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1.
PLoS One ; 15(8): e0236781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776961

RESUMO

It has been reported that Bach1-deficient mice show reduced tissue injuries in diverse disease models due to increased expression of heme oxygenase-1 (HO-1)that possesses an antioxidant function. In contrast, we found that Bach1 deficiency in mice exacerbated skeletal muscle injury induced by cardiotoxin. Inhibition of Bach1 expression in C2C12 myoblast cells using RNA interference resulted in reduced proliferation, myotube formation, and myogenin expression compared with control cells. While the expression of HO-1 was increased by Bach1 silencing in C2C12 cells, the reduced myotube formation was not rescued by HO-1 inhibition. Up-regulations of Smad2, Smad3 and FoxO1, known inhibitors of muscle cell differentiation, were observed in Bach1-deficient mice and Bach1-silenced C2C12 cells. Therefore, Bach1 may promote regeneration of muscle by increasing proliferation and differentiation of myoblasts.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diferenciação Celular , Músculo Esquelético/fisiologia , Mioblastos/citologia , Regeneração , Proteínas Smad/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Fatores de Transcrição de Zíper de Leucina Básica/genética , Linhagem Celular , Técnicas de Silenciamento de Genes , Inativação Gênica , Camundongos , Músculo Esquelético/citologia , Transcriptoma/genética
2.
Proc Natl Acad Sci U S A ; 117(31): 18840-18848, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690706

RESUMO

Light and gravity are two key environmental factors that control plant growth and architecture. However, the molecular basis of the coordination of light and gravity signaling in plants remains obscure. Here, we report that two classes of transcription factors, PHYTOCHROME INTERACTING FACTORS (PIFs) and ELONGATED HYPOCOTYL5 (HY5), can directly bind and activate the expression of LAZY4, a positive regulator of gravitropism in both shoots and roots in Arabidopsis In hypocotyls, light promotes degradation of PIFs to reduce LAZY4 expression, which inhibits the negative gravitropism of hypocotyls. LAZY4 overexpression can partially rescue the negative gravitropic phenotype of pifq in the dark without affecting amyloplast development. Our identification of the PIFs-LAZY4 regulatory module suggests the presence of another role for PIF proteins in gravitropism, in addition to a previous report demonstrating that PIFs positively regulate amyloplast development to promote negative gravitropism in hypocotyls. In roots, light promotes accumulation of HY5 proteins to activate expression of LAZY4, which promotes positive gravitropism in roots. Together, our data indicate that light exerts opposite regulation of LAZY4 expression in shoots and roots by mediating the protein levels of PIFs and HY5, respectively, to inhibit the negative gravitropism of shoots and promote positive gravitropism of roots in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Fatores de Transcrição de Zíper de Leucina Básica , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Gravitropismo/efeitos da radiação , Proteínas Nucleares , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Luz , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
3.
Gene ; 761: 144971, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32707301

RESUMO

Diabetic nephropathy (DN) is a serious microvascular complication of diabetes across the world. Recently, many circular RNAs (circRNAs) can exert a crucial role in DN progression. Our investigation was designed to study whether circ_0123996 was associated with DN and aimed to find out the underlying mechanisms. We observed that circ_0123996 expression was significantly increased in Type 2 diabetes (T2D) with DN in comparison to those patients without DN. Consistently, circ_0123996 was also obviously elevated in DN mice models and high glucose (HG)-incubated MMCs. Then, it was proved transfection of circ_0123996 siRNA in mice mesangial cells (MMCs) restrained MMCs proliferation greatly. In addition, it was demonstrated that decrease of circ_0123996 alleviated fibrosis-related protein expression including FN and Col-4 in MMCs. Next, it was confirmed by our study that circ_0123996 can serve as a sponge for miR-149-5p. miR-149-5p has been identified in several diseases including diabetes. At present, we observed that miR-149-5p was decreased in DN. Overexpression of miR-149-5p greatly repressed the effect of circ_0123996 on MMCs. BTB and CNC homology 1 (Bach1) is reported in various disease including some vascular diseases.Here, Bach1 was confirmed as a target of miR-149-5p. Circ_0123996 upregulated Bach1 expression and restrained MMCs proliferation and fibrosis through sponging miR-149-5p. Thus, it was revealed that circ_0123996 was involved in DN via sponging miR-149-5p and modulating Bach1 expression.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/biossíntese , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Nefropatias Diabéticas/metabolismo , MicroRNAs/metabolismo , RNA Circular/metabolismo , Adulto , Animais , Apoptose/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/genética , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrose/genética , Fibrose/metabolismo , Humanos , Masculino , Células Mesangiais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Circular/genética
4.
Mol Cell ; 79(4): 546-560.e7, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32589964

RESUMO

Translational control targeting the initiation phase is central to the regulation of gene expression. Understanding all of its aspects requires substantial technological advancements. Here we modified yeast translation complex profile sequencing (TCP-seq), related to ribosome profiling, and adapted it for mammalian cells. Human TCP-seq, capable of capturing footprints of 40S subunits (40Ss) in addition to 80S ribosomes (80Ss), revealed that mammalian and yeast 40Ss distribute similarly across 5'TRs, indicating considerable evolutionary conservation. We further developed yeast and human selective TCP-seq (Sel-TCP-seq), enabling selection of 40Ss and 80Ss associated with immuno-targeted factors. Sel-TCP-seq demonstrated that eIF2 and eIF3 travel along 5' UTRs with scanning 40Ss to successively dissociate upon AUG recognition; notably, a proportion of eIF3 lingers on during the initial elongation cycles. Highlighting Sel-TCP-seq versatility, we also identified four initiating 48S conformational intermediates, provided novel insights into ATF4 and GCN4 mRNA translational control, and demonstrated co-translational assembly of initiation factor complexes.


Assuntos
Complexos Multiproteicos/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Biossíntese de Proteínas , Ribossomos/metabolismo , Regiões 5' não Traduzidas , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Códon de Iniciação , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 3 em Eucariotos/genética , Fator de Iniciação 3 em Eucariotos/metabolismo , Células HEK293 , Humanos , Complexos Multiproteicos/genética , Fatores de Iniciação de Peptídeos/genética , Subunidades Ribossômicas Menores de Eucariotos/genética , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Ribossomos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
5.
Mol Cell Biol ; 40(14)2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32366381

RESUMO

Proteasomes are protease complexes essential for cellular homeostasis, and their activity is crucial for cancer cell growth. However, the mechanism of how proteasome activity is maintained in cancer cells has remained unclear. The CNC family transcription factor NFE2L1 induces the expression of almost all proteasome-related genes under proteasome inhibition. Both NFE2L1 and its phylogenetically closest homolog, NFE2L3, are highly expressed in several types of cancer, such as colorectal cancer. Here, we demonstrate that NFE2L1 and NFE2L3 complementarily maintain basal proteasome activity in cancer cells. Double knockdown of NFE2L1 and NFE2L3 impaired basal proteasome activity in cancer cells and cancer cell resistance to a proteasome inhibitor anticancer drug, bortezomib, by significantly reducing the basal expression of seven proteasome-related genes: PSMB3, PSMB7, PSMC2, PSMD3, PSMG2, PSMG3, and POMP Interestingly, the molecular basis behind these cellular consequences was that NFE2L3 repressed NFE2L1 translation by the induction of the gene encoding the translational regulator CPEB3, which binds to the NFE2L1 3' untranslated region and decreases polysome formation on NFE2L1 mRNA. Consistent results were obtained from clinical analysis, wherein patients with cancer having tumors expressing higher levels of CPEB3/NFE2L3 exhibit poor prognosis. These results provide the novel regulatory mechanism of basal proteasome activity in cancer cells through an NFE2L3-CPEB3-NFE2L1 translational repression axis.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fator 1 Relacionado a NF-E2/metabolismo , Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Linhagem Celular Tumoral , Humanos , Biossíntese de Proteínas
6.
Nucleic Acids Res ; 48(10): 5426-5441, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32356892

RESUMO

Activator protein 1 (AP-1) is one of the largest families of basic leucine zipper (bZIP) transcription factors in eukaryotic cells. How AP-1 proteins achieve target DNA binding specificity remains elusive. In Saccharomyces cerevisiae, the AP-1-like protein (Yap) family comprises eight members (Yap1 to Yap8) that display distinct genomic target sites despite high sequence homology of their DNA binding bZIP domains. In contrast to the other members of the Yap family, which preferentially bind to short (7-8 bp) DNA motifs, Yap8 binds to an unusually long DNA motif (13 bp). It has been unclear what determines this unique specificity of Yap8. In this work, we use molecular and biochemical analyses combined with computer-based structural design and molecular dynamics simulations of Yap8-DNA interactions to better understand the structural basis of DNA binding specificity determinants. We identify specific residues in the N-terminal tail preceding the basic region, which define stable association of Yap8 with its target promoter. We propose that the N-terminal tail directly interacts with DNA and stabilizes Yap8 binding to the 13 bp motif. Thus, beside the core basic region, the adjacent N-terminal region contributes to alternative DNA binding selectivity within the AP-1 family.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/química , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , DNA Fúngico/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , DNA Fúngico/química , Proteínas de Membrana Transportadoras/genética , Simulação de Dinâmica Molecular , Mutação , Regiões Promotoras Genéticas , Ligação Proteica , Elementos de Resposta , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
7.
Proc Natl Acad Sci U S A ; 117(23): 12531-12540, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32414922

RESUMO

An increase in nutrient dose leads to proportional increases in crop biomass and agricultural yield. However, the molecular underpinnings of this nutrient dose-response are largely unknown. To investigate, we assayed changes in the Arabidopsis root transcriptome to different doses of nitrogen (N)-a key plant nutrient-as a function of time. By these means, we found that rate changes of genome-wide transcript levels in response to N-dose could be explained by a simple kinetic principle: the Michaelis-Menten (MM) model. Fitting the MM model allowed us to estimate the maximum rate of transcript change (V max), as well as the N-dose at which one-half of V max was achieved (K m) for 1,153 N-dose-responsive genes. Since transcription factors (TFs) can act in part as the catalytic agents that determine the rates of transcript change, we investigated their role in regulating N-dose-responsive MM-modeled genes. We found that altering the abundance of TGA1, an early N-responsive TF, perturbed the maximum rates of N-dose transcriptomic responses (V max), K m, as well as the rate of N-dose-responsive plant growth. We experimentally validated that MM-modeled N-dose-responsive genes included both direct and indirect TGA1 targets, using a root cell TF assay to detect TF binding and/or TF regulation genome-wide. Taken together, our results support a molecular mechanism of transcriptional control that allows an increase in N-dose to lead to a proportional change in the rate of genome-wide expression and plant growth.


Assuntos
Regulação da Expressão Gênica de Plantas , Nitrogênio/metabolismo , Desenvolvimento Vegetal , Transcriptoma , Arabidopsis , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Cinética
8.
Artigo em Inglês | MEDLINE | ID: mdl-32339912

RESUMO

In plants, basic leucine zipper (bZIP) transcription factors (TFs) participate in various biological processes such as development and stress responses. But the molecular mechanism of wheat bZIP TFs modulating abscisic acid (ABA) biosynthesis is unknown. In this study, we demonstrated the expressions of three bZIP TF genes TabZIP8, 9, 13, were regulated by Triticum aestivum calcium (Ca2+)-dependent protein kinase 9-1 (TaCDPK9-1) and they took part in ABA biosynthesis in wheat roots under salt stress. We first isolated TabZIP8, 9, 13 and TaCDPK9-1 from wheat. TabZIP8, 9, 13 genes transcripts were strongly induced by salt stress, but salt-induced TabZIP8, 9, 13 transcriptions were drastically impaired by Ca2+ channel blocker LaCl3. TaCDPK9-1 kinase could interact with TabZIP8, 9, 13 TFs through yeast two-hybrid assay. Next, the expression levels of salt-induced wheat 9-cis-epoxycarotenoid dioxygenase1, 2 (TaNCED1,2) encoding a key enzyme controlling ABA production and salt-induced ABA content were found to be decreased under LaCl3 treatment, and yeast one-hybrid experiment revealed TabZIP8, 9, 13 could bind to the ABA-responsive elements (ABREs) and the promoter sequence of TaNCED2 gene. Together, our results suggest that salt stress-induced ABA accumulation is mediated by TabZIP8, 9, 13, which are adjusted by TaCDPK9-1 in wheat roots.


Assuntos
Ácido Abscísico , Proteínas de Plantas , Proteínas Quinases , Estresse Fisiológico , Triticum , Ácido Abscísico/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Proteínas Quinases/metabolismo , Cloreto de Sódio/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Triticum/genética , Triticum/metabolismo
9.
Arch Biochem Biophys ; 687: 108387, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32348741

RESUMO

Although acetaminophen (APAP) is a commonly used analgesic antipyretic drug, hepatotoxicity and nephrotoxicity are common after the overdose. The main mechanism of APAP toxicity is oxidative stress based. Stress may induce the production of heme oxygenase 1 (HO)-1 which is regulated by interleukin (IL)-10 and inhibit the production of tumor necrosis factor-alpha (TNF-α). HO-1 expression is further regulated by nuclear factor erythroid 2-related factor 2 (Nrf2) and the transcription factor BTB and CNC homology 1 (BACH1). Drug-induced toxicity can be relieved by several natural products, which are preferred due to their dietary nature and less adverse reactions. Of these natural products, omega-3 (ω-3) fatty acids are known for anti-inflammatory and antioxidant actions. However, effects of ω-3fatty acids on APAP-induced hepatic and renal toxicity are not well addressed. We designed this study to test the potential protecting actions of ω-3 fatty acids (270 mg/kg Eicosapentaenoic acid and 180 mg/kg docosahexaenoic acid, orally, for 7 days) in hepatotoxicity and nephrotoxicity induced by APAP (2 g/kg, once orally on day 7) in rats. Moreover, we focused on the molecular mechanism underlying APAP hepatotoxicity and nephrotoxicity. Pre-treatment with ω-3 fatty acids enhanced liver and kidney functions indicated by decreased serum aminotransferases activities and serum creatinine and urea concentrations. These results were further confirmed by histopathological examination. Moreover, ω-3 fatty acids showed antioxidant properties confirmed by decreased malondialdehyde level and increased total antioxidant capacity. Antioxidant Nrf2, its regulators (HO-1 and BACH1) and the anti-inflammatory cytokine (IL-10) were up-regulated by APAP administration as a compensatory mechanism and they were normalized by ω-3 fatty acids. ω-3 fatty acids showed anti-inflammatory actions through down-regulating nuclear factor kappa B (NF-ĸB) and its downstream TNF-α. Moreover, Western blot analysis showed that ω-3 fatty acids promoted Nrf2 translocation to the nucleus; BACH1 exit from the nucleus and inhibited NF-ĸB nuclear translocation. These findings suggested the protecting actions of ω-3 fatty acids against APAP-induced hepatic and renal toxicity through regulation of antioxidant Nrf2 and inflammatory NF-ĸB pathways.


Assuntos
Anti-Inflamatórios/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Ácidos Graxos Ômega-3/farmacologia , Nefropatias/prevenção & controle , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Acetaminofen , Animais , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Núcleo Celular/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação para Baixo , Heme Oxigenase (Desciclizante)/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Fígado/patologia , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Ratos Sprague-Dawley , Proteínas Repressoras/metabolismo , Fator de Crescimento Transformador alfa/metabolismo
10.
Nat Commun ; 11(1): 1592, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221308

RESUMO

ELONGATED HYPOCOTYL 5 (HY5), a basic domain/leucine zipper (bZIP) transcription factor, acts as a master regulator of transcription to promote photomorphogenesis. At present, it's unclear whether HY5 uses additional mechanisms to inhibit hypocotyl elongation. Here, we demonstrate that HY5 enhances the activity of GSK3-like kinase BRASSINOSTEROID-INSENSITIVE 2 (BIN2), a key repressor of brassinosteroid signaling, to repress hypocotyl elongation. We show that HY5 physically interacts with and genetically acts through BIN2 to inhibit hypocotyl elongation. The interaction of HY5 with BIN2 enhances its kinase activity possibly by the promotion of BIN2 Tyr200 autophosphorylation, and subsequently represses the accumulation of the transcription factor BRASSINAZOLE-RESISTANT 1 (BZR1). Leu137 of HY5 is found to be important for the HY5-BIN2 interaction and HY5-mediated regulation of BIN2 activity, without affecting the transcriptional activity of HY5. HY5 levels increase with light intensity, which gradually enhances BIN2 activity. Thus, our work reveals an additional way in which HY5 promotes photomorphogenesis, and provides an insight into the regulation of GSK3 activity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Hipocótilo/metabolismo , Luz , Proteínas Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Brassinosteroides/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Quinase 3 da Glicogênio Sintase , Fosforilação , Proteínas Quinases/genética , Fatores de Transcrição/metabolismo
11.
Mol Cell Biol ; 40(10)2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32123008

RESUMO

Proteasomes are essential protease complexes that maintain cellular homeostasis, and aberrant proteasomal activity supports cancer development. The regulatory mechanisms and biological function of the ubiquitin-26S proteasome have been studied extensively, while those of the ubiquitin-independent 20S proteasome system remain obscure. Here, we show that the cap 'n' collar (CNC) family transcription factor NRF3 specifically enhances 20S proteasome assembly in cancer cells and that 20S proteasomes contribute to colorectal cancer development through ubiquitin-independent proteolysis of the tumor suppressor p53 and retinoblastoma (Rb) proteins. The NRF3 gene is highly expressed in many cancer tissues and cell lines and is important for cancer cell growth. In cancer cells, NRF3 upregulates the assembly of the 20S proteasome by directly inducing the gene expression of the 20S proteasome maturation protein POMP. Interestingly, NRF3 knockdown not only increases p53 and Rb protein levels but also increases p53 activities for tumor suppression, including cell cycle arrest and induction of apoptosis. Furthermore, protein stability and cell viability assays using two distinct proteasome inhibitor anticancer drugs, the 20S proteasome inhibitor bortezomib and the ubiquitin-activating enzyme E1 inhibitor TAK-243, show that the upregulation of the NRF3-POMP axis leads to ubiquitin-independent proteolysis of p53 and Rb and to impaired sensitivity to bortezomib but not TAK-243. More importantly, the NRF3-POMP axis supports tumorigenesis and metastasis, with higher NRF3/POMP expression levels correlating with poor prognoses in patients with colorectal or rectal adenocarcinoma. These results suggest that the NRF3-POMP-20S proteasome assembly axis is significant for cancer development via ubiquitin-independent proteolysis of tumor suppressor proteins.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Chaperonas Moleculares/metabolismo , Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína do Retinoblastoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Células HCT116 , Células HeLa , Humanos , Proteólise , Ubiquitina/metabolismo
12.
Nucleic Acids Res ; 48(7): 3567-3590, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32086516

RESUMO

To sustain iron homeostasis, microorganisms have evolved fine-tuned mechanisms for uptake, storage and detoxification of the essential metal iron. In the human pathogen Aspergillus fumigatus, the fungal-specific bZIP-type transcription factor HapX coordinates adaption to both iron starvation and iron excess and is thereby crucial for virulence. Previous studies indicated that a HapX homodimer interacts with the CCAAT-binding complex (CBC) to cooperatively bind bipartite DNA motifs; however, the mode of HapX-DNA recognition had not been resolved. Here, combination of in vivo (genetics and ChIP-seq), in vitro (surface plasmon resonance) and phylogenetic analyses identified an astonishing plasticity of CBC:HapX:DNA interaction. DNA motifs recognized by the CBC:HapX protein complex comprise a bipartite DNA binding site 5'-CSAATN12RWT-3' and an additional 5'-TKAN-3' motif positioned 11-23 bp downstream of the CCAAT motif, i.e. occasionally overlapping the 3'-end of the bipartite binding site. Phylogenetic comparison taking advantage of 20 resolved Aspergillus species genomes revealed that DNA recognition by the CBC:HapX complex shows promoter-specific cross-species conservation rather than regulon-specific conservation. Moreover, we show that CBC:HapX interaction is absolutely required for all known functions of HapX. The plasticity of the CBC:HapX:DNA interaction permits fine tuning of CBC:HapX binding specificities that could support adaptation of pathogens to their host niches.


Assuntos
Aspergillus fumigatus/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fator de Ligação a CCAAT/metabolismo , Proteínas Fúngicas/metabolismo , Ferro/metabolismo , Regiões Promotoras Genéticas , Sequência Rica em At , Aspergillus fumigatus/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/química , Sítios de Ligação , DNA Fúngico/química , DNA Fúngico/metabolismo , Evolução Molecular , Proteínas Fúngicas/química , Mutação , Motivos de Nucleotídeos , Ligação Proteica , Domínios Proteicos , Regulon , Sideróforos/metabolismo , Ressonância de Plasmônio de Superfície , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
13.
Plant Cell Rep ; 39(4): 553-565, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060604

RESUMO

KEY MESSAGE: Overexpression of the tea plant gene CsbZIP18 in Arabidopsis impaired freezing tolerance, and CsbZIP18 is a negative regulator of ABA signaling and cold stress. Basic region/leucine zipper (bZIP) transcription factors play important roles in the abscisic acid (ABA) signaling pathway and abiotic stress response in plants. However, few bZIP transcription factors have been functionally characterized in tea plants (Camellia sinensis). In this study, a bZIP transcription factor, CsbZIP18, was found to be strongly induced by natural cold acclimation, and the expression level of CsbZIP18 was lower in cold-resistant cultivars than in cold-susceptible cultivars. Compared with wild-type (WT) plants, Arabidopsis plants constitutively overexpressing CsbZIP18 exhibited decreased sensitivity to ABA, increased levels of relative electrolyte leakage (REL) and reduced values of maximal quantum efficiency of photosystem II (Fv/Fm) under freezing conditions. The expression of ABA homeostasis- and signal transduction-related genes and abiotic stress-inducible genes, such as RD22, RD26 and RAB18, was suppressed in overexpression lines under freezing conditions. However, there was no significant change in the expression of genes involved in the C-repeat binding factor (CBF)-mediated ABA-independent pathway between WT and CsbZIP18 overexpression plants. These results indicate that CsbZIP18 is a negative regulator of freezing tolerance via an ABA-dependent pathway.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Camellia sinensis/genética , Resposta ao Choque Frio , Congelamento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Aclimatação/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Camellia sinensis/metabolismo , Resposta ao Choque Frio/genética , Regulação da Expressão Gênica de Plantas/genética , Complexo de Proteína do Fotossistema II/metabolismo , Filogenia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteostase/efeitos dos fármacos , Proteostase/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
14.
Plant Cell Rep ; 39(4): 473-487, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32016506

RESUMO

KEY MESSAGE: The non-intrinsic ABC proteins ABCI20 and ABCI21 are induced by light under HY5 regulation, localize to the ER, and ameliorate cytokinin-driven growth inhibition in young Arabidopsis thaliana seedlings. The plant ATP-binding cassette (ABC) I subfamily (ABCIs) comprises heterogeneous proteins containing any of the domains found in other ABC proteins. Some ABCIs are known to function in basic metabolism and stress responses, but many remain functionally uncharacterized. ABCI19, ABCI20, and ABCI21 of Arabidopsis thaliana cluster together in a phylogenetic tree, and are suggested to be targets of the transcription factor ELONGATED HYPOCOTYL 5 (HY5). Here, we reveal that these three ABCIs are involved in modulating cytokinin responses during early seedling development. The ABCI19, ABCI20 and ABCI21 promoters harbor HY5-binding motifs, and ABCI20 and ABCI21 expression was induced by light in a HY5-dependent manner. abci19 abci20 abci21 triple and abci20 abci21 double knockout mutants were hypersensitive to cytokinin in seedling growth retardation assays, but did not show phenotypic differences from the wild type in either control medium or auxin-, ABA-, GA-, ACC- or BR-containing media. ABCI19, ABCI20, and ABCI21 were expressed in young seedlings and the three proteins interacted with each other, forming a large protein complex at the endoplasmic reticulum (ER) membrane. These results suggest that ABCI19, ABCI20, and ABCI21 fine-tune the cytokinin response at the ER under the control of HY5 at the young seedling stage.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Citocininas/metabolismo , Retículo Endoplasmático/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Motivos de Aminoácidos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Citocininas/genética , Retículo Endoplasmático/efeitos da radiação , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Técnicas de Inativação de Genes , Luz , Filogenia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Ligação Proteica , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Plântula/efeitos da radiação
15.
Proc Natl Acad Sci U S A ; 117(4): 2084-2091, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932421

RESUMO

BRCA1 promotes error-free, homologous recombination-mediated repair (HRR) of DNA double-stranded breaks (DSBs). When excessive and uncontrolled, BRCA1 HRR activity promotes illegitimate recombination and genome disorder. We and others have observed that the BRCA1-associated protein RAP80 recruits BRCA1 to postdamage nuclear foci, and these chromatin structures then restrict the amplitude of BRCA1-driven HRR. What remains unclear is how this process is regulated. Here we report that both BRCA1 poly-ADP ribosylation (PARsylation) and the presence of BRCA1-bound RAP80 are critical for the normal interaction of BRCA1 with some of its partners (e.g., CtIP and BACH1) that are also known components of the aforementioned focal structures. Surprisingly, the simultaneous loss of RAP80 and failure therein of BRCA1 PARsylation results in the dysregulated accumulation in these foci of BRCA1 complexes. This in turn is associated with the intracellular development of a state of hyper-recombination and gross chromosomal disorder. Thus, physiological RAP80-BRCA1 complex formation and BRCA1 PARsylation contribute to the kinetics by which BRCA1 HRR-sustaining complexes normally concentrate in nuclear foci. These events likely contribute to aneuploidy suppression.


Assuntos
Proteína BRCA1/metabolismo , Proteínas de Ligação a DNA/metabolismo , Chaperonas de Histonas/metabolismo , Reparo de DNA por Recombinação , Proteína BRCA1/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Cromossomos/genética , Cromossomos/metabolismo , Dano ao DNA , Proteínas de Ligação a DNA/genética , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Chaperonas de Histonas/genética , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Poli ADP Ribosilação , Ligação Proteica
16.
Nat Commun ; 11(1): 252, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937752

RESUMO

Differentiation and homeostasis of Foxp3+ regulatory T (Treg) cells are strictly controlled by T-cell receptor (TCR) signals; however, molecular mechanisms that govern these processes are incompletely understood. Here we show that Bach2 is an important regulator of Treg cell differentiation and homeostasis downstream of TCR signaling. Bach2 prevents premature differentiation of fully suppressive effector Treg (eTreg) cells, limits IL-10 production and is required for the development of peripherally induced Treg (pTreg) cells in the gastrointestinal tract. Bach2 attenuates TCR signaling-induced IRF4-dependent Treg cell differentiation. Deletion of IRF4 promotes inducible Treg cell differentiation and rescues pTreg cell differentiation in the absence of Bach2. In turn, loss of Bach2 normalizes eTreg cell differentiation of IRF4-deficient Treg cells. Mechanistically, Bach2 counteracts the DNA-binding activity of IRF4 and limits chromatin accessibility, thereby attenuating IRF4-dependent transcription. Thus, Bach2 balances TCR signaling induced transcriptional activity of IRF4 to maintain homeostasis of thymically-derived and peripherally-derived Treg cells.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Diferenciação Celular/imunologia , Cromatina/metabolismo , Colite/imunologia , Modelos Animais de Doenças , Epigênese Genética/imunologia , Fatores de Transcrição Forkhead/metabolismo , Trato Gastrointestinal/imunologia , Regulação da Expressão Gênica/imunologia , Homeostase/imunologia , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/metabolismo , Interleucina-10/biossíntese , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo
17.
Immunity ; 52(2): 295-312.e11, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31924477

RESUMO

Specialized regulatory T (Treg) cells accumulate and perform homeostatic and regenerative functions in nonlymphoid tissues. Whether common precursors for nonlymphoid-tissue Treg cells exist and how they differentiate remain elusive. Using transcription factor nuclear factor, interleukin 3 regulated (Nfil3) reporter mice and single-cell RNA-sequencing (scRNA-seq), we identified two precursor stages of interleukin 33 (IL-33) receptor ST2-expressing nonlymphoid tissue Treg cells, which resided in the spleen and lymph nodes. Global chromatin profiling of nonlymphoid tissue Treg cells and the two precursor stages revealed a stepwise acquisition of chromatin accessibility and reprogramming toward the nonlymphoid-tissue Treg cell phenotype. Mechanistically, we identified and validated the transcription factor Batf as the driver of the molecular tissue program in the precursors. Understanding this tissue development program will help to harness regenerative properties of tissue Treg cells for therapy.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfonodos/imunologia , Baço/imunologia , Linfócitos T Reguladores/citologia , Transferência Adotiva , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Fatores de Transcrição de Zíper de Leucina Básica/genética , Diferenciação Celular/genética , Cromatina/metabolismo , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Camundongos , Especificidade de Órgãos/imunologia , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Linfócitos T Reguladores/metabolismo
18.
Life Sci ; 244: 117331, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31972209

RESUMO

AIM: Drug-induced liver and kidney injuries are worldwide problems that cause restrictions in the use of drugs. The injury is highly mediated by oxidative stress and inflammation pathways. So, demonstrating the role of the natural compound (Vit.D) on the prevention of acetaminophen (APAP) overdose toxicity and the molecular mechanism through NrF2/BACH1/HO-1 pathway is promising. EXPERIMENTAL: Male Sprague Dawley rats (40 rats) were divided randomly into 4 groups: Normal, APAP, APAP+Vit.D (500 IU/kg) and APAP+Vit.D (1000 IU/kg). The APAP toxicity caused by 2 g/kg (orally) on day 7. KEY FINDINGS: Vit D decreased significantly liver and kidney functions: serum ALT and AST activities (P < 0.0005); creatinine and urea (P < 0.0005) concentrations; liver and kidney histopathological scores. Furthermore, Vit.D ameliorated APAP-caused oxidative stress through the liver malondialdehyde concentration's decrease and the total antioxidant capacity's increase (P < 0.0005). The molecular mechanism of Vit.D may include the prevention of high deteriorating increase of oxidative stress mediators: hepatic and renal NrF2 and BACH1 tissue expression in addition to serum HO-1 (P < 0.0005); the increase of inflammatory mediators; hepatic and renal NF-κB tissue expression, serum interleukin-10 (P < 0.0005) and TNF-α (P < 0.05). The 500 IU/kg Vit.D administration caused better protection results especially on the histopathological and immunohistochemical results than the 1000 IU/kg Vit.D administration. SIGNIFICANCE: Vit.D ameliorates APAP-induced liver and kidney injury that may be attributed to its ability to moderately increase antioxidant status to counteract the toxicity without the massive destructive increase in the anti-oxidant pathway (NrF2/HO-1/BACH1). So, this work represents a great prophylactic role of Vit.D against drug-induced liver and kidney injury.


Assuntos
Acetaminofen/toxicidade , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Heme Oxigenase (Desciclizante)/metabolismo , Rim/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Repressoras/metabolismo , Vitamina D/administração & dosagem , Doença Aguda , Analgésicos não Entorpecentes/toxicidade , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/genética , Rim/metabolismo , Rim/patologia , Masculino , Fator 2 Relacionado a NF-E2/genética , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/genética , Vitaminas/administração & dosagem
19.
FASEB J ; 34(1): 865-880, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914686

RESUMO

Intramembrane cleavage of transmembrane proteins is a fundamental cellular process to produce important signals that elicit biological responses. These proteolytic events are known as regulated intramembrane proteolysis (RIP). ATF6 and BBF2H7 are transmembrane basic leucine zipper transcription factors and are subjected to RIP by site-1 protease (S1P) and site-2 protease (S2P) sequentially in response to endoplasmic reticulum (ER) stress. However, the detailed mechanisms responsible for RIP of the transcription factors, including the precise cutting sites, are still unknown. In this study, we demonstrated that S1P cleaves BBF2H7 just before the RXXL S1P recognition motif. Conversely, S2P cut at least three different sites in the membrane (next to Leu380, Met381, and Leu385), indicating that S2P cleaves the substrates at variable sites or via a multistep process. Interestingly, we found BBF2H7-derived small peptide (BSP) fragments located between the S1P and S2P cleavage sites in cells exposed to ER stress. Major type of BSP fragments was composed of 45 amino acid including partial transmembrane and luminal regions and easily aggregates like amyloid ß (Aß) protein. These results advance the understanding of poorly characterized ER stress-dependent RIP. Furthermore, the aggregable peptides produced by ER stress could link to the pathophysiology of neurodegenerative disorders.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/metabolismo , Proteólise , Fator 6 Ativador da Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Humanos , Fragmentos de Peptídeos/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Transcrição Genética/fisiologia
20.
Development ; 147(3)2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31915147

RESUMO

Identification of cell type-specific cis-regulatory elements (CREs) is crucial for understanding development and disease, although identification of functional regulatory elements remains challenging. We hypothesized that context-specific CREs could be identified by context-specific non-coding RNA (ncRNA) profiling, based on the observation that active CREs produce ncRNAs. We applied ncRNA profiling to identify rod and cone photoreceptor CREs from wild-type and mutant mouse retinas, defined by presence or absence, respectively, of the rod-specific transcription factor (TF) Nrl Nrl-dependent ncRNA expression strongly correlated with epigenetic profiles of rod and cone photoreceptors, identified thousands of candidate rod- and cone-specific CREs, and identified motifs for rod- and cone-specific TFs. Colocalization of NRL and the retinal TF CRX correlated with rod-specific ncRNA expression, whereas CRX alone favored cone-specific ncRNA expression, providing quantitative evidence that heterotypic TF interactions distinguish cell type-specific CRE activity. We validated the activity of novel Nrl-dependent ncRNA-defined CREs in developing cones. This work supports differential ncRNA profiling as a platform for the identification of cell type-specific CREs and the discovery of molecular mechanisms underlying TF-dependent CRE activity.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas do Olho/metabolismo , Sequências Reguladoras de Ácido Nucleico/genética , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Transcrição Genética/genética , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas do Olho/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Masculino , Camundongos , Camundongos Knockout , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Transativadores/genética , Transativadores/metabolismo , Transcriptoma
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