Differential Transcription and Translation of Immediate Early Genes in the Gerbil Hippocampus after Transient Global Ischemia

Excitotoxic activation of glutamate receptors is thought to be a key event for the molecular pathogenesis of postischemic delayed neuronal death of CA-1 neurons in the gerbil hippocampus. Glutamate receptor stimulation also causes induction of transcription factors that belong to the class of immediate early genes. We examined the expression of six different immediate early genes in the gerbil hippocampus after transient global ischemia. Comparative analysis of c-fos and Krox-24 expression was carried out in the same animals at the transcriptional and translational level by in situ hybridization and immunocytochemistry. Postischemic synthesis of four additional immediate early gene (IEG)–encoded proteins (FOS-B, c-JUN, JUN-B, and JUN-D) was investigated by immunocytochemistry at recirculation intervals between 1 and 48 h. After 5 min of ischemia, transcription of c-fos and Krox-24 mRNA was induced in all hippocampal subpopulations with peak expression at 1 h after recirculation. In vulnerable CA-1 neurons, increased transcription of c-fos and Krox-24 was not followed by translation into protein. Induction of immediate early gene-encoded proteins was restricted to neuronal populations less vulnerable to brief ischemia and identified neurons that are targets of glutamate receptor-mediated neurotoxicity but that are destined to survive. Our data indicate an asynchronous synthesis and persistence of individual IEG-encoded proteins in these neurons. The staggered induction implies that combinatorial changes of transcription factors allow a differential postischemic regulation of target gene expression both spatially and over time.

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A novel 7-nucleotide motif located in 3' untranslated sequences of the immediate-early gene set mediates platelet-derived growth factor induction of the JE gene.

Molecular and Cellular Biology ◽

10.1128/mcb.12.12.5288 ◽

1992 ◽

Vol 12 (12) ◽

pp. 5288-5300 ◽

Cited By ~ 55

Author(s):

R R Freter ◽

J C Irminger ◽

J A Porter ◽

S D Jones ◽

C D Stiles

Keyword(s):

Growth Factor ◽

Immediate Early Genes ◽

Immediate Early Gene ◽

Early Gene ◽

Platelet Derived Growth Factor ◽

Immediate Early ◽

Control Element ◽

Gene Set ◽

Cis Acting ◽

Early Genes

A cohort of the serum and growth factor regulated immediate-early gene set is induced with slower kinetics than c-fos. Two of the first immediate-early genes characterized as such, c-myc and JE, are contained within this subset. cis-acting genomic elements mediating induction of the slower responding subset of immediate-early genes have never been characterized. Herein we characterize two widely separated genomic elements which are together essential for induction of the murine JE gene by platelet-derived growth factor, serum, interleukin-1, and double-stranded RNA. One of these elements is novel in several regards. It is a 7-mer, TTTTGTA, found in the proximal 3' sequences downstream of the JE stop codon. The 3' element is position dependent and orientation independent. It does not function in polyadenylation, splicing, or destabilization of the JE transcript. Copies of the 7-mer or its inverse are found at comparable 3' sites in 25 immediate-early genes that encode transcription factors or cytokines. Given its general occurrence, the 7-mer may be a required cis-acting control element mediating induction of the immediate-early gene set.

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LINC00473 as an Immediate Early Gene under the Control of the EGR1 Transcription Factor

Non-Coding RNA ◽

10.3390/ncrna6040046 ◽

2020 ◽

Vol 6 (4) ◽

pp. 46

Author(s):

Vincenza Aliperti ◽

Emilia Vitale ◽

Francesco Aniello ◽

Aldo Donizetti

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Immediate Early Genes ◽

Immediate Early Gene ◽

Early Gene ◽

Immediate Early ◽

Secondary Response ◽

Early Genes ◽

Regulatory Cascade ◽

Non Coding Rnas

Immediate early genes play an essential role in cellular responses to different stimuli. Many of them are transcription factors that regulate the secondary response gene expression. Non-coding RNAs may also be involved in this regulatory cascade. In fact, they are emerging as key actors of gene expression regulation, and evidence suggests that their dysregulation may underly pathological states. We previously took a snapshot of both coding and long non-coding RNAs differentially expressed in neuronal cells after brain-derived neurotrophic factor stimulation. Among these, the transcription factor EGR1 (a well-known immediate early gene) and LINC00473 (a primate-specific long non-coding RNA) that has emerged as an interesting RNA candidate involved in neuronal function and in cancer. In this work, we demonstrated that LINC00473 gene expression kinetics resembled that of immediate early genes in SH-SY5Y and HEK293T cells under different cell stimulation conditions. Moreover, we showed that the expression of LINC00473 is under the control of the transcription factor EGR1, providing evidence for an interesting functional relationship in neuron function.

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Engineering combinatorial and dynamic decoders using synthetic immediate-early genes

10.1101/2019.12.17.880179 ◽

2019 ◽

Author(s):

Pavithran T. Ravindran ◽

Maxwell Z. Wilson ◽

Siddhartha G. Jena ◽

Jared E. Toettcher

Keyword(s):

Growth Factor ◽

Signaling Pathways ◽

Intracellular Signaling ◽

Target Genes ◽

Immediate Early Genes ◽

Immediate Early Gene ◽

Early Gene ◽

Immediate Early ◽

Specific Target ◽

Early Genes

AbstractFor tissues to grow and function properly, cells must coordinate actions such as proliferation, differentiation and apoptosis. This coordination is achieved in part by the activation of intracellular signaling pathways that trigger the expression of context-specific target genes. While the function of these natural circuits has been actively studied, synthetic biology provides additional powerful tools for deconstructing, repurposing, and designing novel signal-decoding circuits. Here we report the construction of synthetic immediate-early genes (synIEGs), target genes of the Erk signaling pathway that implement complex, user-defined regulation and can be monitored through the use of live-cell biosensors to track transcription and translation. We demonstrate the power and flexibility of this approach by confirming Erk duration-sensing by the FOS immediate-early gene, elucidating how the BTG2 gene is regulated by transcriptional activation and translational repression after growth-factor stimulation, and by designing a synthetic immediate-early gene that responds with AND-gate logic to the combined presence of growth factor and DNA damage stimuli. Our work paves the way to defining the molecular circuits that link signaling pathways to specific target genes, highlighting an important role for post-transcriptional regulation in signal decoding that may be masked by analyses of RNA abundance alone.

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A novel 7-nucleotide motif located in 3' untranslated sequences of the immediate-early gene set mediates platelet-derived growth factor induction of the JE gene

Molecular and Cellular Biology ◽

10.1128/mcb.12.12.5288-5300.1992 ◽

1992 ◽

Vol 12 (12) ◽

pp. 5288-5300

Author(s):

R R Freter ◽

J C Irminger ◽

J A Porter ◽

S D Jones ◽

C D Stiles

Keyword(s):

Growth Factor ◽

Immediate Early Genes ◽

Immediate Early Gene ◽

Early Gene ◽

Platelet Derived Growth Factor ◽

Immediate Early ◽

Control Element ◽

Gene Set ◽

Cis Acting ◽

Early Genes

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Global Ischemia Induces Immediate-Early Genes Encoding Zinc Finger Transcription Factors

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-199607000-00005 ◽

1996 ◽

Vol 16 (4) ◽

pp. 557-565 ◽

Cited By ~ 57

Author(s):

Jari Honkaniemi ◽

Frank R. Sharp

Keyword(s):

Transcription Factors ◽

Dentate Gyrus ◽

Neuronal Death ◽

Immediate Early Genes ◽

Global Ischemia ◽

Immediate Early ◽

Mrna Levels ◽

Brain Areas ◽

Ca1 Neurons ◽

Early Genes

Ischemia induces immediate-early genes (IEGs) in brain. Since prolonged expression of some IEGs may precede neuronal death, some researchers have suggested that these IEGs mediate neuronal death. We therefore examined the effect of 5 and 10 min of global ischemia on the expression of the IEGs NGFI-A, NGFI-B, NGFI-C, egr-2, egr-3, and Nurr1 in gerbil brain. All of the IEGs were induced after 30 min of reperfusion in the hippocampus. Most of them were induced in several other regions as well, including cortex, hypothalamus, thalamus, and amygdala. The acute IEG induction decreased in most brain areas by 2–6 h. However, at 24 h following 5 min of ischemia NGFI-A continued to be expressed in the CA1 region and dentate gyrus. In the dentate gyrus, NGFI-C continued to be expressed for 24 h and egr-3 for as long as 72 h. In other brain areas, all of the IEGs returned to control levels by 72 h except in CA1, where most messenger RNA (mRNA) levels were decreased; this decrease correlated with marked neuronal loss. The persistent expression of NGFI-A in CA1 neurons destined to die and the persistent expression of NGFI-A, NGFI-C, and egr-3 genes in dentate granule cell neurons that survive may indicate that some transcription factors modulate cell death whereas others support cell survival when expressed for prolonged periods. The protein products of several transcription factors, including c- fos, are known to downregulate their own expression. The persistent expression of NGFI-A in the CA1 neurons destined to die could therefore be due to ischemia-induced transcriptional activation caused by, e.g., increased intracellular calcium levels plus a lack of negative feedback caused by the blockade of the translation of NGFI-A mRNA into protein.

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Immediate early genes and inducible transcription factors in mapping of the central nervous system function and dysfunction

10.1016/s0924-8196(02)x8010-5 ◽

2002 ◽

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Transcription Factors ◽

Immediate Early Genes ◽

Immediate Early ◽

System Function ◽

Central Nervous System Function ◽

Early Genes ◽

The Central Nervous System ◽

Nervous System Function

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Activation of immediate-early, early, and late promoters by temperature-sensitive and wild-type forms of herpes simplex virus type 1 protein ICP4

Molecular and Cellular Biology ◽

10.1128/mcb.5.8.1997-2008.1985 ◽

1985 ◽

Vol 5 (8) ◽

pp. 1997-2008 ◽

Cited By ~ 4

Author(s):

N A DeLuca ◽

P A Schaffer

Keyword(s):

Gene Expression ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Immediate Early Genes ◽

Early Gene ◽

Immediate Early ◽

Temperature Sensitive ◽

Wild Type ◽

Early Genes ◽

Simplex Virus

To better define the activities on herpes simplex virus type 1 gene expression of temperature-sensitive and wild-type forms of the transcriptional regulatory protein ICP4, regulatory sequences from immediate-early, early, and late herpes simplex virus genes were fused to the gene for chloramphenicol acetyltransferase (CAT). These constructs were used in trans induction and cotransfection experiments with wild-type and temperature-sensitive mutant alleles of ICP4. The ICP4 genes used in this study were cloned from the KOS strain (wild type) and two phenotypically distinct temperature-sensitive ICP4 mutants, tsB32 and tsL14 (DeLuca et al., J. Virol. 52:767-776, 1984), both alone and in conjunction with three other immediate-early genes. The latter series of plasmids was used to assess the influence of additional immediate-early gene products on gene expression in the presence of a given ICP4 allele. The results of this study demonstrate that the phenotypes of these ICP4 mutants observed in cell culture at the nonpermissive temperature were determined in part by activities associated with the mutant ICP4 polypeptides and that these activities differed from those of wild-type ICP4. Low levels of wild-type ICP4 had a marginal but reproducible stimulatory effect on immediate-early CAT gene expression, especially the pIE4/5CAT chimera. This effect was diminished with increasing quantities of ICP4, suggesting an inhibitory role for the wild-type form of the protein. The ICP4 mutants had a strong stimulatory effect on immediate-early CAT expression, consistent with their phenotypes at 39 degrees C. The mutant forms of the ICP4 polypeptide differed in their ability to induce CAT activity from an early chimeric gene. Thus, the tsL14 form of ICP4 was effective in early gene induction (i.e., ptkCAT was induced), whereas the ICP4 derived from tsB32 was slightly inhibitory. Cotransfection of tsB32 ICP4 simultaneously with other immediate-early genes resulted in a marginal increase in ptkCAT induction. This induction was enhanced when the gene for ICP4 was inactivated by restriction enzyme cleavage, substantiating the inhibitory effect of the tsB32 form of ICP4. The two mutant ICP4 genes (tsB32 and tsL14) were unable to trans-activate either of the late CAT constructs (p5CAT and pL42CAT) tested. Cotransfecting tsL14 ICP4 with the other immediate-early genes resulted in activation of p5CAT but not pL42CAT. Taken together, these studies demonstrate that (i) low levels of wild-type ICP4 have stimulatory effect on immediate-early promoters and that higher concentrations of wild-type ICP4 have an inhibitory effect on these promoters, (ii) isolated mutant form of ICP4 exhibit activities that reflect the phenotypes of the mutants from which they were isolated, and (iii) immediate-early gene products other than ICP4 are involved in determining the distinct phenotypes of the two mutants at 39 degrees Celsius.

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