• Korean Journal of Veterinary Service
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• v.27 no.4
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• pp.355-369
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• 2004

The equine herpesvirus type 1 (EHV-1) immediate-early (IE) protein is a potent transactivator responsible for the activation of both early and late genes during the course of infection and is comprised of discrete functional domains that mediate its many functions. Interaction between trans activators such as the IE protein and various components of the RNA polymerase II transcription initiation machinery has been demonstrated to be critical for transactivation. In the present report, it is addressed the hypothesis that the IE protein interacts with various components of transcription machinery to mediate transactivation of target viral genes. In these studies, it is demonstrated that in vitro transcribed and translated IE protein interacts with TFIIB-agarose conjugate but not with TFIID-agarose conjugate. Additional immunoprecipitation studies using nuclear extracts derived from EHV-1 infected RK-13 cells confirmed that the IE protein interacts strongly with TFIIB, but fails to interact with TFIID. IR2, a truncated form of the IE protein lacking the potent transactivation domain and involved in the down-regulation of the IE gene, also interacted with TFIIB but not with TFIID. Studies were also performed to ascertain if particular TBP-associated factors (TAFs) could mediate IE or IR2 binding to TFIID. In vitro transcribed and translated TAF250 added to nuclear extracts generated from EHV-1 infected cells also failed to mediate an interaction between the IE protein or the IR2 protein and TFIID. This study demonstrated that the IE protein mediates transactivation of target viral genes by a mechanism that involves TFIIB. This is in contrast to mechanisms that have been proposed for both the herpes simplex virus ICP4 and VP16 protein which have been proposed to transactivate viral genes through interactions involving both TFIIB and TFIID. This study also intimates that IR2 mediate its repressive effects during the course of EHV-1 infection by a mechanism that involves sequestration of various transcription factors.

• Korean Journal of Microbiology
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• v.31 no.1
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• pp.72-78
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• 1993

Since the 'promoter/enhancer region of the major immediate early (IE) ~ene of human cytomegalovirus (HCMV) contains the cyclic AMP (cAMP) response element (CRE) consensus sequence, it was reasonable to hypothesize that cAMP might affect HCMV replication. Cyclic AMP modulating drugs such as 8-bromoadenosine 3',5'-cyclic monophosphate (BrA), and papaverine were used to affect the intracellular levels of cAMP, and the effects of the drugs on HCMV replication were studied. While papaverine effectively inhibited HCMV multiplication and DNA synthesis, BrA exerted little effect on the production of infectious HCMV yields. The synthesis of DNA in HCMV-infected cells appeared to be stimulated by BrA In order to understand the effect of cAMP on the expression of HCMV major IE gene, plasmid (pCMVIE/CAT) containing a reporter gene driven by HCMV IE promoter was transfected into either permissive human embryo lung (HEL) cells or nonpermissive cells. PL,Javerine, which has been reported to block the HCMV-induced increase in cAMP, reduced the expression of pCMVIE/CA T in permissive HEL cells. Treatment of transfected cells with BrA increased the expression of HCMV major IE promoter not only in HEL cells, but also in nonpermissive HeLa and Vero cells. Therefore, it seems that the expression of HCMV major IE gene is regulated by cAMP.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.5
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• pp.355-359
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• 2000

Cocaine induces immediate early gene expression and behavioral changes by blocking dopamine transporters in the terminals of nigrostriatal neurons in the striatum. The pharmacological role of serotonin 2/1C (5HT2/1C) receptors in cocaine-induced expression of zif268 (NGFI-A, egr1 and Krox-24) mRNA, a member of the zinc finger, was investigated using quantitative in situ hybridization histochemistry in vivo. Behavioral alterations induced by cocaine were also monitored in relation with blockade of the receptors. Systemic injection of ritanserin (1 mg/kg, s.c.), a 5HT2/1C receptor antagonist, did not reverse behavioral alterations and zif268 mRNA gene expression induced by 15 mg/kg cocaine, i.p., in the dorsal and ventral striatum. These data indicate that ritanserin-sensitive 5HT2/1C receptors are not necessary for cocaine-induced behavioral alterations and zif268 mRNA gene expression in the striatum.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.4
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• pp.299-305
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• 2001

Activation of D1-like dopamine receptors by psychostimulants, such as amphetamine, upregulates the expression of immediate early gene and opioid peptide gene in the striatum. The genomic changes are regulated by phosphorylated transcription factors via complicated intracellular events. To evaluate temporal expression of the transcription factors by dopaminergic stimulation, the D1-like dopamine agonist, amphetamine or SKF82958, was systematically delivered. As intracellular markers in response to the agonist, phosphorylated cAMP response element-binding protein (pCREB), Fos-related antigens (FRA) and FosB immunoreactivity (IR) was compared at 20 and 120 min time points in the selected areas of the striatum. Semi-quantitative immunocytochemistry showed that amphetamine (5 mg/kg, i.p.) significantly increased pCREB-IR at 20 min, sustained up to 60 min and decreased at 120 min after the infusion. Like amphetamine, the full D1 agonist, SKF82958 (0.5 mg/kg, s.c.), also increased pCREB-IR at 20 min, but not at 120 min after the infusion in the dorsal striatum (caudoputaman, CPu) and shell of ventral striatum (nucleus accumbens, NAc). In contrast, FRA- and FosB-IR induced by SKF82958 was significantly increased at 120 min, but not at 20 min after the administration. These data indicate that SKF82958 mimics induction of CREB phosphorylation by amphetamine and differentially regulates temporal induction of pCREB, and FRA and FosB expression in the striatum.

• Development and Reproduction
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• v.19 no.2
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• pp.61-67
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• 2015

The immediate early gene c-fos has long been known as a molecular marker of neural activity. The neuron's activity is transformed into intracellular calcium influx through NMDA receptors and L-type voltage sensitive calcium channels. For the transcription of c-fos, neural activity should be strong enough to activate mitogen-activated protein kinase (MAPK) signaling pathway which shows low calcium sensitivity. Upon translation, the auto-inhibition by Fos protein regulates basal Fos expression. The pattern of external stimuli and the valence of the stimulus to the animal change Fos signal, thus the signal reflects learning and memory aspects. Understanding the features of multiple components regulating Fos signaling is necessary for the optimal generation and interpretation of Fos signal.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.108-118
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• 2002

Objective : Acupuncture and herbal medicine have been used to prevent and treat cerebrovascular accident, such as stroke, and many studies of acupuncture and moxibustion concerning stroke have been undertaken in humans and various animals. However, the protective effect of the electroacupuncture (EA) of Huan-do (GB30) on the transient forebrain ischemia injury has not been published. Methods : The nenroprotective effects of EA (2 ms, 10 Hz, and 1 - 2 mA) of GB30 on the transient forebrain ischemia injury were investigated by immunohistochemistry of c-Fos-like protein in Sprague-Dawley rats. Results : The transient forebrain ischemia injury resulted in increased expression of c-Fos-like protein (cFL) in the dentate gyms (DG) and CAl for 6 hrs after ischemia, and EA increased significantly expression of cFL in the CAl and DG. For 48 hrs after, there was delayed expression of cFL at the CAl and DG, representing the sign of neuronal cell death, but EA decreased the delayed expression of cFL, significantly. Conclusion : These results suggest that the nenroprotective effects of EA on transient forebrain ischemia injury may be related to excitatory regulation of cFL at the early stage and inhibitory regulation in the long term.

• Journal of Life Science
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• v.24 no.10
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• pp.1055-1062
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• 2014

We investigated the expression of cucumber genes involved in lipid mobilization and metabolism during cotyledon development to compare gene activity and to study the direction of carbon (acetyl unit) transport between glyoxysomes and mitochondria. The core metabolic pathway involving 10 genes was examined in four intracellular compartments: glyoxysomes (peroxisomes), mitochondria, chloroplasts, and cytosol. Additionally, we tested the early germination response of dark-grown seedlings and the immediate light response for a further 3 days. According to the reverse transcription polymerase chain reaction (RT-PCR), 3-L-ketoacyl-CoA thiolase 2 (Thio2), isocitrate lyase (ICL), and malate synthase (MS), the genes involved in storage lipid mobilization showed a similar and consistent pattern of gene expression in seedling development. Furthermore, coordinate expression of the A BOUT DE SOUFFLE (BOU) gene with ICL and MS during seedling emergence pointed to a possible secondary route of acetyl unit (acetyl-CoA) transport between peroxisomes and mitochondria in cucumber. The expression of the BOU gene was light dependent, as shown by BOU activity in Arabidopsis, suggesting that the dark condition also results in weak membrane biogenesis. In addition, several genes were active throughout the development of the green cotyledon, even during senescence. In conclusion, this study summarizes oil-seed germination and gene expression during cucumber cotyledon development and proposes an additional route for acetyl unit transport.

• Toxicological Research
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• v.17
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• pp.59-69
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• 2001

Arsenic exposure is associated with several human diseases, including cancers, atherosclerosis, hypertension, and cerebrovascular diseases. In cultured cells, arsenite, an inorganic arsenic com-pound, was demonstrated to interfere with many physiological functions, such as enhancement of oxidative stress, delay of cell cycle progression, and induction of structural and numerical changes of chromosomes. The objective of this study is to investigate the effects of arsenic exposure on gene expression profiles by colorimetric cDNA microarray technique. HFW (normal human diploid skin fibroblasts), CL3 (human lung adenocarcinoma cell line), and HaCaT (immortalized human keratinocyte cell line) were treated with 5 $\mu\textrm{M}$ or 10 $\mu\textrm{M}$ sodium arsenite for 6 or 16 h, respectively. By a dual-color detection system, the expression profile of arsenite-treated cultures was compared to that of control cultures. Several genes expressed differentially were identified on the microarray membranes. For example, MDM2, SWI/SNF, ubiquitin specific protease 4, MAP3K11, RecQ protein-like 5, and Ribosomal protein Ll0a were consistently induced in all three cell types by arsenite, whereas prohibitin, cyclin D1, nucleolar protein 1, PCNA, Nm23, and immediate early protein (ETR101) were apparently inhibited. The present results suggest that arsenite insults altered the expression of several genes participating in cellular responses to DNA damage, stress, transcription, and cell cycle arrest.

• BMB Reports
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• v.44 no.7
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• pp.452-457
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• 2011

The Egr-1 is an immediate early response gene encoding a transcription factor that functions in the regulation of cell growth, differentiation, and apoptosis. Estrogen has diverse physiological effects, including cellular proliferation and neuroprotection against brain injury. There are two types of estrogen receptors (ERs), $ER{\alpha}$ and $ER{\beta}$. $ER{\alpha}$-induced Egr-1 expression has been extensively studied; however, the role of $ER{\beta}$ is yet not known. In the present study, we investigated whether or not $ER{\beta}$ induces Egr-1 expression in C6 rat glioma cells, which express $ER{\beta}$ but not $ER{\alpha}$. Our results show that $ER{\beta}$ promoted up-regulation of Egr-1 expression via a non-genomic mechanism involving the Raf/MEK1/Erk/Elk-1 signaling cascade.

• The Journal of Korean Physical Therapy
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• v.15 no.4
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• pp.190-198
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• 2003

Expression of c-fos, an immediate early gene, has accepted to be a marker of functional activity in neurons. This study was aimed to investigate the effects of cold therapy on the expression of spinal cord c-fos in rats of carrageenan-induced muscle pain. Muscle pain was induced in male Sprague-Dawley rats by intra-muscular injection of gastrocnemius with $2\%$ carrageenan. The paw withdrawal latency (PWL) and tail flick test (TFT) responses to heat stimuli were used to detect secondary hyperalgesia produced by the muscle pain and measured to assess the effects of cold. The expression of c-fos was determined in the lumbar regions of the spinal cord by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry assays. The secondary hyperalgesia to heat simuli (PWL and TFT) were significantly reduced in cold therapy compared with that in the controls. In RT-PCR assays the expression of c-fos mRNA was down-regulated in the lumbar spinal cord in cold group. In addition, Fos immunoreactivity in the dorsal horn of the lumbar spinal cord was decreased in cold group. These results suggested that application of cold attributed to increase PWL and TFT responses and to decrease expression of the c-fos produced by muscle pain.