No abstract available.
Animals ; Gene Expression* ; Genes, Immediate-Early* ; Rats*

OBJECTIVETo screen the learning and memory mutant from N-ethyl-N-nitrosourea (ENU) mutagenic zebrafish F1, and to get the new model animal to study the mechanism of learning and memory.

METHODSZebrafish mutant was screened by inhibitory avoidance behavioral test and identified by the expression of gene c-fos with qRT-PCR.

RESULTSWe isolated a zebrafish mutant related to learning and memory, fgt. In this fgt zebrafish mutant long-term memory was much lower than that in wild-type when tested at 24 h after training. The 24 h long-term memory in about half of fgt mutant F2 (13/30) were significantly lower than those in wild-type, and the others relatively normal. Compared with the expression in wild-type fishes, the expression of immediate-early genes (IEGs) c-fos in half of fgt mutant F2 (13/30) after exploring in a novel environment increased distinctly from the basal control levels statistically, and the others relatively normal, which were in accordance with the behavioral results.

CONCLUSIONThe zebrafish mutant fgt is a dominant mutant with defect in long-term memory.

Animals ; Disease Models, Animal ; Female ; Genes, Immediate-Early ; Genetic Testing ; Male ; Memory, Long-Term ; Zebrafish ; genetics

OBJECTIVETo investigate the effect of RNA interference targeting human cytomegalovirus immediate early gene 1 (HCMV- IE1) on the gene expression in vitro.

METHODSAccording to the sequence of HCMV-IE1 gene, the small interfering RNA (siRNA) sequences were designed and introduced into the eukaryotic expression vector containing the U6 promoter. After verification by sequence analysis, the recombinant eukaryotic plasmid (pHCMV-IE1i) was transfected into HEL HCMVAD169 cells. The effectiveness of HCMV-IE1 gene silencing was investigated by fluorescence microscopy, flow cytometry and RT-PCR.

RESULTSSequence analysis confirmed successful construction of the recombinant eukaryotic expression plasmid pHCMV-IE1i. The expression of HCMV-IE1 was effectively suppressed by pHCMV-IE1i transfection in HEL cells as shown by fluorescence microscopy, flow cytometry (P < 0.05) and RT-PCR (P < 0.05).

CONCLUSIONThe expression of HCMV-IE1 can be effectively suppressed by RNA interference technique in vitro, which provides experimental data for prevention and treatment of HCMV infection.

Antigens, Viral ; biosynthesis ; genetics ; Cell Line ; Genes, Immediate-Early ; Genetic Vectors ; genetics ; Humans ; Immediate-Early Proteins ; biosynthesis ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics ; Recombinant Proteins ; biosynthesis ; genetics

Previous studies have indicated that hyperthermic modulation in the delayed postischemic period, even when occurring days after an ischemic insult, may augment ischemic injury. In order to evaluate the molecular mechanisms of the detrimental effects of hyperthermia on ischemic outcome, we performed a study to assess the effects of delayed postischemic hyperthermia on the regional expression of message for the immediate early genes c-fos and c-jun. 60 minutes of transient middle cerebral artery occlusion was produced in rats by insertion of an intraluminal filament. 24 hours after reperfusion, rats which were awake were subjected to normothermic(37-38degreesC) or hyperthermic(40degreesC) temperature modulation for 3 hours in a heating chamber. Either 2 or 24 hours after temperature modulation, brains were examined for mRNA expression of c-fos and c-jun by the dot blot method. Four regions of interest were chosen: fronto-cingulate, sensorimotor, piriform-insular cortex, and caudoputamen. Dot blot analysis revealed that c-fos mRNA at 2 hours after temperature modulation was significantly upregulated in the ipsilateral fronto-cingulate cortex-the site of the ischemic penumbra- in rats exposed to ischemia+delayed hyperthermia, in comparison to rats exposed to sham+normothermia(one-way ANOVA with post-hoc Bonferroni's test, p<0.05). In contrast, c-jun mRNA was significantly upregulated by ischemia+delayed hyperthermia within regions of core ischemia-i.e., sensorimotor and piriform-insular cortex, and caudoputamen. These findings have extended those of our earlier histopathological study10) to show that a significant increase in c-fos or c-jun expression may be closely linked to cellular survival or death after delayed moderate hyperthermia following ischemia.
Animals ; Brain* ; Fever* ; Genes, Immediate-Early* ; Heating ; Hot Temperature ; Infarction, Middle Cerebral Artery ; Ischemia ; Rats* ; Reperfusion ; RNA, Messenger*

PURPOSE: Immaure brain is more resistant to seizure-induced neuronal damage than the adult brain in animal study. Immediate early genes such as c-jun play a critical role in neuronal damage. Therefore, we hypothesized that the difference of constitutive and electrically stimulated c-Jun expression would explain the difference in neuronal damage from seizures between immature and mature explant culture. METHODS: Seven and 14 days-in-vitro(DIV) hippocampal explant cultures derived from 8-day-old rat pups were used. Extracellular field recording was done in cultures. A 1-sec stimulus train(60 Hz, 0.1 msec rectangular pulses) was applied to the Schaffer collaterals, and the afterdischarge was recorded in CA1 pyramidal layer. Cultures were returned to the incubator and observed serially. Intensity of propidium iodide fluorescence indicative of neuronal damage was quantitated as percent of total damage induced by 2 mM NMDA. Proteins extracted from individual cultures were analyzed by Western blot. RESULTS: Constitutive c-Jun protein expression at 7 DIV was higher than that at 14 DIV. There was not a significant difference of c-Jun expression between the 7 DIV and 14 DIV cultures after electrical stimulation. Neuronal damage after electrical stimulation in the hippocampus at 7 DIV was significantly lower than at 14 DIV. CONCLUSION: The results show reduced neuronal injury from seizures in more immature culture. However, constitutive expression of c-Jun protein was higher. Higher constitutive expression may inhibit further induction of c-Jun from seizures and thus result in less severe neuronal injury.
Adult ; Animals ; Blotting, Western ; Brain ; Electric Stimulation ; Fluorescence ; Genes, Immediate-Early ; Hippocampus ; Humans ; Incubators ; N-Methylaspartate ; Neurons* ; Propidium ; Rats* ; Seizures

The hypothalamic suprachiasmatic nucleus (SCN) of the mammal is the circadian pacemaker responsible for generation of circadian rhythms. Several immediate-early genes are expressed in the SCN by light stimuli which induce phase shifts of animal activity rhythms. By using differential display-polymerase chain reaction, we investigated expression of several immediate-early genes in the light-stimulated SCN. In addition, we analyzed the light-induced expression changes of two known immediate-early genes, Arc and Rheb, in the SCN. We have screened and cloned 25 differentially expressed genes in the SCN, and identified a gene, a rat homologue of A6 kinase, which expression was regulated by light stimuli. One hour light stimuli during the subjective night dramatically induced the gene expression in the SCN, whereas light stimuli during the subjective light phase did not. This finding implies that a rat homolgue of A6 kinase may be involved in the photic entrainment of the circadian clock. On the other hand, Arc and Rheb mRNA expressions were not increased in the SCN by light stimuli.
Animals ; Circadian Clocks ; Circadian Rhythm ; Clone Cells ; Gene Expression ; Genes, Immediate-Early* ; Genes, vif ; Hand ; In Situ Hybridization ; Mammals ; Phosphotransferases ; Rats* ; RNA, Messenger ; Suprachiasmatic Nucleus*

OBJECTIVEThe effect of allitridin on the transcription levels of immediate-early (ie), early(e) and late (1) genes of human cytomegalovirus (HCMV) was investigated in order to explore the mechanism of allitridin against HCMV.

METHODEstablished the models of HCMV AD169 strain infected cells and AD169 strain infected cells treated with allitridin (9.6 mg x L(-1)), and they were compared with the appropriate dose(2.3 mg x L(-1)) of ganciclovir (GCV). All groups of cells were infected at 2.5 multiplicity of infection (MOI), using SYBR Green real-time PCR method to detect the dynamic change of ul122, ul123, ul54 and ul83 mRNA expression at 0.5, 2, 4, 6, 12, 24 h post-infection.

RESULTThe mRNA levels of ul122 and ul123 in AD169 infected cells treated with allitridin at all time points were markedly lower than those of AD169 infected controls (P<0.05), but there were no significant difference of ul122 gene in AD169 infected cells treated with GCV and AD169 infected cells at 0.5-6 h post-infection. The inhibitory rates of allitridin to AD169 ul122 and ul123 mRNA reached 75.2% and 70.4% at 24 h post-infection, respectively. The expression of ul54 mRNA in two drug-treatment groups at all time points were lower than those of AD169 infected cells group (P<0.05). The inhibitory rates of alltridin and GCV to AD169 ul54 mRNA were 45.4% and 27.2% at 24 h post-infection,respectively. The expression of HCMV ul83 mRNA in all groups rapidly increased after 6 h of infection,which is most obvious in AD169 infected cells group. The inhibitory rates of alltridin and GCV to AD169 ul83 mRNA were 45.9% and 26.2% at 24 h post-infection, respectively.

CONCLUSIONAllitridin could effectively suppress the transcription of ie genes (ul122 and ul123) of HCMV AD169 strain, led the expression of mRNA significantly lowerd. It was able to supress the transcription of egene (ul54) and l gene (ul83) too, indicating that HCMV ie genes may be the key target of allitridin against HCMV.

Allyl Compounds ; pharmacology ; Antiviral Agents ; pharmacology ; Cell Line ; Cytomegalovirus ; drug effects ; genetics ; Genes, Immediate-Early ; genetics ; Genes, Viral ; genetics ; Humans ; Sulfides ; pharmacology ; Transcription, Genetic ; drug effects

BACKGROUND: Anterior cerebellar artery (AICA) occlusion results in vestibular dysfunctions because the AICA supplies the vestibular nuclei (VN) in the brain stem as well as the peripheral vestibular organs in the inner ear. The purpose of this study was to evaluate the expression of immediate-early gene products, a metabolic marker of neural excitation in neurons, by AICA occlusion in the VN of Sprague-Dawley rats. METHODS: After chloral hydrate anesthesia all animals were subjected to unilateral AICA occlusion by using a microsurgical clamp for 30 min to induce a transient ischemia. Unilateral labyrinthectomy was chemically undertaken to eliminate vestibular afferent activity. Immunohistochemical staining and image analysis for cFos, FosB, Krox-24, and JunB proteins were performed 2 hours after AICA occlusion. RESULTS: There was a high expression of cFos protein in the bilateral medial and inferior VN 2 hours after AICA occlusion. AICA occlusion induced minimal changes in cFos protein expression in the lateral and superior VN. Mild to moderate expressions of FosB and JunB protein in VN was observed 2 hours after ischemic injury of the brain stem and inner ear. On the contrary, the number of cFos and FosB immunoreactive neurons significantly decreased in the medial vestibular nucleus ipsilateral to the injured labyrinth 2 hours after AICA occlusion in the UL group. CONCLUSIONS: These results suggest that ischemic afferent activity from the peripheral vestibular apparatus is essential for the expression of immediate-early gene products in the medial and inferior VN of rats following AICA occlusion.
Anesthesia ; Animals ; Arteries* ; Brain Stem ; Chloral Hydrate ; Ear, Inner ; Equipment and Supplies ; Genes, Immediate-Early* ; Ischemia ; Neurons ; Rats ; Rats, Sprague-Dawley* ; Vestibular Nuclei* ; Vestibule, Labyrinth

OBJECTIVES: In order to investigate the maturational process of intracellular signal transduction system in rat brain, we studied the induction of the immediate early genes(IEGs)c-fos, junB, and TIS1 in each developmental stage after kainic acid(KA)induced seizure in young rat hippocampus and then compared these with the results after electroconvulsive shock(ECS) And to elucidate the induction mechanism of c-fos via mitogen-activated protein kinase(MAPK)by KA in each developmental stage, we investigated the phosphorylation of p42, p44 MAPK and Elk-1 after KA treatment in young rat hippocampus. METHODS: We examined the induction patterns of IEGs by northern blot analysis, and the phosphorylation of p42, p44 MAPK and Elk-1 by immunoblotting in rat hippocampus at post-natal day 7, 14, and 21(P7, P14 & P21) respectively after intraperitoneal injection of KA. RESULTS: Unlike ECS, KA did not induce c-fos, junB, and TIS1 in P7 hippocampus. But these genes were apparently induced at P14 and to an adult level at P21. These three IEGs showed similar temporal patterns of induction in each developmental stage. Although the basal level of phosphorylated 42p, 44p MAPK was considerable in P7 rat hippocampus, the increase of phosphorylation after KA treatment was observed at P14 . While the phosphorylation of Elk-1 was detected with high basal level in P7 rat, the amount of phosphorylated Elk-1 was not changed after KA treatment. CONCLUSION: Our results suggest that the differences in IEGs induction patterns between KA and ECS may be due to the differences in the activated signal transduction pathways. And our results also implicate that the signal transduction system involved in MAPK phosphorylation after KA treatment mature with aging and c-fos induction via MAPK activation may be regulated through some pathways other than Elk-1 in rat hippocampus.
Adult ; Aging ; Animals ; Blotting, Northern ; Brain ; Genes, Immediate-Early* ; Hippocampus* ; Humans ; Immunoblotting ; Injections, Intraperitoneal ; Kainic Acid* ; Mitogen-Activated Protein Kinase 3* ; Phosphorylation* ; Rats* ; Seizures ; Signal Transduction

The expression of the c-fos and krox-24 (immediate early genes: IEGs) and the BDNF (late response gene) were investigated by convulsants such as kainate (KA, 200 micrometer), N-methyl-D-aspartate (NMDA, 10 mM), glutamate (GLU, 2 mM), and picrotoxin (PTX, 20 micrometer in the rat C6 glioma cells. In addition, the changes of their expression patterns were investigated by the anticonvulsants such as a NMDA antagonist MK-801, phenytoin, phenobarbiw, diazepam, and newer antiepileptic drugs like felbamate and gabapentin. NMDA induced c-fos and krox-24 expromiom were decreased spatially by the anticonvulsants. KA, NMDA, GLU, and PTX-induced BDNF expression were increased by the anticonvulsants. These results imply the molecular basis of the anticonvulsant action mechanism lies in differential and coordinated transcriptional regulation of IEGs.
Animals ; Anticonvulsants* ; Brain-Derived Neurotrophic Factor ; Convulsants ; Diazepam ; Dizocilpine Maleate ; Genes, Immediate-Early* ; Glioma ; Glutamic Acid ; Kainic Acid ; N-Methylaspartate ; Phenytoin ; Picrotoxin ; Rats