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1.
Arch Virol ; 169(5): 116, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722402

RESUMO

In this study, we investigated the role of serum/glucocorticoid-regulated kinase 1 (SGK1) in varicella-zoster virus (VZV) replication. VZV DNA replication and plaque formation were inhibited by SGK1 knockout and treatment with an SGK1 inhibitor. Furthermore, SGK1 inhibition suppressed the increase in cyclin B1 expression induced by VZV infection. These results suggest that VZV infection induces SGK1 activation, which is required for efficient viral proliferation through the expression of cyclin B1. This is the first study to report that SGK1 is involved in the VZV life cycle.


Assuntos
Ciclina B1 , Herpesvirus Humano 3 , Proteínas Imediatamente Precoces , Proteínas Serina-Treonina Quinases , Replicação Viral , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Humanos , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ciclina B1/metabolismo , Ciclina B1/genética , Linhagem Celular , Replicação do DNA
2.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731543

RESUMO

Ribonuclease P (RNase P) complexed with an external guide sequence (EGS) represents a promising nucleic acid-based gene targeting approach for gene expression knock-down and modulation. The RNase P-EGS strategy is unique as an EGS can be designed to basepair any mRNA sequence and recruit intracellular RNase P for hydrolysis of the target mRNA. In this study, we provide the first direct evidence that the RNase P-based approach effectively blocks the gene expression and replication of herpes simplex virus 2 (HSV-2), the causative agent of genital herpes. We constructed EGSs to target the mRNA encoding HSV-2 single-stranded DNA binding protein ICP8, which is essential for viral DNA genome replication and growth. In HSV-2 infected cells expressing a functional EGS, ICP8 levels were reduced by 85%, and viral growth decreased by 3000 folds. On the contrary, ICP8 expression and viral growth exhibited no substantial differences between cells expressing no EGS and those expressing a disabled EGS with mutations precluding RNase P recognition. The anti-ICP8 EGS is specific in targeting ICP8 because it only affects ICP8 expression but does not affect the expression of the other viral immediate-early and early genes examined. This study shows the effective and specific anti-HSV-2 activity of the RNase P-EGS approach and demonstrates the potential of EGS RNAs for anti-HSV-2 applications.


Assuntos
Regulação Viral da Expressão Gênica , Herpesvirus Humano 2 , Replicação Viral , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/fisiologia , Humanos , Ribonuclease P/metabolismo , Ribonuclease P/genética , Animais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Chlorocebus aethiops , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Vero , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Proteínas de Ligação a DNA
3.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731826

RESUMO

Although Herpes simplex virus type 1 (HSV-1) has been deeply studied, significant gaps remain in the fundamental understanding of HSV-host interactions: our work focused on studying the Infected Cell Protein 27 (ICP27) as an inhibitor of the Absent-in-melanoma-2 (AIM 2) inflammasome pathway, leading to reduced pro-inflammatory cytokines that influence the activation of a protective innate immune response to infection. To assess the inhibition of the inflammasome by the ICP27, hTert-immortalized Retinal Pigment Epithelial cells (hTert-RPE 1) infected with HSV-1 wild type were compared to HSV-1 lacking functional ICP27 (HSV-1∆ICP27) infected cells. The activation of the inflammasome by HSV-1∆ICP27 was demonstrated by quantifying the gene and protein expression of the inflammasome constituents using real-time PCR and Western blot. The detection of the cleavage of the pro-caspase-1 into the active form was performed by using a bioluminescent assay, while the quantification of interleukins 1ß (IL-1ß) and 18 (IL-18)released in the supernatant was quantified using an ELISA assay. The data showed that the presence of the ICP27 expressed by HSV-1 induces, in contrast to HSV-1∆ICP27 vector, a significant downregulation of AIM 2 inflammasome constituent proteins and, consequently, the release of pro-inflammatory interleukins into the extracellular environment reducing an effective response in counteracting infection.


Assuntos
Citocinas , Herpesvirus Humano 1 , Proteínas Imediatamente Precoces , Inflamassomos , Epitélio Pigmentado da Retina , Humanos , Inflamassomos/metabolismo , Herpesvirus Humano 1/fisiologia , Citocinas/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Proteínas Imediatamente Precoces/genética , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/virologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Linhagem Celular , Herpes Simples/imunologia , Herpes Simples/metabolismo , Herpes Simples/virologia , Proteínas de Ligação a DNA
4.
Int J Mol Sci ; 25(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38673987

RESUMO

Sodium chloride (NaCl) activates Th17 and dendritic cells in hypertension by stimulating serum/glucocorticoid kinase 1 (SGK1), a sodium sensor. Memory T cells also play a role in hypertension by infiltrating target organs and releasing proinflammatory cytokines. We tested the hypothesis that the role of T cell SGK1 extends to memory T cells. We employed mice with a T cell deletion of SGK1, SGK1fl/fl × tgCD4cre mice, and used SGK1fl/fl mice as controls. We treated the mice with L-NAME (0.5 mg/mL) for 2 weeks and allowed a 2-week washout interval, followed by a 3-week high-salt (HS) diet (4% NaCl). L-NAME/HS significantly increased blood pressure and memory T cell accumulation in the kidneys and bone marrow of SGK1fl/fl mice compared to knockout mice on L-NAME/HS or groups on a normal diet (ND). SGK1fl/fl mice exhibited increased albuminuria, renal fibrosis, and interferon-γ levels after L-NAME/HS treatment. Myography demonstrated endothelial dysfunction in the mesenteric arterioles of SGK1fl/fl mice. Bone marrow memory T cells were adoptively transferred from either mouse strain after L-NAME/HS administration to recipient CD45.1 mice fed the HS diet for 3 weeks. Only the mice that received cells from SGK1fl/fl donors exhibited increased blood pressure and renal memory T cell infiltration. Our data suggest a new therapeutic target for decreasing hypertension-specific memory T cells and protecting against hypertension.


Assuntos
Hipertensão , Proteínas Imediatamente Precoces , NG-Nitroarginina Metil Éster , Proteínas Serina-Treonina Quinases , Cloreto de Sódio na Dieta , Animais , Masculino , Camundongos , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Hipertensão/patologia , Proteínas Imediatamente Precoces/metabolismo , Proteínas Imediatamente Precoces/genética , Rim/metabolismo , Rim/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , NG-Nitroarginina Metil Éster/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Cloreto de Sódio na Dieta/efeitos adversos , Linfócitos T/metabolismo , Linfócitos T/imunologia
5.
Antiviral Res ; 225: 105870, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556059

RESUMO

Following acute human alphaherpesvirus 1 (HSV-1) infection of oral-facial mucosal surfaces, sensory neurons in trigeminal ganglia (TG) are important sites for life-long latency. Neurons in the central nervous system, including brainstem, also harbor viral genomes during latency. Periodically, certain cellular stressors trigger reactivation from latency, which can lead to recurrent HSV-1 disease: herpes labialis, herpes stromal keratitis, and encephalitis for example. Activation of the glucocorticoid receptor (GR) by stressful stimuli enhances HSV-1 gene expression, replication, and explant-induced reactivation. GR and certain stress-induced Krüppel like factors (KLF) cooperatively transactivate cis-regulatory modules (CRM) that drive expression of viral transcriptional regulatory proteins (ICP0, ICP4, and ICP27). These CRMs lack GR response elements (GRE); however, specificity protein 1 (Sp1) binding sites are crucial for GR and KLF15 or KLF4 mediated transactivation. Hence, we tested whether Sp1 or Sp3 regulate viral replication and transactivation of the ICP0 promoter. During early stages of explant-induced reactivation from latency, the number of Sp3+ TG neurons were significantly higher relative to TG from latently infected mice. Conversely, Sp1+ TG neurons were only increased in females, but not male mice, during explant-induced reactivation. Sp1 siRNA significantly reduced HSV-1 replication in cultured mouse (Neuro-2A) and monkey (CV-1) cells. Mithramycin A, an antibiotic that has anti-tumor activity preferentially interacts with GC-rich DNA, including Sp1 binding sites, significantly reduced HSV-1 replication indicating it has antiviral activity. GR and Sp1 or Sp3 transactivated the HSV-1 ICP0 promoter in Neuro-2A and CV-1 cells confirming these transcription factors enhance viral replication and gene expression.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Proteínas Imediatamente Precoces , Plicamicina/análogos & derivados , Feminino , Humanos , Camundongos , Animais , Herpesvirus Humano 1/genética , Receptores de Glucocorticoides/metabolismo , Ativação Viral , Latência Viral/genética , Proteínas Imediatamente Precoces/genética , Antibacterianos , Ubiquitina-Proteína Ligases/genética
6.
Viral Immunol ; 37(2): 115-123, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38498796

RESUMO

Nasopharyngeal carcinoma (NPC) is a specific human malignancy with unique geographic distribution and genetic backgrounds. Although early treatment with radio-chemotherapy has been proven effective for NPC therapy, its therapeutic efficacy substantially diminishes in the late stages of this malignancy. In the tumor microenvironment of NPC, PD-L1 has been demonstrated as a critical factor in impairing T cell activation. As an etiological role for NPC development, it is found that Epstein-Barr virus (EBV) latent proteins upregulated PD-L1 expression. However, whether EBV lytic protein affects PD-L1 expression remains unclear. In this study, through monitoring the mRNA expression pattern of lytic genes and PD-L1 in EBV-positive NPC cell line NA, EBV immediately-early gene BRLF1(Rta) was found to have the potential for PD-L1 activation. Furthermore, we identified that Rta expression enhanced PD-L1 expression in mRNA and protein levels through quantitative real-time polymerase chain reaction and western blotting analysis. The luciferase reporter assay revealed that Rta expression enhanced PD-L1 promoter activity. We also demonstrated that Rta-induced PD-L1 expressions could impair interleukin 2 secretion of T cells, and this mechanism may be through ERK activation. These results displayed the importance of EBV Rta in PD-L1 expression in NPC and may give an alternative target for NPC therapy.


Assuntos
Infecções por Vírus Epstein-Barr , Proteínas Imediatamente Precoces , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Antígeno B7-H1/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , RNA Mensageiro/genética , Microambiente Tumoral , Transativadores/genética , Transativadores/metabolismo , Transativadores/farmacologia , Proteínas Imediatamente Precoces/genética
7.
J Virol ; 98(4): e0193523, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38451085

RESUMO

Placental infection plays a central role in the pathogenesis of congenital human cytomegalovirus (HCMV) infections and is a cause of fetal growth restriction and pregnancy loss. HCMV can replicate in some trophoblast cell types, but it remains unclear how the virus evades antiviral immunity in the placenta and how infection compromises placental development and function. Human trophoblast stem cells (TSCs) can be differentiated into extravillous trophoblasts (EVTs), syncytiotrophoblasts (STBs), and organoids, and this study assessed the utility of TSCs as a model of HCMV infection in the first-trimester placenta. HCMV was found to non-productively infect TSCs, EVTs, and STBs. Immunofluorescence assays and flow cytometry experiments further revealed that infected TSCs frequently only express immediate early viral gene products. Similarly, RNA sequencing found that viral gene expression in TSCs does not follow the kinetic patterns observed during lytic infection in fibroblasts. Canonical antiviral responses were largely not observed in HCMV-infected TSCs and TSC-derived trophoblasts. Rather, infection dysregulated factors involved in cell identity, differentiation, and Wingless/Integrated signaling. Thus, while HCMV does not replicate in TSCs, infection may perturb trophoblast differentiation in ways that could interfere with placental function. IMPORTANCE: Placental infection plays a central role in human cytomegalovirus (HCMV) pathogenesis during pregnancy, but the species specificity of HCMV and the limited availability and lifespan of primary trophoblasts have been persistent barriers to understanding how infection impacts this vital organ. Human trophoblast stem cells (TSCs) represent a new approach to modeling viral infection early in placental development. This study reveals that TSCs, like other stem cell types, restrict HCMV replication. However, infection perturbs the expression of genes involved in differentiation and cell fate determination, pointing to a mechanism by which HCMV could cause placental injury.


Assuntos
Citomegalovirus , Células-Tronco , Trofoblastos , Replicação Viral , Feminino , Humanos , Gravidez , Diferenciação Celular/genética , Linhagem da Célula/genética , Citomegalovirus/crescimento & desenvolvimento , Citomegalovirus/patogenicidade , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/fisiopatologia , Infecções por Citomegalovirus/virologia , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Placenta/citologia , Placenta/patologia , Placenta/fisiopatologia , Placenta/virologia , Primeiro Trimestre da Gravidez , Células-Tronco/citologia , Células-Tronco/virologia , Trofoblastos/citologia , Trofoblastos/virologia
8.
Am J Med Sci ; 367(6): 397-405, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38437946

RESUMO

BACKGROUND: Numerous studies have explored the therapeutic potential of microRNA (miR) in myocardial infarction (MI) treatment. This study focuses on the role of miR-322-5p in MI, particularly in its regulatory interaction with B-cell translocation gene 2 (BTG2). MATERIALS AND METHODS: Expression levels of miR-322-5p and BTG2 were assessed in a rat MI model. Adenovirus altering miR-322-5p or BTG2 expression were administered to MI rats. Evaluation included cardiac function, inflammation, myocardial injury, pathological changes, apoptosis, and NF-κB pathway-related genes in MI rats post-targeted treatment. The miR-322-5p and BTG2 targeting relationship was investigated. RESULTS: MI rats exhibited low miR-322-5p and high BTG2 expression in the myocardial tissues. Restoration of miR-322-5p enhanced cardiac function, alleviated inflammation and myocardial injury, mitigated pathological changes and apoptosis, and deactivated the NF-κB pathway in MI rats. BTG2 expression was negatively-regulated by miR-322-5p. Overexpressed BTG2 counteracted miR-322-5p-induced cardioprotection on MI rats. CONCLUSION: This study provides evidence that miR-322-5p protects against MI by suppressing BTG2 expression.


Assuntos
Proteínas Imediatamente Precoces , MicroRNAs , Infarto do Miocárdio , Ratos Sprague-Dawley , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Ratos , Masculino , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Apoptose , NF-kappa B/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Modelos Animais de Doenças
9.
Mol Biol Rep ; 51(1): 376, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427115

RESUMO

OBJECTIVE: Organisms and cellular viability are of paramount importance to living creatures. Disruption of the balance between cell survival and apoptosis results in compromised viability and even carcinogenesis. One molecule involved in keeping this homeostasis is serum-glucocorticoid regulated kinase (SGK) 1. Emerging evidence points to a significant role of SGK1 in cell growth and survival, cell metabolism, reproduction, and life span, particularly in prenatal programming and reproductive senescence by the same token. Whether the hormone inducible SGK1 kinase is a major driver in the pathophysiological processes of prenatal programming and reproductive senescence? METHOD: The PubMed/Medline, Web of Science, Embase/Ovid, and Elsevier Science Direct literature databases were searched for articles in English focusing on SGK1 published up to July 2023 RESULT: Emerging evidence is accumulating pointing to a pathophysiological role of the ubiquitously expressed SGK1 in the cellular and organismal viability. Under the regulation of specific hormones, extracellular stimuli, and various signals, SGK1 is involved in several biological processes relevant to viability, including cell proliferation and survival, cell migration and differentiation. In line, SGK1 contributes to the development of germ cells, embryos, and fetuses, whereas SGK1 inhibition leads to abnormal gametogenesis, embryo loss, and truncated reproductive lifespan. CONCLUTION: SGK1 integrates a broad spectrum of effects to maintain the homeostasis of cell survival and apoptosis, conferring viability to multiple cell types as well as both simple and complex organisms, and thus ensuring appropriate prenatal development and reproductive lifespan.


Assuntos
Glucocorticoides , Proteínas Imediatamente Precoces , Gravidez , Feminino , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Reprodução
10.
Viruses ; 16(2)2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38400065

RESUMO

Programmed necrosis is an integral part of intrinsic immunity, serving to combat invading pathogens and restricting viral dissemination. The orchestration of necroptosis relies on a precise interplay within the necrosome complex, which consists of RIPK1, RIPK3 and MLKL. Human cytomegalovirus (HCMV) has been found to counteract the execution of necroptosis during infection. In this study, we identify the immediate-early 1 (IE1) protein as a key antagonist of necroptosis during HCMV infection. Infection data obtained in a necroptosis-sensitive cell culture system revealed a robust regulation of post-translational modifications (PTMs) of the necrosome complex as well as the importance of IE1 expression for an effective counteraction of necroptosis. Interaction analyses unveiled an association of IE1 and RIPK3, which occurs in an RHIM-domain independent manner. We propose that this interaction manipulates the PTMs of RIPK3 by promoting its ubiquitination. Furthermore, IE1 was found to exert an indirect activity by modulating the levels of MLKL via antagonizing its interferon-mediated upregulation. Overall, we claim that IE1 performs a broad modulation of innate immune signaling to impede the execution of necroptotic cell death, thereby generating a favorable environment for efficient viral replication.


Assuntos
Citomegalovirus , Proteínas Imediatamente Precoces , Humanos , Citomegalovirus/fisiologia , Morte Celular/fisiologia , Apoptose/fisiologia , Necrose , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
11.
FASEB J ; 38(3): e23459, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38329343

RESUMO

Wound healing is facilitated by neoangiogenesis, a complex process that is essential to tissue repair in response to injury. MicroRNAs are small, noncoding RNAs that can regulate the wound healing process including stimulation of impaired angiogenesis that is associated with type-2 diabetes (T2D). Expression of miR-409-3p was significantly increased in the nonhealing skin wounds of patients with T2D compared to the non-wounded normal skin, and in the skin of a murine model with T2D. In response to high glucose, neutralization of miR-409-3p markedly improved EC growth and migration in human umbilical vein endothelial cells (HUVECs), promoted wound closure and angiogenesis as measured by increased CD31 in human skin organoids, while overexpression attenuated EC angiogenic responses. Bulk mRNA-Seq transcriptomic profiling revealed BTG2 as a target of miR-409-3p, where overexpression of miR-409-3p significantly decreased BTG2 mRNA and protein expression. A 3' untranslated region (3'-UTR) luciferase assay of BTG2 revealed decreased luciferase activity with overexpression of miR-409-3p, while inhibition had opposite effects. Mechanistically, in response to high glucose, miR-409-3p deficiency in ECs resulted in increased mTOR phosphorylation, meanwhile BTG-anti-proliferation factor 2 (BTG2) silencing significantly decreased mTOR phosphorylation. Endothelial-specific and tamoxifen-inducible miR-409-3p knockout mice (MiR-409IndECKO ) with hyperglycemia that underwent dorsal skin wounding showed significant improvement of wound closure, increased blood flow, granulation tissue thickness (GTT), and CD31 that correlated with increased BTG2 expression. Taken together, our results show that miR-409-3p is a critical mediator of impaired angiogenesis in diabetic skin wound healing.


Assuntos
Diabetes Mellitus Tipo 2 , Proteínas Imediatamente Precoces , MicroRNAs , Proteínas Supressoras de Tumor , Animais , Humanos , Camundongos , Angiogênese , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 2/genética , Glucose , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteínas Imediatamente Precoces/genética , Luciferases , Camundongos Obesos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro , Serina-Treonina Quinases TOR , Proteínas Supressoras de Tumor/genética , Cicatrização/genética
12.
mBio ; 15(3): e0347923, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349188

RESUMO

Productive replication of herpes simplex virus (HSV) relies upon a well-ordered transcriptional cascade flowing from immediate-early (IE) to early (E) to late (L) gene products. While several virus-encoded transcriptional activators are involved in this process, IE and E gene promoters also contain multiple binding sites for the ubiquitously expressed cellular transcription factor Sp1. Sp1 has been previously implicated in activating HSV-1 gene transcription downstream of these sites, but why Sp1-binding sites are maintained in the promoters of genes activated by virus-encoded activators remains unclear. We hypothesized that Sp1 enables continued HSV-1 transcription and replication when viral transactivators are limited. We used a depletion-based approach in human foreskin fibroblasts to investigate the specific contribution of Sp1 to the initiation and progression of the HSV-1 lytic gene cascade. We found that Sp1 increased viral transcript levels, protein expression, and replication following infection with VP16- or ICP0-deficient viruses but had little to no effect on rescued viruses or during wild-type (WT) HSV-1 infection. Moreover, Sp1 promoted WT virus transcription and replication following interferon treatment of fibroblasts and thus may contribute to viral immune evasion. Interestingly, we observed reduced expression of Sp1 and Sp1-family transcription factors in differentiated sensory neurons compared to undifferentiated cells, suggesting that reduced Sp1 levels may also contribute to HSV-1 latent infection. Overall, these findings indicate that Sp1 can promote HSV-1 gene expression in the absence of key viral transactivators; thus, HSV-1 may use Sp1 to maintain its gene expression and replication under adverse conditions.IMPORTANCEHerpes simplex virus (HSV) is a common human pathogen that actively replicates in the epithelia but can persist for the lifetime of the infected host via a stable, latent infection in neurons. A key feature of the HSV replication cycle is a complex transcriptional program in which virus and host-cell factors coordinate to regulate expression of the viral gene products necessary for continued viral replication. Multiple binding sites for the cellular transcription factor Sp1 are located in the promoters of HSV-1 genes, but how Sp1 binding contributes to transcription and replication of wild-type virus is not fully understood. In this study, we identified a specific role for Sp1 in maintaining HSV-1 gene transcription under adverse conditions, as when virus-encoded transcriptional activators were absent or limited. Preservation of Sp1-binding sites in HSV-1 gene promoters may thus benefit the virus as it navigates diverse cell types and host-cell conditions during infection.


Assuntos
Herpes Simples , Infecções por Herpesviridae , Herpesvirus Humano 1 , Proteínas Imediatamente Precoces , Infecção Latente , Humanos , Herpesvirus Humano 1/fisiologia , Transativadores/genética , Proteínas Imediatamente Precoces/genética , Fatores de Transcrição/metabolismo , Replicação Viral , Expressão Gênica , Regulação Viral da Expressão Gênica
13.
mBio ; 15(2): e0262123, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38165154

RESUMO

Human cytomegalovirus (HCMV) requires the robust expression of two immediate early proteins, IE1 and IE2, immediately upon infection to suppress the antiviral response and promote viral gene expression. While transcriptional control of IE1 and IE2 has been extensively studied, the role of post-transcriptional regulation of IE1 and IE2 expression is relatively unexplored. We previously found that the shared major immediate early 5' untranslated region (MIE 5' UTR) of the mature IE1 and IE2 transcripts plays a critical role in facilitating the translation of the IE1 and IE2 mRNAs. As RNA secondary structure in 5' UTRs can regulate mRNA translation efficiency, we used selective 2'-hydroxyl acylation analyzed by primer extension and mutational profiling (SHAPE-MaP) to identify RNA structures in the shared MIE 5' UTR. We found that the MIE 5' UTR contains three stable stem loop structures. Using a series of recombinant viruses to investigate the role of each stem loop in IE1 and IE2 protein synthesis, we found that the stem loop closest to the 5' end of the MIE 5' UTR (SL1) is both necessary and sufficient for efficient IE1 and IE2 mRNA translation and HCMV replication. The positive effect of SL1 on mRNA translation and virus replication was dependent on its location within the 5' UTR. Surprisingly, a synthetic stem loop with the same free energy as SL1 in its native location also supported wild type levels of IE1 and IE2 mRNA translation and virus replication, suggesting that the presence of RNA structure at a specific location in the 5' UTR, rather than the primary sequence of the RNA, is critical for efficient IE1 and IE2 protein synthesis. These data reveal a novel post-transcriptional regulatory mechanism controlling IE1 and IE2 expression and reinforce the critical role of RNA structure in regulating HCMV protein synthesis and replication.IMPORTANCEThese results reveal a new aspect of immediate early gene regulation controlled by non-coding RNA structures in viral mRNAs. Previous studies have largely focused on understanding viral gene expression at the level of transcriptional control. Our results show that a complete understanding of the control of viral gene expression must include an understanding of viral mRNA translation, which is driven in part by RNA structure(s) in the 5' UTR of viral mRNAs. Our results illustrate the importance of these additional layers of regulation by defining specific 5' UTR RNA structures regulating immediate early gene expression in the context of infection and identify important features of RNA structure that govern viral mRNA translation efficiency. These results may therefore broadly impact current thinking on how viral gene expression is regulated for human cytomegalovirus and other DNA viruses.


Assuntos
Citomegalovirus , Proteínas Imediatamente Precoces , Humanos , Regiões 5' não Traduzidas , Citomegalovirus/fisiologia , Proteínas Virais/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Replicação Viral , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
J Virol ; 98(2): e0138623, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38240593

RESUMO

The Kaposi's sarcoma-associated herpesvirus (KSHV) genome consists of an approximately 140-kb unique coding region flanked by 30-40 copies of a 0.8-kb terminal repeat (TR) sequence. A gene enhancer recruits transcription-related enzymes by having arrays of transcription factor binding sites. Here, we show that KSHV TR possesses transcription regulatory function with latency-associated nuclear antigen (LANA). Cleavage under targets and release using nuclease demonstrated that TR fragments were occupied by LANA-interacting histone-modifying enzymes in naturally infected cells. The TR was enriched with histone H3K27 acetylation (H3K27Ac) and H3K4 tri-methylation (H3K4me3) modifications and also expressed nascent RNAs. The sites of H3K27Ac and H3K4me3 modifications were also conserved in the KSHV unique region among naturally infected primary effusion lymphoma cells. KSHV origin of lytic replication (Ori-Lyt) showed similar protein and histone modification occupancies with that of TR. In the Ori-Lyt region, the LANA and LANA-interacting proteins colocalized with an H3K27Ac-modified nucleosome along with paused RNA polymerase II. The KSHV transactivator KSHV replication and transcription activator (K-Rta) recruitment sites franked the LANA-bound nucleosome, and reactivation evicted the LANA-bound nucleosome. Including TR fragments in reporter plasmid enhanced inducible viral gene promoter activities independent of the orientations. In the presence of TR in reporter plasmids, K-Rta transactivation was drastically increased, while LANA acquired the promoter repression function. KSHV TR, therefore, functions as an enhancer for KSHV inducible genes. However, in contrast to cellular enhancers bound by multiple transcription factors, perhaps the KSHV enhancer is predominantly regulated by the LANA nuclear body.IMPORTANCEEnhancers are a crucial regulator of differential gene expression programs. Enhancers are the cis-regulatory sequences determining target genes' spatiotemporal and quantitative expression. Here, we show that Kaposi's sarcoma-associated herpesvirus (KSHV) terminal repeats fulfill the enhancer definition for KSHV inducible gene promoters. The KSHV enhancer is occupied by latency-associated nuclear antigen (LANA) and its interacting proteins, such as CHD4. Neighboring terminal repeat (TR) fragments to lytic gene promoters drastically enhanced KSHV replication and transcription activator and LANA transcription regulatory functions. This study, thus, proposes a new latency-lytic switch model in which TR accessibility to the KSHV gene promoters regulates viral inducible gene expression.


Assuntos
Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Sarcoma de Kaposi , Humanos , Herpesvirus Humano 8/fisiologia , Histonas/genética , Histonas/metabolismo , Nucleossomos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Latência Viral/genética , Antígenos Virais/genética , Antígenos Virais/metabolismo , Sequências Repetidas Terminais/genética , Regulação Viral da Expressão Gênica
15.
EMBO Rep ; 25(2): 725-744, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177923

RESUMO

Viral infection often trigger an ATM serine/threonine kinase (ATM)-dependent DNA damage response in host cells that suppresses viral replication. Viruses evolved different strategies to counteract this antiviral surveillance system. Here, we report that human herpesvirus 6B (HHV-6B) infection causes genomic instability by suppressing ATM signaling in host cells. Expression of immediate-early protein 1 (IE1) phenocopies this phenotype and blocks homology-directed double-strand break repair. Mechanistically, IE1 interacts with NBS1, and inhibits ATM signaling through two distinct domains. HHV-6B seems to efficiently inhibit ATM signaling as further depletion of either NBS1 or ATM do not significantly boost viral replication in infected cells. Interestingly, viral integration of HHV-6B into the host's telomeres is not strictly dependent on NBS1, challenging current models where integration occurs through homology-directed repair. Given that spontaneous IE1 expression has been detected in cells of subjects with inherited chromosomally-integrated form of HHV-6B (iciHHV-6B), a condition associated with several health conditions, our results raise the possibility of a link between genomic instability and the development of iciHHV-6-associated diseases.


Assuntos
Herpesvirus Humano 6 , Proteínas Imediatamente Precoces , Infecções por Roseolovirus , Humanos , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/metabolismo , Infecções por Roseolovirus/genética , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Integração Viral , Instabilidade Genômica , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo
16.
Cancer Sci ; 115(2): 452-464, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38050664

RESUMO

B-cell receptor (BCR) signaling is critically activated and stable for mantle cell lymphoma (MCL), but the underlying mechanism of the activated BCR signaling pathway is not clear. The pathogenic basis of miR-17-92 cluster remains unclear although the oncogenic microRNA (miRNA) miR-17-92 cluster is highly expressed in patients with MCL. We revealed that miR-17-92 cluster overexpression is partly dependent on SOX11 expression and chromatin acetylation of MIR17HG enhancer regions. Moreover, miR-17-92 cluster regulates not only cell proliferation but BCR signaling activation in MCL cell lines. To comprehensively identify miR-17-92 cluster target genes, we performed pulldown-seq, where target RNA of miRNA was captured using the biotinylated miRNA mimics and magnetic bead-coated streptavidin, and quantified using next-generation sequencing. The pulldown-seq identified novel miRNA target genes, including tumor suppressors such as BTG2 (miR-19b), CDKN2A (miR-17), SYNE1 (miR-20a), TET2 (miR-18, miR-19b, and miR-92a), TNFRSF10A (miR-92a), and TRAF3 (miR-17). Notably, the gene expression profile data of patients with MCL revealed that BTG2 expression was negatively associated with that of BCR signature genes, and low BTG2 expression was associated with poor overall survival. Moreover, BTG2 silencing in MCL cell lines significantly induced BCR signaling overactivation and cell proliferation. Our results suggest an oncogenic role of miR-17-92 cluster-activating BCR signaling throughout BTG2 deregulation in MCL. Furthermore, this may contribute to the prediction of the therapeutic efficacy and improved outcomes of MCL.


Assuntos
Proteínas Imediatamente Precoces , Linfoma de Célula do Manto , MicroRNAs , Humanos , Adulto , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , MicroRNAs/metabolismo , Transdução de Sinais/genética , Linhagem Celular , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas Imediatamente Precoces/genética , Proteínas Supressoras de Tumor/metabolismo
17.
Int J Mol Sci ; 24(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38139431

RESUMO

The landscape of chromosomal aberrations in the tumor cells of the patients with B-ALL is diverse and can influence the outcome of the disease. Molecular karyotyping at the onset of the disease using chromosomal microarray (CMA) is advisable to identify additional molecular factors associated with the prognosis of the disease. Molecular karyotyping data for 36 patients with Ph-negative B-ALL who received therapy according to the ALL-2016 protocol are presented. We analyzed copy number alterations and their prognostic significance for CDKN2A/B, DMRTA, DOCK8, TP53, SMARCA2, PAX5, XPA, FOXE1, HEMGN, USP45, RUNX1, NF1, IGF2BP1, ERG, TMPRSS2, CRLF2, FGFR3, FLNB, IKZF1, RUNX2, ARID1B, CIP2A, PIK3CA, ATM, RB1, BIRC3, MYC, IKZF3, ETV6, ZNF384, PTPRJ, CCL20, PAX3, MTCH2, TCF3, IKZF2, BTG1, BTG2, RAG1, RAG2, ELK3, SH2B3, EP300, MAP2K2, EBI3, MEF2D, MEF2C, CEBPA, and TBLXR1 genes, choosing t(4;11) and t(7;14) as reference events. Of the 36 patients, only 5 (13.8%) had a normal molecular karyotype, and 31 (86.2%) were found to have various molecular karyotype abnormalities-104 deletions, 90 duplications or amplifications, 29 cases of cnLOH and 7 biallelic/homozygous deletions. We found that 11q22-23 duplication involving the BIRC3, ATM and MLL genes was the most adverse prognostic event in the study cohort.


Assuntos
Proteínas Imediatamente Precoces , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Humanos , Variações do Número de Cópias de DNA , Aberrações Cromossômicas , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , DNA , Perda de Heterozigosidade , Proteínas Nucleares/genética , Proteínas Imediatamente Precoces/genética , Proteínas Supressoras de Tumor/genética , Fatores de Troca do Nucleotídeo Guanina/genética
18.
Int J Mol Sci ; 24(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37834295

RESUMO

Prostate cancer (PCa) has a high prevalence and represents an important health problem, with an increased risk of metastasis. With the advance of CRISPR-Cas9 genome editing, new possibilities have been created for investigating PCa. The technique is effective in knockout oncogenes, reducing tumor resistance. MMP9 and miR-21 target genes are associated with PCa progression; therefore, we evaluated the MMP-9 and miR-21 targets in PCa using the CRISPR-Cas9 system. Single guide RNAs (sgRNAs) of MMP9 and miR-21 sequences were inserted into a PX-330 plasmid, and transfected in DU145 and PC-3 PCa cell lines. MMP9 and RECK expression was assessed by qPCR, WB, and IF. The miR-21 targets, integrins, BAX and mTOR, were evaluated by qPCR. Flow cytometry was performed with Annexin5, 7-AAD and Ki67 markers. Invasion assays were performed with Matrigel. The miR-21 CRISPR-Cas9-edited cells upregulated RECK, MARCKS, BTG2, and PDCD4. CDH1, ITGB3 and ITGB1 were increased in MMP9 and miR-21 CRISPR-Cas9-edited cells. Increased BAX and decreased mTOR were observed in MMP9 and miR-21 CRISPR-Cas9-edited cells. Reduced cell proliferation, increased apoptosis and low invasion in MMP9 and miR-21 edited cells was observed, compared to Scramble. CRISPR-Cas9-edited cells of miR-21 and MMP9 attenuate cell proliferation, invasion and stimulate apoptosis, impeding PCa evolution.


Assuntos
Proteínas Imediatamente Precoces , MicroRNAs , Neoplasias da Próstata , Masculino , Humanos , Edição de Genes , Sistemas CRISPR-Cas/genética , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , RNA Guia de Sistemas CRISPR-Cas , Proteína X Associada a bcl-2/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Supressoras de Tumor/genética , Proteínas de Ligação a RNA/metabolismo
19.
Curr Drug Targets ; 24(14): 1117-1126, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37904552

RESUMO

Serum and glucocorticoid-regulated kinases (SGK) are serine/threonine kinases that belong to AGC. The SGK-1, which responds to stress, controls a range of ion channels, cell growth, transcription factors, membrane transporters, cellular enzymes, cell survival, proliferation and death. Its expression is highly controlled by various factors such as hyperosmotic or isotonic oxidative stress, cell shrinkage, radiation, high blood sugar, neuronal injury, DNA damage, mechanical stress, thermal shock, excitement, dehydration and ischemia. The structural and functional deterioration that arises after a period of ischemia when blood flow is restored is referred to as ischemia/ reperfusion injury (I/R). The current review discusses the structure, expression, function and degradation of SGK-1 with special emphasis on the various ischemic injuries in different organs such as renal, myocardial, cerebral, intestinal and lungs. Furthermore, this review highlights the various therapeutic agents that activate the SGK-1 pathway and slow down the progression of I/R injuries.


Assuntos
Proteínas Imediatamente Precoces , Traumatismo por Reperfusão , Humanos , Sobrevivência Celular , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Isquemia
20.
Nat Commun ; 14(1): 4591, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524699

RESUMO

Herpes simplex virus 1 (HSV-1) infection and stress responses disrupt transcription termination by RNA Polymerase II (Pol II). In HSV-1 infection, but not upon salt or heat stress, this is accompanied by a dramatic increase in chromatin accessibility downstream of genes. Here, we show that the HSV-1 immediate-early protein ICP22 is both necessary and sufficient to induce downstream open chromatin regions (dOCRs) when transcription termination is disrupted by the viral ICP27 protein. This is accompanied by a marked ICP22-dependent loss of histones downstream of affected genes consistent with impaired histone repositioning in the wake of Pol II. Efficient knock-down of the ICP22-interacting histone chaperone FACT is not sufficient to induce dOCRs in ΔICP22 infection but increases dOCR induction in wild-type HSV-1 infection. Interestingly, this is accompanied by a marked increase in chromatin accessibility within gene bodies. We propose a model in which allosteric changes in Pol II composition downstream of genes and ICP22-mediated interference with FACT activity explain the differential impairment of histone repositioning downstream of genes in the wake of Pol II in HSV-1 infection.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Proteínas Imediatamente Precoces , Humanos , Histonas/metabolismo , Herpesvirus Humano 1/genética , Transcrição Gênica , Proteínas Virais/genética , Proteínas Virais/metabolismo , Herpes Simples/genética , Cromatina/genética , Cromatina/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo
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