus confirm previous observations that levels of Fos
increase during enforced wakefulness. These levels decrease within 1 hr
of sleep. The regulation of transcription of c-fos and
activation of putative proteolytic pathways may contribute to these
changes. These observations demonstrate that the regulation of gene
expression and modulation of their protein products can occur with
short periods of sleep. Moreover, this process appears to be similar
across different species.
FOOTNOTES
Received Aug. 11, 1997; revised Oct. 1, 1997; accepted Oct. 7, 1997.
This research was supported by the Veterans Administration Medical
Research Service and National Institutes of Health Grant NS30140.
J.I.M. was supported in part by National Institutes of Health Cancer
Center Support CORE Grant P30 CA21765 and by the American Lebanese
Syrian Associated Charities. Parts of this study were presented at the
1995 Annual Meeting of The Society for Neuroscience. We thank Dr Mahesh
Thakkar for helpful discussions.
Correspondence should be addressed to Priyattam J. Shiromani, Veterans
Administration Medical Center and Harvard Medical School, Research 151, 940 Belmont Street, Brockton, MA 02401.
REFERENCES
-
Aston-Jones G,
Bloom FE
(1981)
Activity of norepinephrine-containing locus coeruleus neurons in behaving rats anticipates fluctuations in the sleep-waking cycle.
J Neurosci
1:876-886[Abstract].
-
Cirelli C,
Tononi G
(1996)
Changes in protein phosphorylation patterns in the brain during the sleep-waking cycle.
Soc Neurosci Abstr
22:688.
-
Cirelli C,
Pompeiano M,
Tononi G
(1993a)
Fos-like immunoreactivity in the rat brain in spontaneous wakefulness and sleep.
Arch Ital Biol
131:327-330[Web of Science][Medline].
-
Cirelli C,
Pompeiano M,
Tononi G
(1993b)
Fos expression in the rat brain after variable periods of sleep deprivation.
Sleep Res
22:595.
-
Cirelli C,
Pompeiano M,
Tononi G
(1995)
Sleep deprivation and c-fos expression in the rat brain.
J Sleep Res
4:92-106.[Web of Science][Medline]
-
Cirelli C,
Pompeiano M,
Tononi G
(1996)
Neuronal gene expression in the waking state: A role for the locus coeruleus.
Science
274:1211-1215[Abstract/Free Full Text].
-
Curran T,
Morgan JI
(1986)
Barium modulates c-fos expression and post-translational modification.
Proc Natl Acad Sci USA
83:8521-8524[Abstract/Free Full Text].
-
Franken P,
Tobler I,
Borbely AA
(1992)
Cortical temperature and EEG slow-wave activity in the rat: analysis of vigilance state related changes.
Pflügers Arch
420:500-507[Web of Science][Medline].
-
Gillis P,
Malter PS
(1991)
The adenosine-uridine binding factor recognizes the AU-rich elements of cytokine, lymphokine and oncogene mRNAs.
J Biol Chem
266:3172-3177[Abstract/Free Full Text].
-
Grassi-Zucconi G,
Menegazzi M,
Carcereri De Prati A,
Bassetti A,
Montagnese P,
Mandile P,
Cosi C,
Bentivoglio M
(1993)
c-fos mRNA is spontaneously induced in the rat brain during the activity period of the circadian cycle.
Eur J Neurosci
5:1071-1078[Web of Science][Medline].
-
Grassi-Zucconi G,
Giuditta A,
Mandile P,
Chen S,
Vescial S,
Bentivoglio M
(1994)
c-fos spontaneous expression during wakefulness is reversed during sleep in neuronal subsets of the rat cortex.
J Physiol (Paris)
88:91-93[Web of Science][Medline].
-
Hermida-Matsumoto ML,
Chock PB,
Curran T,
Yang DCH
(1996)
Ubiquitinylation of transcription factors c-Jun and c-Fos using reconstituted ubiquitinylating enzymes.
J Biol Chem
271:4930-4936[Abstract/Free Full Text].
-
Kasof GM,
Mandelzys A,
Maika SD,
Hammer RE,
Curran T,
Morgan JI
(1995)
Kainic acid-induced neuronal death is associated with DNA damage and a unique immediate-early gene response in c-fos-lacZ transgenic rats.
J Neurosci
15:4238-4249[Abstract].
-
McCarley RW,
Hobson JA
(1975)
Neuronal excitability modulation over the sleep cycle: a structural and mathematical model.
Science
189:58-60[Abstract/Free Full Text].
-
Morgan JI,
Curran T
(1991)
Stimulus-transcription coupling in the nervous system: involvement of the inducible proto-oncogenes fos and jun.
Annu Rev Neurosci
14:421-451[Web of Science][Medline].
-
Oberdick J,
Smeyne RJ,
Mann JR,
Zackson S,
Morgan JI
(1990)
A promoter that drives transgene expression in cerebellar Purkinje and retinal bipolar neurons.
Science
248:223-226[Abstract/Free Full Text].
-
O'Hara BF,
Young KA,
Watson FL,
Heller HC,
Kilduff TS
(1993)
Immediate early gene expression in brain during sleep deprivation: Preliminary observations.
Sleep
16:1-7[Web of Science][Medline].
-
Pompeiano M,
Cirelli C,
Tononi G
(1992)
Effects of sleep-deprivation on Fos-like immunoreactivity in the rat brain.
Arch Ital Biol
130:325-335[Web of Science][Medline].
-
Pompeiano M,
Cirelli C,
Tononi G
(1994)
Immediate-early genes in spontaneous wakefulness and sleep: expression of c-fos and NGFI-A mRNA and protein.
J Sleep Res
3:80-96.[Web of Science][Medline]
-
Rechsteiner M,
Rogers SW
(1996)
PEST sequences and regulation by proteolysis.
Trends Pharmacol
21:267-271.
-
Schilling K,
Luk D,
Morgan JI,
Curran T
(1991)
Regulation of a fos-lacZ fusion gene: A paradigm for quantitative analysis of stimulus-transcription coupling.
Proc Natl Acad Sci USA
88:5665-5669[Abstract/Free Full Text].
-
Sherin JE,
Shiromani PJ,
McCarley RW,
Saper CB
(1996)
Activation of ventrolateral preoptic neurons during sleep.
Science
271:216-219[Abstract].
-
Shiromani PJ,
Winston S,
Malik M,
McCarley RW
(1994)
Rapid decline in Fos-LI in association with recovery sleep that follows total sleep deprivation.
Sleep Res
23:36.
-
Smeyne RJ,
Schilling K,
Robertson L,
Luk D,
Oberdick J,
Curran T,
Morgan JI
(1992)
fos-lacZ transgenic mice: mapping sites of gene induction in the central nervous system.
Neuron
8:13-23[Web of Science][Medline].
-
Sonnenberg JL,
Macgregor-Leon PF,
Curran T,
Morgan JI
(1989)
Dynamic alterations occur in the levels and composition of transcription factor AP-1 complexes and seizure.
Neuron
3:359-365[Web of Science][Medline].
This article has been cited by other articles:

|
 |

|
 |
 
S. Ribeiro and M. A.L. Nicolelis
Reverberation, storage, and postsynaptic propagation of memories during sleep
Learn. Mem.,
November 1, 2004;
11(6):
686 - 696.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Ribeiro, C. V. Mello, T. Velho, T. J. Gardner, E. D. Jarvis, and C. Pavlides
Induction of Hippocampal Long-Term Potentiation during Waking Leads to Increased Extrahippocampal zif-268 Expression during Ensuing Rapid-Eye-Movement Sleep
J. Neurosci.,
December 15, 2002;
22(24):
10914 - 10923.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Gong, R. Szymusiak, J. King, T. Steininger, and D. McGinty
Sleep-related c-Fos protein expression in the preoptic hypothalamus: effects of ambient warming
Am J Physiol Regulatory Integrative Comp Physiol,
December 1, 2000;
279(6):
R2079 - R2088.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Ribeiro, V. Goyal, C. V. Mello, and C. Pavlides
Brain Gene Expression During REM Sleep Depends on Prior Waking Experience
Learn. Mem.,
September 1, 1999;
6(5):
500 - 508.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
C. M. Novak and A. A. Nunez
Daily rhythms in Fos activity in the rat ventrolateral preoptic area and midline thalamic nuclei
Am J Physiol Regulatory Integrative Comp Physiol,
November 1, 1998;
275(5):
R1620 - R1626.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|

|