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1.
Mol Cells ; 42(7): 530-545, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31362469

RESUMO

Tumor cells can vary epigenetically during ionizing irradiation (IR) treatment. These epigenetic variegations can influence IR response and shape tumor aggressiveness. However, epigenetic disturbance of histones after IR, implicating in IR responsiveness, has been elusive. Here, we investigate whether altered histone modification after IR can influence radiation responsiveness. The oncogenic CXCL12 mRNA and protein were more highly expressed in residual cancer cells from a hepatoma heterotopic murine tumor microenvironment and coculture of human hepatoma Huh7 and normal IMR90 cells after radiation. H3K4 methylation was also enriched and H3K9 methylation was decreased at its promoter region. Accordingly, invasiveness and the subpopulation of aggressive CD133+/CD24- cells increased after IR. Histone demethylase inhibitor IOX1 attenuated CXCL12 expression and the malignant subpopulation, suggesting that responses to IR can be partially mediated via histone modifications. Taken together, radiation-induced histone alterations at the CXCL12 promoter in hepatoma cells are linked to CXCL12 upregulation and increased aggressiveness in the tumor microenvironment.


Assuntos
Carcinoma Hepatocelular/genética , Quimiocina CXCL12/genética , Histonas/metabolismo , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Microambiente Tumoral/genética , Regulação para Cima/genética , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Quimiocina CXCL12/metabolismo , Epigênese Genética/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Compostos Heterocíclicos/farmacologia , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Processamento de Proteína Pós-Traducional/efeitos da radiação , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/metabolismo , Proteínas Recombinantes/farmacologia , Transcrição Genética/efeitos da radiação , Microambiente Tumoral/efeitos da radiação , Raios X
2.
Radiat Res ; 192(2): 121-134, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31161966

RESUMO

Radiation-induced fibrosis (RIF) is a common delayed effect of acute ionizing radiation exposure (DEARE) affecting diverse tissues including the heart, lungs, liver and skin, leading to reduced tissue function and increased morbidity. Monocytes, which may be classified into classical (CD14++, CD16-), intermediate (CD14++, CD16+) and non-classical (CD14+/low, CD16++) subtypes in humans and non-human primates (NHPs), and monocyte-derived macrophages may play an integral role in the pathogenesis of RIF. We tested the hypothesis that moderate to high levels of total-body exposure to radiation would alter monocyte polarization and produce phenotypes that could promote multi-organ fibrosis in a wellestablished NHP model of DEARE. Subjects were 16 young adult male rhesus macaques, ten of which were exposed to high-energy, 4 Gy X-ray total-body irradiation (TBI) and six that received sham irradiation (control). Total monocytes assessed by complete blood counts were 89% depleted in TBI animals by day 9 postirradiation (P < 0.05), but recovered by day 30 postirradiation and did not differ from control levels thereafter. Monocytes were isolated from peripheral blood mononuclear cells (PBMCs) and sorted into classical, intermediate and non-classical subsets using fluorescence-activated cell sorting (FACS) prior to and at 6 months post-TBI. At 6 months postirradiation, monocyte polarization shifted towards lower classical (92% → 86%) and higher intermediate (7% → 12%) and non-classical monocyte subsets (0.6% → 2%) (all P < 0.05) in TBI animals compared to baseline. No change in monocyte subsets was observed in control animals. Transcriptional profiles in classical and intermediate monocyte subsets were assessed using RNAseq. Classical monocyte gene expression did not change significantly over time or differ cross-sectionally between TBI and control groups. In contrast, significant numbers of differentially expressed genes (DEGs) were detected in intermediate monocyte comparisons between the TBI animals and all animals at baseline (304 DEGs), and in the TBI versus control animals at 6 months postirradiation (67 DEGs). Intermediate monocytes also differed between baseline and 6 months in control animals (147 DEGs). Pathway analysis was used to identify genes within significant canonical pathways, yielding 52 DEGs that were specific to irradiated intermediate monocytes. These DEGs and significant canonical pathways were associated with pro-fibrotic and anti-inflammatory signaling pathways that have been noted to induce M2 macrophage polarization. These findings support the hypothesis that TBI may alter monocyte programming and polarization towards a profibrotic phenotype, providing a novel target opportunity for therapies to inhibit or prevent RIF.


Assuntos
Monócitos/citologia , Monócitos/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Animais , Polaridade Celular/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Macaca mulatta , Masculino , Monócitos/metabolismo , Fatores de Tempo , Transcrição Genética/efeitos da radiação
3.
Nat Commun ; 10(1): 2630, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201314

RESUMO

Phytochromes initiate chloroplast biogenesis by activating genes encoding the photosynthetic apparatus, including photosynthesis-associated plastid-encoded genes (PhAPGs). PhAPGs are transcribed by a bacterial-type RNA polymerase (PEP), but how phytochromes in the nucleus activate chloroplast gene expression remains enigmatic. We report here a forward genetic screen in Arabidopsis that identified NUCLEAR CONTROL OF PEP ACTIVITY (NCP) as a necessary component of phytochrome signaling for PhAPG activation. NCP is dual-targeted to plastids and the nucleus. While nuclear NCP mediates the degradation of two repressors of chloroplast biogenesis, PIF1 and PIF3, NCP in plastids promotes the assembly of the PEP complex for PhAPG transcription. NCP and its paralog RCB are non-catalytic thioredoxin-like proteins that diverged in seed plants to adopt nonredundant functions in phytochrome signaling. These results support a model in which phytochromes control PhAPG expression through light-dependent double nuclear and plastidial switches that are linked by evolutionarily conserved and dual-localized regulatory proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Chaperonas Moleculares/metabolismo , Fitocromo/metabolismo , Transcrição Genética/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cloroplastos/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Plastídeos/genética , Plastídeos/metabolismo , Transdução de Sinais/fisiologia , Transcrição Genética/efeitos da radiação
4.
Nat Commun ; 10(1): 2629, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201355

RESUMO

Light initiates chloroplast biogenesis by activating photosynthesis-associated genes encoded by not only the nuclear but also the plastidial genome, but how photoreceptors control plastidial gene expression remains enigmatic. Here we show that the photoactivation of phytochromes triggers the expression of photosynthesis-associated plastid-encoded genes (PhAPGs) by stimulating the assembly of the bacterial-type plastidial RNA polymerase (PEP) into a 1000-kDa complex. Using forward genetic approaches, we identified REGULATOR OF CHLOROPLAST BIOGENESIS (RCB) as a dual-targeted nuclear/plastidial phytochrome signaling component required for PEP assembly. Surprisingly, RCB controls PhAPG expression primarily from the nucleus by interacting with phytochromes and promoting their localization to photobodies for the degradation of the transcriptional regulators PIF1 and PIF3. RCB-dependent PIF degradation in the nucleus signals the plastids for PEP assembly and PhAPG expression. Thus, our findings reveal the framework of a nucleus-to-plastid anterograde signaling pathway by which phytochrome signaling in the nucleus controls plastidial transcription.


Assuntos
Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Fitocromo/metabolismo , Tiorredoxinas/metabolismo , Transcrição Genética/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Plastídeos/genética , Plastídeos/metabolismo , Proteólise , Transdução de Sinais/fisiologia , Transcrição Genética/efeitos da radiação
5.
Radiat Res ; 192(1): 40-52, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31059377

RESUMO

The global threat of exposure to radiation and its subsequent outcomes require the development of effective strategies to mitigate immune cell injury. In this study we explored transcriptional and immunophenotypic characteristics of lymphoid organs of a non-human primate model after total-body irradiation (TBI). Fifteen middle-aged adult, ovariectomized, female cynomolgus macaques received a single dose of 0, 2 or 5 Gy gamma radiation. Thymus, spleen and lymph node from three controls and 2 Gy (n = 2) and 5 Gy (n = 2) exposed animals were assessed for molecular responses to TBI through microarray-based transcriptional profiling at day 5 postirradiation, and cellular changes through immunohistochemical (IHC) characterization of markers for B and T lymphocytes and macrophages across all 15 animals at time points up to 6 months postirradiation. Irradiated macaques developed acute hematopoietic syndrome. Analysis of array data at day 5 postirradiation identified transcripts with ≥2-fold difference from control and a false discovery rate (FDR) of Padj < 0.05 in lymph node (n = 666), spleen (n = 493) and thymus (n=3,014). Increasing stringency of the FDR to P < 0.001 reduced the number of genes to 71 for spleen and 379 for thymus. IHC and gene expression data demonstrated that irradiated animals had reduced numbers of T and B lymphocytes along with relative elevations of macrophages. Transcriptional analysis revealed unique patterns in primary and secondary lymphoid organs of cynomolgus macaques. Among the many differentially regulated transcripts, upregulation of noncoding RNAs [MIR34A for spleen and thymus and NEAT1 (NCRNA00084) for thymus] showed potential as biomarkers of radiation injury and targets for mitigating the effects of radiation-induced hematopoietic syndrome-impaired lymphoid reconstitution.


Assuntos
Linfócitos T/metabolismo , Linfócitos T/efeitos da radiação , Transcrição Genética/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Animais , Relação Dose-Resposta à Radiação , Feminino , Macaca fascicularis
6.
Exp Appl Acarol ; 77(4): 527-543, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31062204

RESUMO

Biological control of spider mites in hot and dry weather is a serious technical issue. A high-temperature adapted strain (HTAS) of the predatory mite Neoseiulus barkeri Hughes was selected from its conventional strain (CS), via long-term heat acclimation and frequent heat hardenings in our previous studies. However, the environment of high temperature is usually associated with enhanced ultraviolet (UV) radiation. In the present study, the physiological effects of UV-B radiation on survival rate and egg damage of N. barkeri were investigated, as well as the activities and expression profiles of antioxidant enzymes to UV-B radiation stress. UV-B radiation had deleterious effects on egg hatchability and survival of N. barkeri. Adults of the HTAS strain were less UV-B resistant than those of the CS strain; they also had lower levels of enzymatic activity of superoxide dismutase (SOD) and catalase against oxidative damage and weaker upregulation of SOD genes. The mRNA expression of three SOD genes of CS adult females immediately increased whereas that of HTAS showed almost no difference under UV-B stress for 1 h. The results showed the HTAS of N. barkeri had lower fitness under UV-B stress compared with the CS of N. barkeri. These results suggested that long-term heat acclimation may exert a profound impact on the developmental physiology of N. barkeri.


Assuntos
Proteínas de Artrópodes/genética , Aptidão Genética/efeitos da radiação , Ácaros/efeitos da radiação , Comportamento Predatório/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Adaptação Biológica , Animais , Antioxidantes/metabolismo , Proteínas de Artrópodes/metabolismo , Feminino , Temperatura Alta , Longevidade/efeitos da radiação , Ácaros/enzimologia , Ácaros/genética , Ácaros/fisiologia , Óvulo/fisiologia , Óvulo/efeitos da radiação , Controle Biológico de Vetores , Transcrição Genética/efeitos da radiação
7.
Retrovirology ; 16(1): 5, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30782173

RESUMO

BACKGROUND: Adult T-cell leukemia (ATL) is an aggressive neoplasm caused by human T-cell leukemia virus type 1 (HTLV-1). ATL carries a poor prognosis due to chemotherapy resistance. Thus, it is urgent to develop new treatment strategies. Hypericin (HY) is a new-type of photosensitizer in the context of photodynamic therapy (PDT) due to its excellent photosensitizing properties and anti-tumor activities. RESULTS: In the present study, we investigated the efficacy of hypericin in ATL cells. Clinically achievable concentrations of hypericin in association with PDT induced the inhibition of cell proliferation in ATL cell lines with minimal effect on peripheral blood CD4+ T lymphocytes. Moreover, hypericin-PDT treatment caused apoptosis and G2/M phase cell cycle arrest in leukemic cells. Western blot analyses revealed that hypericin-PDT treatment resulted in downregulation of Bcl-2 and enhanced the expression of Bad, cytochrome C, and AIF. Cleavage of caspases-3/-7/-9/-8, Bid, and PARP was increased in hypericin-PDT-treated ATL cells. In a luciferase assay, hypericin-PDT treatment was able to activate the promoter activity of Bax and p53, resulting in enhanced expression of Bax and p53 proteins. Finally, hypericin-PDT treatment suppressed the expression of viral protein HBZ and Tax by blocking the promoter activity via HTLV-1 5'LTR and 3'LTR. CONCLUSIONS: Our results revealed that hypericin-PDT is highly effective against ATL cells by induction of apoptosis and suppression of viral transcription. These studies highlight the promising use of hypericin-PDT as a targeted therapy for ATL.


Assuntos
Apoptose/efeitos dos fármacos , Vírus Linfotrópico T Tipo 1 Humano/efeitos dos fármacos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Luz , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Vírus Linfotrópico T Tipo 1 Humano/efeitos da radiação , Humanos , Modelos Biológicos , Perileno/farmacologia , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação , Ensaio Tumoral de Célula-Tronco
8.
Nat Commun ; 10(1): 542, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30710088

RESUMO

The suprachiasmatic nucleus (SCN) co-ordinates circadian behaviour and physiology in mammals. Its cell-autonomous circadian oscillations pivot around a well characterised transcriptional/translational feedback loop (TTFL), whilst the SCN circuit as a whole is synchronised to solar time by its retinorecipient cells that express and release vasoactive intestinal peptide (VIP). The cell-autonomous and circuit-level mechanisms whereby VIP synchronises the SCN are poorly understood. We show that SCN slices in organotypic culture demonstrate rapid and sustained circuit-level circadian responses to VIP that are mediated at a cell-autonomous level. This is accompanied by changes across a broad transcriptional network and by significant VIP-directed plasticity in the internal phasing of the cell-autonomous TTFL. Signalling via ERK1/2 and tuning by its negative regulator DUSP4 are critical elements of the VIP-directed circadian re-programming. In summary, we provide detailed mechanistic insight into VIP signal transduction in the SCN at the level of genes, cells and neural circuit.


Assuntos
Relógios Circadianos/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Tirosina Fosfatases/metabolismo , Núcleo Supraquiasmático/fisiologia , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Sistemas CRISPR-Cas , Relógios Circadianos/genética , Relógios Circadianos/efeitos da radiação , AMP Cíclico/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos da radiação , Redes Reguladoras de Genes/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos da radiação , Luz , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Camundongos Knockout , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/efeitos da radiação , Elementos de Resposta/genética , Núcleo Supraquiasmático/citologia , Núcleo Supraquiasmático/efeitos dos fármacos , Núcleo Supraquiasmático/efeitos da radiação , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação
9.
New Phytol ; 221(4): 1906-1918, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30252136

RESUMO

TGACG-BINDING FACTORs (TGAs) control the developmental or defense-related processes. In Arabidopsis thaliana, the functions of at least TGA2 and PERIANTHIA (PAN) can be repressed by interacting with CC-type glutaredoxins, which have the potential to control the redox state of target proteins. As TGA1 can be redox modulated in planta, we analyzed whether some of the 21 CC-type glutaredoxins (ROXYs) encoded in the Arabidopsis genome can influence TGA1 activity in planta and whether the redox active cysteines of TGA1 are functionally important. We show that the tga1 tga4 mutant and plants ectopically expressing ROXY8 or ROXY9 are impaired in hyponastic growth. As expression of ROXY8 and ROXY9 is activated upon transfer of plants from hyponasty-inducing low light to normal light, they might interfere with the growth-promoting function of TGA1/TGA4 to facilitate reversal of hyponastic growth. The redox-sensitive cysteines of TGA1 are not required for induction or reversal of hyponastic growth. TGA1 and TGA4 interact with ROXYs 8, 9, 18, and 19/GRX480, but ectopically expressed ROXY18 and ROXY19/GRX480 do not interfere with hyponastic growth. Our results therefore demonstrate functional specificities of individual ROXYs for distinct TGAs despite promiscuous protein-protein interactions and point to different repression mechanisms, depending on the TGA/ROXY combination.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Glutarredoxinas/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Domínio Catalítico , Cisteína/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Genes de Plantas , Glutarredoxinas/genética , Luz , Modelos Biológicos , Mutação/genética , Plantas Geneticamente Modificadas , Protoplastos/efeitos dos fármacos , Protoplastos/metabolismo , Protoplastos/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ácido Salicílico/farmacologia , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Transcriptoma/efeitos da radiação
10.
Int J Radiat Biol ; 95(5): 585-596, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30557071

RESUMO

BACKGROUND: The miR398 (microRNA398) posttranscriptionally regulates the superoxide dismutase (Cu/Zn-SOD). MATERIALS AND METHODS: The miR398 level was quantitated in gamma-irradiated (20Gy and 200Gy) and nitrogen-stressed seedlings by stem-loop RT-PCR (Real Time-Polymerase chain reaction). The positional preference of nucleotide (nt) for miR398 families and new targets was done. The SOD enzyme was assayed in native PAGE (Polyacrylamide gel electrophoresis). RESULTS: A relative increase in miR398-3p expression in the roots, and reduction in shoots for gamma-irradiated tissue and downregulation in miR398-5p in shoots is noted. The nitrogen stress shows upregulation of miR398-3p in roots and shoots, whereas the expression of miR398-5p is upregulated in roots and downregulated in shoots. Positional preference in miR398-3p for 1-14 nt is 90% conserved unlike miR398-5p where no nucleotide positional preference is seen. Targets obtained were functionally characterized. CONCLUSIONS: The mature miR398-5p and miR398-3p levels estimated in gamma-irradiated (20 and 200Gy) and nitrogen-stressed Medicago sativa seedlings show differential levels in roots and shoots. Native PAGE of Cu/Zn-SOD suggests its negative correlation with miR398 in shoots of irradiated and nitrogen-stressed samples. The nucleotide preferences for the nucleotide for a given position and functional characterization of targets are reported herein.


Assuntos
Raios gama/efeitos adversos , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Medicago sativa/genética , MicroRNAs/genética , Nitrogênio/fisiologia , Plântula/genética , Estresse Fisiológico/efeitos dos fármacos , Sequência de Bases , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Medicago sativa/fisiologia , Medicago sativa/efeitos da radiação , Plântula/fisiologia , Plântula/efeitos da radiação , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos da radiação , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação
11.
Development ; 145(23)2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30377170

RESUMO

The transition from skotomorphogenesis to photomorphogenesis is regulated in part by the COP1/SPA complex and phytochrome-interacting factors (PIFs) in Arabidopsis The constitutive photomorphogenic (cop) phenotypes of cop1 and spaQ mutants have been shown to result from a high abundance of positively acting transcription factors. Here, we show that the four major PIF proteins are unstable in cop1 mutants and that overexpression of PIF1, PIF3, PIF4 and PIF5 suppresses cop1 phenotypes in the dark. A comparison of the transcriptome data among cop1, spaQ and pifQ reveals remarkably overlapping gene expression profiles with preferential regulation of PIF direct target genes. Additionally, HFR1 strongly inhibits the in vivo binding and transcriptional activation activity of PIF1 in the dark. Taken together, these data suggest that the cop phenotypes of the cop1 and spaQ mutants are due to a combination of the reduced level of PIFs, increased levels of positively acting transcription factors (e.g. HY5/HFR1) and the HFR1-mediated inhibition of PIF-targeted gene expression in the dark. This article has an associated 'The people behind the papers' interview.


Assuntos
Arabidopsis/genética , Arabidopsis/efeitos da radiação , Luz , Morfogênese/genética , Morfogênese/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Modelos Biológicos , Mutação/genética , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica/efeitos da radiação , Proteólise/efeitos da radiação , Transcrição Genética/efeitos da radiação
12.
J Photochem Photobiol B ; 189: 193-200, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30391908

RESUMO

Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock, especially poultry and pigs. This study aimed to investigate how to inactivate IAVs by using different ultraviolet-light-emitting diodes (UV-LEDs). We developed sterilization equipment with light-emitting diodes (LEDs) those peak wavelengths were 365 nm (UVA-LED), 310 nm (UVB-LED), and 280 nm (UVC-LED). These UV-LED irradiations decreased dose fluence-dependent plaque-forming units of IAV H1N1 subtype (A/Puerto Rico/8/1934) infected Madin-Darby canine kidney (MDCK) cells, but the inactivation efficiency of UVA-LED was significantly lower than UVB- and UVC-LED. UV-LED irradiations did not alter hemagglutination titer, but decreased accumulation of intracellular total viral RNA in infected MDCK cells was observed. Additionally, UV-LED irradiations suppressed the accumulation of intracellular mRNA (messenger RNA), vRNA (viral RNA), and cRNA (complementary RNA), as measured by strand-specific RT-PCR. These results suggest that UV-LEDs inhibit host cell replication and transcription of viral RNA. Both UVB- and UVC-LED irradiation decreased focus-forming unit (FFU) of H5N1 subtype (A/Crow/Kyoto/53/2004), a highly pathogenic avian IAV (HPAI), in infected MDCK cells, and the amount of FFU were lower than the H1N1 subtype. From these results, it appears that IAVs may have different sensitivity among the subtypes, and UVB- and UVC-LED may be suitable for HPAI virus inactivation.


Assuntos
Vírus da Influenza A/efeitos da radiação , Raios Ultravioleta , Inativação de Vírus/efeitos da radiação , Animais , Cães , Humanos , Vírus da Influenza A Subtipo H1N1 , Células Madin Darby de Rim Canino/virologia , Infecções por Orthomyxoviridae , RNA Viral/biossíntese , RNA Viral/genética , Transcrição Genética/efeitos da radiação , Replicação Viral/efeitos da radiação
13.
Med Phys ; 45(11): e1111-e1122, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30421807

RESUMO

PURPOSE: Radiogenomics is the study of genomic changes that underlie the radioresponse of normal and tumor tissues. And while this is generally regarded as a whole genome approach, one must keep in mind the impact of single gene biology on radioresponse, (ataxia telangiectasia, Nijmegen breakage syndrome). METHODS: This review begins with the association of single nucleotide polymorphisms in the DNA with adverse normal tissue events to the prediction of therapeutic outcome after radiotherapy. From there it covers transcriptome (protein coding RNA transcripts) analysis, which is where the greatest understanding of the molecular signaling responsible for the radioresponse of tumors and normal tissues is known. Non-protein coding RNA transcripts (miRNA, lncRNA), transcribed from what was once thought of as junk DNA, are now known to be negative regulators of the transcription of mRNA by multiple mechanisms. miRNA can act as tumor suppressors or oncogenes regulating a diverse range of cellular processes that drive radioresponse and biosignatures that predict outcome after radiotherapy are described. RESULTS: Biological signatures that explain differences in radioresponse based upon cell type, biological signatures that predict surviving fraction at 2 Gy and signatures that identify hypoxia have been described. The omics analysis of the response of mammalian cells to charged particle, predominantly proton and carbon ions, is less mature than that seen with low LET radiation exposures. However, there appear to be responses after charged particle exposure that parallel the responses seem with low LET exposures. This commonality of response is centered around the downstream signaling of p53. There are also novel omics responses to charged particles that help explain the response of tumors to charged particle exposures. For instance, signaling pathways associated with angiogenesis, vasculogenesis, migration and invasion appear to be downregulated in a number of cell types when exposed to charged particles. This response supports both in vitro and in vivo data suggesting that tumors exposed to charged particles are less invasive, unlike the response of tumors to low LET exposures. Profoundly lacking for low LET and charged particle exposures are predictive or prognostic signatures of radioresponse or tumor physiology affecting radioresponse that have been validated in prospective clinical trials. For example, the identification of low LET tumor radioresistance could be used as a marker of patient eligibility for carbon therapy. Tissue specific signatures, or accurate imaging of hypoxic regions, could be used for charged particle selection to overcome hypoxia per se, or could be used to prescribe a high LET therapeutic boost to a hypoxic region of a tumor. CONCLUSIONS: Integrating radiogenomics into radiation oncology has the potential to personalize an already precise form of cancer therapy.


Assuntos
Genômica , Radiobiologia , Humanos , Neoplasias/genética , Neoplasias/radioterapia , Transcrição Genética/efeitos da radiação
14.
J Transl Med ; 16(1): 221, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-30097062

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection is strongly associated with hepatocellular carcinoma due to the main pathogenic X protein of HBV (HBx). Whether HBV infection and the HBx protein could result in macular degeneration (MD) is not known. The aim of this study is to assess the association and underlying mechanisms between HBV infection and MD. METHODS: The National Health Research Institutes in Taiwan built a large database, the National Health Insurance Research Database (NHIRD), which includes the claims data from the Taiwan National Health Insurance (NHI) program. The Taiwan NHI is a single-payer, compulsory health insurance program for Taiwan citizens. The data for the present study were derived from the Longitudinal Health Insurance Database, which contains the claims data of 1 million insured people within the NHIRD, including beneficiary registration, inpatient and outpatient files, drug use, and other medical services. In this study, we first investigated the association of HBV infection and the risk of MD by a population-based cohorts study enrolling 39,796 HBV-infected patients and 159,184 non-HBV-infected patients. RESULTS: After adjustment of age, sex, and comorbidities, the risk of MD was significantly higher in the HBV-infected cohort than in the non-HBV-infected cohort (adjusted HR = 1.31; 95% CI = 1.17-1.46). In vitro, we provided evidence to demonstrate that overexpression of HBx in the human retinal pigment epithelial (RPE) cell line, ARPE19, significantly reduced cell viability and clonogenic survival upon UV and blue light irradiation. By gene microarray analysis, we further showed that almost all genes in DNA repair pathways including base excision repair, nucleotide excision repair, mismatch repair, and homologous recombination were significantly down-regulated in the UV-induced cell death of HBx-transfected ARPE19 cells. CONCLUSIONS: The HBx protein may sensitize RPE cells to UV and blue light irradiation and increase the risk of HBV-infection-associated MD through down-regulation of multiple DNA repair pathways.


Assuntos
Células Epiteliais/efeitos da radiação , Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Degeneração Macular/patologia , Degeneração Macular/virologia , Epitélio Pigmentado da Retina/patologia , Transativadores/metabolismo , Raios Ultravioleta , Adulto , Morte Celular/efeitos da radiação , Linhagem Celular , Proliferação de Células/efeitos da radiação , Forma Celular/efeitos da radiação , Estudos de Coortes , Células Epiteliais/patologia , Feminino , Ontologia Genética , Redes Reguladoras de Genes , Hepatite B/genética , Humanos , Degeneração Macular/genética , Masculino , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Modelos de Riscos Proporcionais , Fatores de Risco , Transcrição Genética/efeitos da radiação
15.
In Vitro Cell Dev Biol Anim ; 54(8): 589-599, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30083841

RESUMO

Application of high-dosage UVB irradiation in phototherapeutic dermatological treatments present health concerns attributed to UV-exposure. In assessing UV-induced photobiological damage, we investigated dose-dependent effects of UVB irradiation on human keratinocyte cells (HaCaT). Our study implemented survival and apoptosis assays and revealed an unexpected dose response wherein higher UVB-dosage induced higher viability. Established inhibitors, such as AKT- (LY294002), PKC- (Gö6976, and Rottlerin), ERK- (PD98059), P38 MAPK- (SB203580), and JNK- (SP600125), were assessed to investigate UV-induced apoptotic pathways. Despite unobvious contributions of known signaling pathways in dose-response mediation, microarray analysis identified transcriptional expression of UVB-response genes related to the respiratory-chain. Observed correlation of ROS-production with UVB irradiation potentiated ROS as the underlying mechanism for observed dose responses. Inability of established pathways to explain such responses suggests the complex nature underlying UVB-phototherapy response.


Assuntos
Queratinócitos/efeitos da radiação , Raios Ultravioleta , Acetofenonas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Benzopiranos/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Transporte de Elétrons/efeitos da radiação , Flavonoides/farmacologia , Perfilação da Expressão Gênica , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Óxido Nítrico/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação
16.
Bioorg Chem ; 80: 492-497, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29990897

RESUMO

miRNAs are key cellular regulators and their dysregulation is associated with many human diseases. They are usually produced locally in a spatiotemporally controlled manner to target mRNAs and regulate gene expression. Thus, developing chemical tools for manipulating miRNA with spatiotemporal precise is critical for studying miRNA. Herein, we designed a strategy to control miRNA biogenesis with light controllable inhibitor targeting the pre-miRNA processing by Dicer. By conjugating two non-inhibiting units, a low affinity Dicer inhibitor and a pre-miRNA binder, through a photocleavable linker, the bifunctional molecule obtained could inhibit miRNA production. Taking advantage of the photocleavable property of the linker, the bifunctional inhibitor can be fragmented into separate non-inhibiting units and therefore be deactivated by light. We expect that this strategy could be applied to generate chemical biological tools that allow light-mediated spatiotemporal control of miRNA maturation and contribute to the study of miRNA function.


Assuntos
RNA Helicases DEAD-box/metabolismo , MicroRNAs/metabolismo , Ribonuclease III/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Desenho de Drogas , Humanos , Luz , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , Processamento Pós-Transcricional do RNA/efeitos da radiação , Proteínas Recombinantes/metabolismo , Transcrição Genética/efeitos dos fármacos , Transcrição Genética/efeitos da radiação
17.
Cell Rep ; 24(3): 585-593.e4, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30021157

RESUMO

In response to blue light, cryptochromes photoexcite and interact with signal partners to transduce signal almost synchronously in plants. The detailed mechanism of CRY-mediated light signaling remains unclear: the photobiochemical reactions of cryptochrome are transient and synchronous, thus making the monitoring and analysis of each step difficult in plant cells. In this study, we reconstituted the Arabidopsis CRY2 signaling pathway in mammalian cells and investigated the biological role of Arabidopsis CRY2 in this heterologous system, eliminating the interferences of other plant proteins. Our results demonstrated that, besides being the light receptor, Arabidopsis CRY2 binds to DNA directly and acts as a transcriptional activator in a blue-light-enhanced manner. Similar to classic transcription factors, we found that the transcriptional activity of CRY2 is regulated by its dimerization and phosphorylation. In addition, CRY2 cooperates with CIB1 to regulate transcription by enhancing the DNA affinity and transcriptional activity of CIB1 under blue light.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Criptocromos/metabolismo , DNA/metabolismo , Transdução de Sinais , Transcrição Genética , Arabidopsis/efeitos da radiação , Células HEK293 , Humanos , Luz , Transdução de Sinal Luminoso/efeitos da radiação , Fosforilação/efeitos da radiação , Ligação Proteica/efeitos da radiação , Multimerização Proteica/efeitos da radiação , Transcrição Genética/efeitos da radiação , Ativação Transcricional/genética
18.
Crit Rev Biochem Mol Biol ; 53(5): 453-474, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30040498

RESUMO

On-cue regulation of gene transcription is an invaluable tool for the study of biological processes and the development and integration of next-generation therapeutics. Ideal reagents for the precise regulation of gene transcription should be nontoxic to the host system, highly tunable, and provide a high level of spatial and temporal control. Light, when coupled with protein or small molecule-linked photoresponsive elements, presents an attractive means of meeting the demands of an ideal system for regulating gene transcription. In this review, we cover recent developments in the burgeoning field of light-regulated gene transcription, covering both genetically encoded and small-molecule based strategies for optical regulation of transcription during the period 2012 till present.


Assuntos
Optogenética/métodos , Transcrição Genética/efeitos da radiação , Animais , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Luz , Engenharia de Proteínas/métodos , Proteínas/genética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Ativação Transcricional/efeitos da radiação
19.
Radiat Environ Biophys ; 57(3): 241-249, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29850926

RESUMO

Transcriptional dosimetry is an emergent field of radiobiology aimed at developing robust methods for detecting and quantifying absorbed doses using radiation-induced fluctuations in gene expression. A combination of RNA sequencing, array-based and quantitative PCR transcriptomics in cellular, murine and various ex vivo human models has led to a comprehensive description of a fundamental set of genes with demonstrable dosimetric qualities. However, these are yet to be validated in human tissue due to the scarcity of in situ-irradiated source material. This represents a major hurdle to the continued development of transcriptional dosimetry. In this study, we present a novel evaluation of a previously reported set of dosimetric genes in human tissue exposed to a large therapeutic dose of radiation. To do this, we evaluated the quantitative changes of a set of dosimetric transcripts consisting of FDXR, BAX, BCL2, CDKN1A, DDB2, BBC3, GADD45A, GDF15, MDM2, SERPINE1, TNFRSF10B, PLK3, SESN2 and VWCE in guided pre- and post-radiation (2 weeks) prostate cancer biopsies from seven patients. We confirmed the prolonged dose-responsivity of most of these transcripts in in situ-irradiated tissue. BCL2, GDF15, and to some extent TNFRSF10B, were markedly unreliable single markers of radiation exposure. Nevertheless, as a full set, these genes reliably segregated non-irradiated and irradiated tissues and predicted radiation absorption on a patient-specific basis. We also confirmed changes in the translated protein product for a small subset of these dosimeters. This study provides the first confirmatory evidence of an existing dosimetric gene set in less-accessible tissues-ensuring peripheral responses reflect tissue-specific effects. Further work will be required to determine if these changes are conserved in different tissue types, post-radiation times and doses.


Assuntos
Proteômica , Transcrição Genética/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Radioisótopos de Irídio/uso terapêutico , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Radiometria
20.
J Exp Bot ; 69(16): 3933-3947, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29897568

RESUMO

The phytohormones brassinosteroid (BR), auxin, and gibberellin (GA) regulate photomorphogenesis-related hypocotyl elongation in Arabidopsis via the co-operative interaction of BZR-ARF-PIF/DELLA (BAP/D) transcription factors/regulators. In addition, ethylene activates the PIF3 or ERF1 pathway through EIN3/EIL1 to balance hypocotyl elongation in Arabidopsis seedlings. However, the mechanism by which ethylene is co-ordinated with other phytohormones to produce light-regulated hypocotyl growth remains elusive. In this study, we found that hypocotyl cell elongation is regulated by a network involving ethylene, auxin, and BR signalling, which is mediated by interactions among ERF72, ARF6, and BZR1. ERF72 interacted directly with ARF6 and BZR1 in vitro and in vivo, and it antagonised regulation by ARF6 and BZR1 of the transcription of BEE3 and XTH7. In addition, light modulated the subcellular localisation of ERF72 and transcription of ERF72 through the EIN2-EIN3/EIL1 pathway, facilitating the function of ERF72 in photomorphogenesis. The expression of BEE3 and XTH7 was also regulated by the EIN2-EIN3/EIL1 pathway. Our findings indicate that a revised BZR-ARF-PIF/DELLA-ERF (BAP/DE) module integrates light and hormone signals to regulate hypocotyl elongation in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Hipocótilo/crescimento & desenvolvimento , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Escuridão , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Proteínas Nucleares/genética , Reguladores de Crescimento de Planta/metabolismo , Plantas Geneticamente Modificadas , Ligação Proteica , RNA de Plantas/genética , Análise de Sequência de RNA , Transdução de Sinais , Frações Subcelulares/metabolismo , Fatores de Transcrição/genética , Transcrição Genética/efeitos da radiação
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