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1.
Nat Commun ; 11(1): 4882, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32985505

RESUMO

T helper cell differentiation requires lineage-defining transcription factors and factors that have shared expression among multiple subsets. BATF is required for development of multiple Th subsets but functions in a lineage-specific manner. BATF is required for IL-9 production in Th9 cells but in contrast to its function as a pioneer factor in Th17 cells, BATF is neither sufficient nor required for accessibility at the Il9 locus. Here we show that STAT5 is the earliest factor binding and remodeling the Il9 locus to allow BATF binding in both mouse and human Th9 cultures. The ability of STAT5 to mediate accessibility for BATF is observed in other Th lineages and allows acquisition of the IL-9-secreting phenotype. STAT5 and BATF convert Th17 cells into cells that mediate IL-9-dependent effects in allergic airway inflammation and anti-tumor immunity. Thus, BATF requires the STAT5 signal to mediate plasticity at the Il9 locus.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Interleucina-9/imunologia , Fator de Transcrição STAT5/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Diferenciação Celular , Feminino , Humanos , Interleucina-9/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT5/genética , Linfócitos T Auxiliares-Indutores/citologia , Células Th17/imunologia
2.
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
4.
PLoS One ; 15(8): e0237540, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804965

RESUMO

The yeast MAP kinase Hog1 pathway activates transcription of several hundreds genes. Large-scale gene expression and DNA binding assays suggest that most Hog1-induced genes are regulated by the transcriptional activators Msn2/4, Hot1 and Sko1. These studies also revealed the target genes of each activator and the putative binding sites on their promoters. In a previous study we identified a group of genes, which we considered the bona fide targets of Hog1, because they were induced in response to expression of intrinsically active mutant of Hog1, in the absence of any stress. We previously analyzed the promoter of the most highly induced gene, STL1, and noticed that some promoter properties were different from those proposed by large-scale data. We therefore continue to study promoters individually and present here analyses of promoters of more Hog1's targets, RTC3, HSP12, DAK1 and ALD3. We report that RTC3 and HSP12 promoters are robust and are induced, to different degrees, even in cells lacking all four activators. DAK1 and ALD3 promoters are not robust and fully depend on a single activator, DAK1 on Sko1 and ALD3 on Msn2/4. Most of these observations could not be inferred from the large-scale data. Msn2/4 are involved in regulating all four promoters. It was assumed, therefore, that the promoters are spontaneously active in ras2Δ cells, in which Msn2/4 are known to be de-repressed. Intriguingly, the promoters were not active in BY4741ras2Δ cells, but were de-repressed, as expected, in ras2Δ cells of other genetic backgrounds. This study describes two phenomena. One, some Hog1's target promoters are most robust, backupped by many activators. Second, in contrast to most laboratory strains, the widely used BY4741 strain does not induce Msn2/4 activity when the Ras/cAMP cascade is downregulated.


Assuntos
Proteínas de Choque Térmico/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Fatores de Transcrição de Zíper de Leucina Básica/genética , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Choque Térmico/química , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética
5.
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
6.
PLoS Genet ; 16(7): e1008908, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32639995

RESUMO

The human fungal pathogen Candida albicans is constantly exposed to environmental challenges impacting the cell wall. Signaling pathways coordinate stress adaptation and are essential for commensalism and virulence. The transcription factors Sko1, Cas5, and Rlm1 control the response to cell wall stress caused by the antifungal drug caspofungin. Here, we expand the Sko1 and Rlm1 transcriptional circuit and demonstrate that Rlm1 activates Sko1 cell wall stress signaling. Caspofungin-induced transcription of SKO1 and several Sko1-dependent cell wall integrity genes are attenuated in an rlm1Δ/Δ mutant strain when compared to the treated wild-type strain but not in a cas5Δ/Δ mutant strain. Genome-wide chromatin immunoprecipitation (ChIP-seq) results revealed numerous Sko1 and Rlm1 directly bound target genes in the presence of caspofungin that were undetected in previous gene expression studies. Notable targets include genes involved in cell wall integrity, osmolarity, and cellular aggregation, as well as several uncharacterized genes. Interestingly, we found that Rlm1 does not bind to the upstream intergenic region of SKO1 in the presence of caspofungin, indicating that Rlm1 indirectly controls caspofungin-induced SKO1 transcription. In addition, we discovered that caspofungin-induced SKO1 transcription occurs through self-activation. Based on our ChIP-seq data, we also discovered an Rlm1 consensus motif unique to C. albicans. For Sko1, we found a consensus motif similar to the known Sko1 motif for Saccharomyces cerevisiae. Growth assays showed that SKO1 overexpression suppressed caspofungin hypersensitivity in an rlm1Δ/Δ mutant strain. In addition, overexpression of the glycerol phosphatase, RHR2, suppressed caspofungin hypersensitivity specifically in a sko1Δ/Δ mutant strain. Our findings link the Sko1 and Rlm1 signaling pathways, identify new biological roles for Sko1 and Rlm1, and highlight the complex dynamics underlying cell wall signaling.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Candida albicans/efeitos dos fármacos , Caspofungina/farmacologia , Proteínas de Domínio MADS/genética , Proteínas Repressoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Antifúngicos/farmacologia , Candida albicans/genética , Candida albicans/patogenicidade , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Humanos , Fosforilação/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética
7.
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
8.
BMC Infect Dis ; 20(1): 403, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517725

RESUMO

BACKGROUND: Current tools for diagnosing latent TB infection (LTBI) detect immunological memory of past exposure but are unable to determine whether exposure is recent. We sought to identify a whole-blood transcriptome signature of recent TB exposure. METHODS: We studied household contacts of TB patients; healthy volunteers without recent history of TB exposure; and patients with active TB. We performed whole-blood RNA sequencing (in all), an interferon gamma release assay (IGRA; in contacts and healthy controls) and PET/MRI lung scans (in contacts only). We evaluated differentially-expressed genes in household contacts (log2 fold change ≥1 versus healthy controls; false-discovery rate < 0.05); compared these to differentially-expressed genes seen in the active TB group; and assessed the association of a composite gene expression score to independent exposure/treatment/immunological variables. RESULTS: There were 186 differentially-expressed genes in household contacts (n = 26, age 22-66, 46% male) compared with healthy controls (n = 5, age 29-38, 100% male). Of these genes, 141 (76%) were also differentially expressed in active TB (n = 14, age 27-69, 71% male). The exposure signature included genes from inflammatory response, type I interferon signalling and neutrophil-mediated immunity pathways; and genes such as BATF2 and SCARF1 known to be associated with incipient TB. The composite gene-expression score was higher in IGRA-positive contacts (P = 0.04) but not related to time from exposure, isoniazid prophylaxis, or abnormalities on PET/MRI (all P > 0.19). CONCLUSIONS: Transcriptomics can detect TB exposure and, with further development, may be an approach of value for epidemiological research and targeting public health interventions.


Assuntos
Tuberculose Latente/diagnóstico , RNA/sangue , Adulto , Idoso , Fatores de Transcrição de Zíper de Leucina Básica/genética , Estudos de Casos e Controles , Busca de Comunicante , Feminino , Humanos , Interferon Tipo I/metabolismo , Tuberculose Latente/microbiologia , Tuberculose Latente/transmissão , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/metabolismo , Mapas de Interação de Proteínas/genética , RNA/química , RNA/metabolismo , Receptores Depuradores Classe F/genética , Proteínas Supressoras de Tumor/genética , Adulto Jovem
9.
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
10.
Gene ; 756: 144912, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32574760

RESUMO

Assessment of existing diversity is the key for germplasm conservation and crop improvement. Wheat (Triticum aestivum L.) is among the most important cereal crop and consumed by two billion world's populations. DNA-based markers are predominantly used for diversity characterization because they are easy to develop and not influenced by environment. Among them microsatellites (simple sequence repeats, SSRs) are most suitable due to their genome-wide distribution, hypervariability and reproducibility for their applications in diversity, genetic improvement, and molecular breeding. bZIP transcription factors play major roles in plants in light and stress signalling, seed development, and defence. A total of 846 SSRs were identified from 370 wheat cDNA sequences and a sub-set of 35 polymorphic TabZIPMS (TriticumaestivumbZIP MicroSatellites) was used for diversity and genetic structure analysis of 92 Indian wheat varieties and related species. 114 SSR variants ranging from 2 to 5 per SSR locus were detected for 35 SSRs in the varieties. Average polymorphic information content (PIC) and observed heterozygosity was found to be 0.135 and 0.838, respectively. Thirty-four SSRs showed cross-transferability into different related species. Combined Bayesian model and Jaccard's similarity based genetic clustering analysis revealed two clusters of 80 bread wheat varieties and one separate cluster of related species. In this study, a total 35 novel bZIP-derived SSRs were identified in a set 370 bZIP genes and shown high polymorphism and cross-species transferability in wheat. The findings provide resources for future utilization in genetic resource conservation, trait introgression, breeding and varietal development.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Repetições de Microssatélites , Proteínas de Plantas/genética , Triticum/genética , Marcadores Genéticos , Filogenia , Triticum/classificação
11.
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
12.
Mol Cell ; 78(5): 890-902.e6, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32416068

RESUMO

Acidic transcription activation domains (ADs) are encoded by a wide range of seemingly unrelated amino acid sequences, making it difficult to recognize features that promote their dynamic behavior, "fuzzy" interactions, and target specificity. We screened a large set of random 30-mer peptides for AD function in yeast and trained a deep neural network (ADpred) on the AD-positive and -negative sequences. ADpred identifies known acidic ADs within transcription factors and accurately predicts the consequences of mutations. Our work reveals that strong acidic ADs contain multiple clusters of hydrophobic residues near acidic side chains, explaining why ADs often have a biased amino acid composition. ADs likely use a binding mechanism similar to avidity where a minimum number of weak dynamic interactions are required between activator and target to generate biologically relevant affinity and in vivo function. This mechanism explains the basis for fuzzy binding observed between acidic ADs and targets.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Fatores de Transcrição/genética , Ativação Transcricional/genética , Sequência de Aminoácidos/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas de Ligação a DNA/metabolismo , Aprendizado Profundo , Ligação Proteica , Domínios Proteicos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional/fisiologia
13.
Proc Natl Acad Sci U S A ; 117(24): 13740-13749, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32471947

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) is the etiologic agent of a T cell neoplasm and several inflammatory diseases. A viral gene, HTLV-1 bZIP factor (HBZ), induces pathogenic Foxp3-expressing T cells and triggers systemic inflammation and T cell lymphoma in transgenic mice, indicating its significance in HTLV-1-associated diseases. Here we show that, unexpectedly, a proinflammatory cytokine, IL-6, counteracts HBZ-mediated pathogenesis. Loss of IL-6 accelerates inflammation and lymphomagenesis in HBZ transgenic mice. IL-6 innately inhibits regulatory T cell differentiation, suggesting that IL-6 functions as a suppressor against HBZ-associated complications. HBZ up-regulates expression of the immunosuppressive cytokine IL-10. IL-10 promotes T cell proliferation only in the presence of HBZ. As a mechanism of growth promotion by IL-10, HBZ interacts with STAT1 and STAT3 and modulates the IL-10/JAK/STAT signaling pathway. These findings suggest that HTLV-1 promotes the proliferation of infected T cells by hijacking the machinery of regulatory T cell differentiation. IL-10 induced by HBZ likely suppresses the host immune response and concurrently promotes the proliferation of HTLV-1 infected T cells.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Interleucina-6/imunologia , Linfoma/virologia , Proteínas dos Retroviridae/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Diferenciação Celular , Proliferação de Células , Infecções por HTLV-I/genética , Infecções por HTLV-I/patologia , Infecções por HTLV-I/virologia , Interações Hospedeiro-Patógeno , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Linfoma/genética , Linfoma/imunologia , Linfoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Retroviridae/genética , Linfócitos T Reguladores/imunologia
14.
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
15.
Arch Endocrinol Metab ; 64(2): 138-143, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32236312

RESUMO

Objective Type 1 diabetes mellitus (T1DM) is an autoimmune disorder caused by a complex interaction between environmental and genetic risk factors. BTB domain and CNC homolog 2 (BACH2) gene encodes a transcription factor that acts on the differentiation and formation of B and T lymphocytes. BACH2 is also involved in the suppression of apoptosis and inflammation in pancreatic beta-cells, indicating a role for it in the development of T1DM. Therefore, the aim of this study was to evaluate the association of the BACH2 rs11755527 single nucleotide polymorphism (SNP) with T1DM. Subjects and methods This case-control study comprised 475 patients with T1DM and 598 nondiabetic individuals. The BACH2 rs11755527 (C/G) SNP was genotyped using real-time PCR with TaqMan MGB probes. Results Genotype distributions of rs11755527 SNP were in accordance with frequencies predicted by the Hardy-Weinberg equilibrium in case and control groups and were similar between groups (P = 0.729). The minor allele frequency was 43.6% in cases and 42.5% in controls (P = 0.604). Moreover, the G allele frequency did not differ between groups when considering different inheritance models and adjusting for age, gender, body mass index, and HLA DR/DQ genotypes of high-risk for T1DM. Although, well-known high-risk T1DM HLA DR/DQ genotypes were associated with T1DM in our population [OR= 7.42 (95% CI 3.34 - 17.0)], this association was not influenced by the rs11755527 SNP. Conclusion The BACH2 rs11755527 SNP seems not to be associated with T1DM in a Brazilian population.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Adulto , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco
16.
Physiol Plant ; 169(3): 369-379, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32208521

RESUMO

Plants have evolved light signaling mechanisms to optimally adapt developmental patterns to the ambient light environments. CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) and LONG HYPOCOTYL5 (HY5) are two critical components in the light signaling pathway in Arabidopsis thaliana. COP1 acts as an E3 ubiquitin ligase that targets positive regulators, such as HY5, leading to their degradation in darkness. However, functional analysis of the COP1-HY5 module in maize (Zea mays) has not been reported. Here, we investigated the expression patterns and roles of the COP1 and HY5 orthologs, ZmCOP1 and ZmHY5, in regulating photomorphogenesis. These two genes have high amino acid identities with their Arabidopsis homolog and were both regulated by light. Subcellular localization assay showed that ZmCOP1 was distributed in the cytosol and ZmHY5 localized in the nucleus. Exogenous expression of ZmCOP1 rescued the physiological defects of the cop1-4 mutant, and expression of ZmHY5 complemented the long hypocotyl phenotype of the hy5-215 mutant in Arabidopsis. Yeast two-hybrid and fluorescence resonance energy transfer assays showed that ZmCOP1 interacted with ZmHY5. Our study gains insight into the conserved function and regulatory mechanism of the COP1-HY5 signaling pathway in maize and Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Regulação da Expressão Gênica de Plantas , Luz , Proteínas Nucleares/genética , Ligação Proteica , Ubiquitina-Proteína Ligases , Zea mays
17.
BMC Cancer ; 20(1): 184, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131762

RESUMO

BACKGROUND: Casein kinase II (CK2) is involved in multiple tumor-relevant signaling pathways affecting proliferation and apoptosis. CK2 is frequently upregulated in acute B-lymphoblastic leukemia (B-ALL) and can be targeted by the ATP-competitive CK2 inhibitor CX-4945. While reduced proliferation of tumor entities including B-ALL after CX-4945 incubation has been shown in vitro and in vivo, the detailed way of action is unknown. Here, we investigated the influence on the PI3K/AKT and apoptosis cascades in vivo and in vitro for further clarification. METHODS: A B-ALL xenograft model in NSG mice was used to perform in vivo longitudinal bioluminescence imaging during six day CX-4945 treatment. CX-4945 serum levels were determined at various time points. Flow cytometry of bone marrow and spleen cells was performed to analyze CX-4945-induced effects on tumor cell proliferation and distribution in B-ALL engrafted mice. ALL cells were enriched and characterized by targeted RNA sequencing. In vitro, B-ALL cell lines SEM, RS4;11 and NALM-6 were incubated with CX-4945 and gene expression of apoptosis regulators BCL6 and BACH2 was determined. RESULTS: In B-ALL-engrafted mice, overall tumor cell proliferation and distribution was not significantly influenced by CK2 inhibition. CX-4945 was detectable in serum during therapy and serum levels declined rapidly after cessation of CX-4945. While overall proliferation was not affected, early bone marrow and spleen blast frequencies seemed reduced after CK2 inhibition. Gene expression analyses revealed reduced expression of anti-apoptotic oncogene BCL6 in bone marrow blasts of CX-4945-treated animals. Further, BCL6 protein expression decreased in B-ALL cell lines exposed to CX-4945 in vitro. Surprisingly, levels of BCL6 opponent and tumor suppressor BACH2 also declined after prolonged incubation. Simultaneously, increased phosphorylation of direct CK2 target and tumor initiator AKT was detected at respective time points, even in initially pAKT-negative cell line NALM-6. CONCLUSIONS: The CK2 inhibitor CX-4945 has limited clinical effects in an in vivo B-ALL xenograft model when applied as a single drug over a six day period. However, gene expression in B-ALL cells was altered and suggested effects on apoptosis via downregulation of BCL6. Unexpectedly, the BCL6 opponent BACH2 was also reduced. Interactions and regulation loops have to be further evaluated.


Assuntos
Naftiridinas/administração & dosagem , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Medições Luminescentes , Camundongos , Naftiridinas/farmacocinética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
18.
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
19.
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
20.
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
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