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2.
Gene ; 714: 143985, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330236

RESUMO

In all eukaryotes, the response to heat stress (HS) is dependent on the activity of HS transcription factors (Hsfs). Plants contain a large number of Hsfs, however, only members of the HsfA1 subfamily are considered as master regulators of stress response and thermotolerance. In Solanum lycopersicum, among the four HsfA1 members, only HsfA1a has been proposed to possess a master regulator function. We performed a comparative analysis of HsfA1a, HsfA1b, HsfA1c and HsfA1e at different levels of regulation and function. HsfA1a is constitutively expressed under control and stress conditions, while the other members are induced in specific tissues and stages of HS response. Despite that all members are localized in the nucleus when expressed in protoplasts, only HsfA1a shows a wide range of basal activity on several HS-induced genes. In contrast, HsfA1b, HsfA1c, and HsfA1e show only high activity for specific subsets of genes. Domain swapping mutants between HsfA1a and HsfA1c revealed that the variation in that transcriptional transactivation activity is due to differences in the DNA binding domain (DBD). Specifically, we identified a conserved arginine (R107) residue in the turn of ß3 and ß4 sheet in the C-terminus of the DBD of HsfA1a that is highly conserved in plant HsfA1 proteins, but is replaced by leucine and cysteine in tomato HsfA1c and HsfA1e, respectively. Although not directly involved in DNA interaction, R107 contributes to DNA binding and consequently the activity of HsfA1a. Thus, we demonstrate that this variation in DBD in part explains the functional diversification of tomato HsfA1 members.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Choque Térmico/genética , Lycopersicon esculentum/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico/genética , Temperatura Alta , Domínios Proteicos/genética , Protoplastos/fisiologia , Temperatura Ambiente , Termotolerância/genética , Transcrição Genética/genética , Ativação Transcricional/genética
3.
Nat Commun ; 10(1): 2710, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221974

RESUMO

In animals and plants, the H3K9me3 and H3K27me3 chromatin silencing marks are deposited by different protein machineries. H3K9me3 is catalyzed by the SET-domain SU(VAR)3-9 enzymes, while H3K27me3 is catalyzed by the SET-domain Enhancer-of-zeste enzymes, which are the catalytic subunits of Polycomb Repressive Complex 2 (PRC2). Here, we show that the Enhancer-of-zeste-like protein Ezl1 from the unicellular eukaryote Paramecium tetraurelia, which exhibits significant sequence and structural similarities with human EZH2, catalyzes methylation of histone H3 in vitro and in vivo with an apparent specificity toward K9 and K27. We find that H3K9me3 and H3K27me3 co-occur at multiple families of transposable elements in an Ezl1-dependent manner. We demonstrate that loss of these histone marks results in global transcriptional hyperactivation of transposable elements with modest effects on protein-coding gene expression. Our study suggests that although often considered functionally distinct, H3K9me3 and H3K27me3 may share a common evolutionary history as well as a common ancestral role in silencing transposable elements.


Assuntos
Elementos de DNA Transponíveis/genética , Inativação Gênica , Histonas/genética , Paramecium tetraurellia/genética , Complexo Repressor Polycomb 2/metabolismo , Metilação de DNA , Processamento de Proteína Pós-Traducional/genética , Ativação Transcricional/genética
4.
Braz J Med Biol Res ; 52(7): e8381, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31241714

RESUMO

Experiments were conducted to determine if the follicle-stimulating hormone (FSH) receptor binding inhibitor (FRBI) impacts the expression levels of AT-rich interactive domain-containing protein 1A (ARID1A) and phosphatase and tensin homolog (PTEN) in ovaries and blood, as well as expressions of follicle-stimulating hormone cognate receptor (FSHR) gene and proteins. Mice in FRBI-10, FRBI-20, FRBI-30, and FRBI-40 groups were intramuscularly injected with 10, 20, 30, and 40 mg FRBI/kg, respectively, for five consecutive days. Western blotting and qRT-PCR were utilized to determine expression levels of ARID1A and PTEN proteins and mRNAs. Serum ARID1A and PTEN concentrations of the FRBI-40 group were higher than the control group (CG) and FSH group (P<0.05). FSHR mRNA levels of FRBI-20, FRBI-30, and FRBI-40 groups were lower than that of CG and FSH groups on day 15 (P<0.05 or P<0.01). Expression levels of FSHR proteins of FRBI-30 and FRBI-40 groups were lower than those of CG and FSH groups (P<0.05). Levels of ARID1A and PTEN proteins of the FRBI-30 group were greater than CG on days 20 and 30 (P<0.05). FRBI doses had significant positive correlations to levels of ARID1A and PTEN proteins. Additionally, ARID1A and PTEN had negative correlations to FSHR mRNAs and proteins. A high dose of FRBI could promote the expression levels of ARID1A and PTEN proteins in ovarian tissues. FRBI increased serum concentrations of ARID1A and PTEN. However, FRBI depressed expression levels of FSHR mRNAs and proteins in mouse ovaries.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Hormônio Foliculoestimulante/metabolismo , Proteínas Nucleares/sangue , Neoplasias Ovarianas/metabolismo , PTEN Fosfo-Hidrolase/sangue , Receptores do FSH/antagonistas & inibidores , Animais , Western Blotting , Proteínas de Ligação a DNA/sangue , Feminino , Camundongos , Proteínas Nucleares/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Ativação Transcricional/genética , Regulação para Cima
5.
Int J Mol Sci ; 20(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083458

RESUMO

To appraise how evolutionary processes, such as gene duplication and loss, influence an organism's xenobiotic sensitivity is a critical question in toxicology. Of particular importance are gene families involved in the mediation of detoxification responses, such as members of the nuclear receptor subfamily 1 group I (NR1I), the pregnane X receptor (PXR), and the constitutive androstane receptor (CAR). While documented in multiple vertebrate genomes, PXR and CAR display an intriguing gene distribution. PXR is absent in birds and reptiles, while CAR shows a tetrapod-specific occurrence. More elusive is the presence of PXR and CAR gene orthologs in early branching and ecologically-important Chondrichthyes (chimaeras, sharks and rays). Therefore, we investigated various genome projects and use them to provide the first identification and functional characterization of a Chondrichthyan PXR from the chimaera elephant shark (Callorhinchus milii, Holocephali). Additionally, we substantiate the targeted PXR gene loss in Elasmobranchii (sharks and rays). Compared to other vertebrate groups, the chimaera PXR ortholog displays a diverse expression pattern (skin and gills) and a unique activation profile by classical xenobiotic ligands. Our findings provide insights into the molecular landscape of detoxification mechanisms and suggest lineage-specific adaptations in response to xenobiotics in gnathostome evolution.


Assuntos
Elasmobrânquios/classificação , Elasmobrânquios/genética , Evolução Molecular , Redes Reguladoras de Genes , Filogenia , Receptor de Pregnano X/genética , Animais , Células COS , Cercopithecus aethiops , Genes Reporter , Inativação Metabólica/genética , Luciferases/metabolismo , Receptor de Pregnano X/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Sintenia/genética , Ativação Transcricional/genética
6.
Int J Mol Sci ; 20(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035388

RESUMO

Transactivation of p21 (cyclin-dependent kinase inhibitor 1A, CDKN1A) is closely related to the recruitment of transcription cofactors at the p53 responsive elements (p53REs) in its promoter region. Human chromatin remodeling enzyme INO80 can be recruited to the p53REs of p21 promoter and negatively regulates p21. As one of the key subunits of the INO80 complex, YY1 has also been confirmed to bind to the p53RE sites of p21 promoter. Importantly, YY1 was recently reported to be bound and stabilized by BCCIP (BRCA2 and CDKN1A-interacting protein). Therefore, we hypothesized that the YY1/BCCIP complex plays an important role in regulating the transactivation of p21. Here we present evidence that the YY1/BCCIP complex coordinatively regulates p53RE-mediated p21 transactivation. We first confirmed the cross-interaction between YY1, BCCIP, and p53, suggesting an intrinsic link between three proteins in the regulation of p21 transcription. In dual luciferase assays, YY1 inhibited p53RE-mediated luciferase activity, whereas BCCIP revealed the opposite effect. More interestingly, the region 146-270 amino acids of YY1, which bound to BCCIP, increased p53-mediated luciferase activity, indicating the complexity of the YY1/BCCIP complex in co-regulating p21 transcription. Further in-depth research confirmed the co-occupancy of YY1/BCCIP with p53 at the p53RE-proximal region of p21. Lentiviral-mediated knockdown of BCCIP inhibited the recruitment of p53 and YY1 at the p53RE proximal region of p21; however, this phenomenon was reversed by expressing exogenous YY1, suggesting the collaborative regulation of YY1/BCCIP complex in p53RE-mediated p21 transcription. These data provide new insights into the transcriptional regulation of p21 by the YY1/BCCIP complex.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fator de Transcrição YY1/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Células HCT116 , Humanos , Proteínas Nucleares/genética , Ativação Transcricional/genética , Ativação Transcricional/fisiologia , Fator de Transcrição YY1/genética
7.
Pol J Microbiol ; 68(1): 43-50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050252

RESUMO

Several biotypes of the Gram-negative bacterium Serratia marcescens produce the tri-pyrole pigment and secondary metabolite prodigiosin. The biological activities of this pigment have therapeutic potential. For over half a century it has been known that biosynthesis of prodi giosin is inhibited when bacteria are grown at elevated temperatures, yet the fundamental mechanism underlying this thermoregulation has not been characterized. In this study, chromosomal and plasmid-borne luxCDABE transcriptional reporters revealed reduced transcription of the prodigiosin biosynthetic operon at 37°C compared to 30°C indicating transcriptional control of pigment production. Moreover, induced expression of the prodigiosin biosynthetic operon at 37°C was able to produce pigmented colonies and cultures demonstrating that physiological conditions at 37°C allow prodigiosin production and indicating that post-transcriptional control is not a major contributor to the thermoregulation of prodigiosin pigmentation. Genetic experiments support the model that the HexS transcription factor is a key contributor to thermoregulation of pigmentation, whereas CRP plays a minor role, and a clear role for EepR and PigP was not observed. Together, these data indicate that thermoregulation of prodigiosin production at elevated temperatures is controlled largely, if not exclusively, at the transcriptional level.Several biotypes of the Gram-negative bacterium Serratia marcescens produce the tri-pyrole pigment and secondary metabolite prodigiosin. The biological activities of this pigment have therapeutic potential. For over half a century it has been known that biosynthesis of prodi giosin is inhibited when bacteria are grown at elevated temperatures, yet the fundamental mechanism underlying this thermoregulation has not been characterized. In this study, chromosomal and plasmid-borne luxCDABE transcriptional reporters revealed reduced transcription of the prodigiosin biosynthetic operon at 37°C compared to 30°C indicating transcriptional control of pigment production. Moreover, induced expression of the prodigiosin biosynthetic operon at 37°C was able to produce pigmented colonies and cultures demonstrating that physiological conditions at 37°C allow prodigiosin production and indicating that post-transcriptional control is not a major contributor to the thermoregulation of prodigiosin pigmentation. Genetic experiments support the model that the HexS transcription factor is a key contributor to thermoregulation of pigmentation, whereas CRP plays a minor role, and a clear role for EepR and PigP was not observed. Together, these data indicate that thermoregulation of prodigiosin production at elevated temperatures is controlled largely, if not exclusively, at the transcriptional level.


Assuntos
Regulação Bacteriana da Expressão Gênica/genética , Prodigiosina/biossíntese , Serratia marcescens/genética , Serratia marcescens/metabolismo , Fatores de Transcrição/genética , Transcrição Genética/genética , Aciltransferases/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Temperatura Alta , Oxirredutases/genética , Ativação Transcricional/genética
8.
Anal Chim Acta ; 1067: 129-136, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31047144

RESUMO

BCR/ABLp210 fusion gene, the characteristic biomarker of chronic myelogenous leukemia (CML), contains two different transcription isoforms, e13a2 and e14a2, which lead to differences in the pathological features and response to targeted drug. At present, there is short of simple and fast technology to distinguish these two transcript isoforms. In this paper, RNA fusion-triggered rolling circle amplification (RF-RCA) strategy was developed to distinguish e13a2 and e14a2 transcripts directly from RNA extraction in one step. The simultaneous binding of dumbbell template and corresponding primer with target fused RNA can induce their proximal hybridization and trigger the RCA to produce lots of tandem repeat G-quadruplexes sequences for real time fluorescence readout with the interaction of Thioflavin T and G-quadruplex. The proposed strategy can detect as low as 0.1 aM target and discriminate e13a2 (0.01%) and e14a2 (0.1%) transcript isoforms directly from complex genomic RNA extraction, proving high sensitivity and specificity. Furthermore, the RF-RNA was successfully applied to analyze BCR/ABLp210 isoforms from clinical samples for accurately molecular subtyping and monitoring the response of imatinib treatment. The developed RF-RCA strategy presented an ultrasensitive, accurate and pragmatic toolbox to simple and rapid discriminate BCR/ABLp210 fusion isoforms for promoting clinical research and personalized treatment of CML.


Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Técnicas de Amplificação de Ácido Nucleico , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Isoformas de Proteínas/genética , Ativação Transcricional/genética
9.
Biochim Biophys Acta Rev Cancer ; 1872(1): 11-23, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31034924

RESUMO

The ubiquitous family of AP-1 dimeric transcription complexes is involved in virtually all cellular and physiological functions. It is paramount for cells to reprogram gene expression in response to cues of many sorts and is involved in many tumorigenic processes. How AP-1 controls gene transcription has largely remained elusive till recently. The advent of the "omics" technologies permitting genome-wide studies of transcription factors has however changed and improved our view of AP-1 mechanistical actions. If these studies confirm that AP-1 can sometimes act as a local transcriptional switch operating in the vicinity of transcription start sites (TSS), they strikingly indicate that AP-1 principally operates as a remote command binding to distal enhancers, placing chromatin architecture dynamics at the heart of its transcriptional actions. They also unveil novel constraints operating on AP-1, as well as novel mechanisms used to regulate gene expression via transcription-pioneering-, chromatin-remodeling- and chromatin accessibility maintenance effects.


Assuntos
Complexos Multiproteicos/genética , Fator de Transcrição AP-1/genética , Transcrição Genética , Ativação Transcricional/genética , Sítios de Ligação/genética , Núcleo Celular/genética , Montagem e Desmontagem da Cromatina/genética , Humanos , Complexos Multiproteicos/química , Fator de Transcrição AP-1/química , Sítio de Iniciação de Transcrição
10.
Biomed Pharmacother ; 114: 108683, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30947016

RESUMO

OBJECTIVE: This study is conducted to explore the role of microRNA-223 (miR-223) in brain injury and apoptosis of hippocampal neurons through the NLRP3-Caspase-1 signaling pathway in febrile seizure (FS) rats. METHODS: The models of FS were induced in rats by hot water-bath, which were stereotactically injected with miR-223 mimics and mimics negative control (NC) to perturb the expression of miR-223. A series of experiments was conducted to find out the potential mechanisms of miR-223 on convulsion attack, learning and memory ability, pathological injury of hippocampal neurons, inflammatory injury, apoptosis of hippocampal neurons in FS rats. Besides, the targeting relationship between miR-223 and NLRP3 was also verified. RESULTS: Low expression of miR-223 was found in hippocampus tissues of FS rats. Up-regulation of miR-223 alleviated convulsion attack and improved learning and memory ability, while inhibiting pathological injury of hippocampal neurons and inflammatory injury in FS rats. Up-regulation of miR-223 promoted the survival of hippocampal neurons and inhibited their apoptosis in FS rats. MiR-223 inhibited the activation of NLRP3-Caspase-1 signaling pathway in hippocampus tissues of FS rats by inhibiting NLRP3. CONCLUSION: The inhibited expression of miR-223 after FS may participate in the activation of the NLRP3-Caspase-1 signaling pathway, resulting in brain injury and apoptosis of hippocampal neurons in rat models of FS.


Assuntos
Apoptose/genética , Lesões Encefálicas/genética , Caspase 1/genética , MicroRNAs/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Convulsões Febris/genética , Regulação para Cima/genética , Animais , Lesões Encefálicas/patologia , Hipocampo/patologia , Aprendizagem/fisiologia , Memória/fisiologia , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Convulsões/genética , Convulsões/patologia , Transdução de Sinais/genética , Ativação Transcricional/genética
11.
Horm Metab Res ; 51(4): 248-255, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31022740

RESUMO

The objective of the study is the functional characterization of a novel POU1F1 c.605delC mutation in combined pituitary hormone deficiency (CPHD) and to report the clinical and genetic details of 160 growth hormone deficiency patients. Screening of GH1, GHRHR, POU1F1, PROP1, and HESX1 genes by Sanger sequencing was carried out in 160 trios and 100 controls followed by characterization of the POU1F1 c.605delC mutation by expression studies including site directed mutagenesis, co-transfection, protein degradation, and luciferase assays to compare the wild type and mutant POU1F1. In vitro studies showed that the POU1F1 c.605delC mutation codes for a truncated protein with reduced transactivation capacity on its downstream effectors, viz., growth hormone (GH) and prolactin (PRL) causing severe CPHD. Experiments using different protease inhibitors reveal rescue of the protein upon blockage of the lysosomal pathway that might be useful in novel drug designing using targeted approach thereby maintaining the milieu and preventing/delaying the disease. The study provides an insight into the disease causing mechanism of POU1F1 c.605delC mutation identified in a CPHD child with severe short stature and failure to thrive. It also shows mutation effect on the expression, function and turnover of protein and highlights mechanistic details by which these potent regulators may operate.


Assuntos
Nanismo Hipofisário/genética , Testes Genéticos , Mutação/genética , Fator de Transcrição Pit-1/genética , Criança , Feminino , Hormônio do Crescimento Humano/genética , Humanos , Hipopituitarismo/genética , Masculino , Proteínas Mutantes/metabolismo , Taxa de Mutação , Prolactina/genética , Domínios Proteicos , Proteólise , Fator de Transcrição Pit-1/química , Ativação Transcricional/genética
12.
BMC Cancer ; 19(1): 381, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023247

RESUMO

BACKGROUND: Salinomycin is a monocarboxylic polyether antibiotic and is a potential chemotherapy drug. Our previous studies showed that salinomycin inhibited cell growth and targeted CSCs in prostate cancer. However, the precise target of salinomycin action is unclear. METHODS: In this work, we analyzed and identified differentially expressed genes (DEGs) after treatment with or without salinomycin using a gene expression microarray in vitro (PC-3 cells) and in vivo (NOD/SCID mice xenograft model generated from implanted PC-3 cells). Western blotting and immunohistochemical staining were used to analyze the expression of ATP2A3 and endoplasmic reticulum (ER) stress biomarkers. Flow cytometry was used to analyze the cell cycle, apoptosis and intracellular Ca2+ concentration. RESULTS: A significantly upregulated gene, ATPase sarcoplasmatic/endoplasmatic reticulum Ca2+ transporting 3 (ATP2A3), was successfully identified. In subsequent studies, we found that ATP2A3 overexpression could trigger ER stress and exert anti-cancer effects in PC-3 and DU145 cells. ATP2A3 was slightly expressed, but the ER stress biomarkers showed strong staining in prostate cancer tissues. We also found that salinomycin could trigger ER stress, which might be related to ATP2A3-mediated Ca2+ release in PC-3 cells. Furthermore, we found that salinomycin-triggered ER stress could promote apoptosis and thus exert anti-cancer effects in prostate cancer cells. CONCLUSION: This study demonstrates that ATP2A3 might be one of the potential targets for salinomycin, which can inhibit Ca2+ release and trigger ER stress to exert anti-cancer effects.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Piranos/administração & dosagem , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Nat Cell Biol ; 21(5): 627-639, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30988423

RESUMO

How disseminated tumour cells engage specific stromal components in distant organs for survival and outgrowth is a critical but poorly understood step of the metastatic cascade. Previous studies have demonstrated the importance of the epithelial-mesenchymal transition in promoting the cancer stem cell properties needed for metastasis initiation, whereas the reverse process of mesenchymal-epithelial transition is required for metastatic outgrowth. Here we report that this paradoxical requirement for the simultaneous induction of both mesenchymal-epithelial transition and cancer stem cell traits in disseminated tumour cells is provided by bone vascular niche E-selectin, whose direct binding to cancer cells promotes bone metastasis by inducing mesenchymal-epithelial transition and activating Wnt signalling. E-selectin binding activity mediated by the α1-3 fucosyltransferases Fut3/Fut6 and Glg1 are instrumental to the formation of bone metastasis. These findings provide unique insights into the functional role of E-selectin as a component of the vascular niche critical for metastatic colonization in bone.


Assuntos
Neoplasias Ósseas/genética , Selectina E/genética , Fucosiltransferases/genética , Metástase Neoplásica/genética , Neoplasias/genética , Animais , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Humanos , Camundongos , Metástase Neoplásica/patologia , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Receptores de Fatores de Crescimento de Fibroblastos/genética , Sialoglicoproteínas/genética , Transdução de Sinais/genética , Nicho de Células-Tronco/genética , Ativação Transcricional/genética , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
14.
BMC Plant Biol ; 19(1): 154, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023225

RESUMO

BACKGROUND: Trihelix transcription factors (TTFs) are photoresponsive proteins that have a representative three-helix structure (helix-loop-helix-loop-helix). Members of this gene family have been reported to play roles in many plant processes. RESULTS: In this study, we performed a functional and evolutionary analysis of the TTFs in Moso bamboo (Phyllostachys edulis). A total of 35 genes were identified and grouped into five subfamilies (GT-1, GT-γ, GT-2, SIP1 and SH4) according to their structural properties. Gene structure analysis showed that most genes in the PeTTF family had fewer introns. A unique motif (Motif 16) to the GT-γ subfamily was identified by conserved motif analysis. Promoter analysis revealed various cis-acting elements related to plant growth and development, abiotic and biotic stresses, and phytohormone responses. Data for the 35 Moso bamboo TTF genes were used to generate heat maps, which indicated that these genes were expressed in different tissues or developmental stages. Most of the TTF genes identified here had high expression in leaves and panicles according to the expression profile analysis. The expression levels of the TTF members in young leaves were studied using quantitative real-time PCR to determine their tissue specificity and stress-related expression patterns to help functionally characterize individual members. CONCLUSIONS: The results indicated that members of the TTF gene family may be involved in plant responses to stress conditions. Additionally, PeTTF29 was shown to be located in the nucleus by subcellular localization analysis and to have transcriptional activity in a transcriptional activity assay. Our research provides a comprehensive summary of the PeTTF gene family, including functional and evolutionary perspectives, and provides a basis for functionally characterizing these genes.


Assuntos
Evolução Molecular , Poaceae/genética , Fatores de Transcrição/genética , Acetatos/farmacologia , Arabidopsis/genética , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sequência Conservada , Ciclopentanos/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Genes de Plantas , Motivos de Nucleotídeos , Oryza/genética , Oxilipinas/farmacologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
15.
BMB Rep ; 52(4): 227-238, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30885290

RESUMO

GROWTH-REGULATING FACTORs (GRFs) are sequencepecific DNA-binding transcription factors that regulate various aspects of plant growth and development. GRF proteins interact with a transcription cofactor, GRF-INTERACTING FACTOR (GIF), to form a functional transcriptional complex. For its activities, the GRF-GIF duo requires the SWITCH2/ SUCROSE NONFERMENTING2 chromatin remodeling complex. One of the most conspicuous roles of the duo is conferring the meristematic potential on the proliferative and formative cells during organogenesis. GRF expression is post-transcriptionally down-regulated by microRNA396 (miR396), thus constructing the GRF-GIF-miR396 module and fine-tuning the duo's action. Since the last comprehensive review articles were published over three years ago, many studies have added further insight into its action and elucidated new biological roles. The current review highlights recent advances in our understanding of how the GRF-GIF-miR396 module regulates plant growth and development. In addition, I revise the previous view on the evolutionary origin of the GRF gene family. [BMB Reports 2019; 52(4): 227-238].


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Desenvolvimento Vegetal/fisiologia , Evolução Biológica , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , MicroRNAs/genética , Desenvolvimento Vegetal/genética , Plantas/metabolismo , Receptores de Fatores de Crescimento/fisiologia , Transativadores , Fatores de Transcrição/metabolismo , Ativação Transcricional/genética , Ativação Transcricional/fisiologia
16.
Hum Antibodies ; 27(2): 129-134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856107

RESUMO

BACKGROUND: ID-1 gene codes for a helix-loop-helix (HLH) protein that inhibits the DNA binding and transcriptional activation function of these proteins. METHODS: We analyzed ID-1 expression in microarray and RNA Sequencing databases as well as 61 breast cancer tissues compared with adjacent non-cancerous tissues (ANCTs). RESULTS: Expression analysis of ID-1 gene in two microarray datasets and RNA sequencing data showed down-regulation of ID-1 in tumoral tissues compared with normal tissues. However, ID-1 expression analysis in tumoral tissues and ANCTs obtained from 61 patients revealed its over-expression in tumoral tissues. A negative association was detected between ID-1 expression levels and ER status. CONCLUSION: ID-1 expression may be implicated in the pathogenesis of breast cancer especially in patient with ER negative status.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Regulação para Baixo/genética , Feminino , Sequências Hélice-Alça-Hélice/genética , Humanos , Pessoa de Meia-Idade , Análise de Sequência de RNA/métodos , Ativação Transcricional/genética
17.
J Biosci ; 44(1)2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30837365

RESUMO

DNA methylation is an important epigenetic modification that governs transcriptional regulation. The methylation mark is read by a special class of proteins called methyl-CpG-binding domain proteins. The role of DNA methylation has been found in X-chromosome inactivation, genomic imprinting, transposon silencing, and self-incompatibility. Recently, remodeling of global DNA methylation was demonstrated in Arabidopsis during low phosphate availability. The present study reports that AtMBD4 gene of Arabidopsis negatively regulates phosphate starvation. The T-DNA insertion mutation at the AtMBD4 locus exhibited altered root architecture as compared to wild-type plants. Using microarray hybridization and analysis, an increased transcript accumulation of 242 genes was observed in the mutant. Many of these genes were related to phosphate transporters and transcription factors, involved in phosphate starvation response. Comparison of data of atmbd4 mutant with publicly available microarray data of phosphate starvation response indicated the role of AtMBD4 protein in phosphate starvation response. Further, promoter analysis of up-regulated genes suggested that cis-regulatory elements like MBS, W-box, and B1BS are more prominent in the promoters of up-regulated genes. Upon performing a methylation-specific PCR, a decreased DNA methylation in the promoter regions of up-regulated genes was observed. The accumulation of anthocyanin and inorganic phosphate in the atmbd4 mutant was found to be higher than the wild-type plant. Altered root morphology, up-regulation of phosphate starvation-induced genes in atmbd4 mutant suggests that AtMBD4 negatively regulates the phosphate starvation response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Metilação de DNA/genética , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética/genética , Fosfatos/metabolismo , Ativação Transcricional/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , DNA Bacteriano/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Mutagênese Insercional/genética , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas
18.
Arch Virol ; 164(5): 1393-1404, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30877452

RESUMO

Many transcription factors are encoded by DNA viruses and retroviruses due to their regulatory roles in gene expression in the host cell. However, no transcriptional regulator has been identified in any reovirus. Here, a non-structural protein, NS31, encoded by grass carp reovirus genomic segment S7 was characterized. The NS31 protein is predicted to contain a helix-turn-helix (HTH)-like domain and a C-terminal acidic α-helix motif. In yeast, a fusion protein composed of the Gal4-BD domain and NS31 (BD-NS31) was able to activate the expression of reporter genes (Gal1/MEL1 promoter) without the Gal4-AD domain. We also found that NS31 activated the reporter genes in a BD-dependent manner, and both the C- and N-termini contribute to the activation function of NS31. Furthermore, NS31 homologues from other aquareoviruses were also shown to possess a similar transcriptional activation function in yeast. Thus, the aquareovirus NS31 protein appears to act as a transcriptional regulatory protein, the first one identified in a member of the family Reoviridae.


Assuntos
Carpas/virologia , Reoviridae/genética , Ativação Transcricional/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Regulação Viral da Expressão Gênica/genética , Genes Reporter/genética , Células HeLa , Humanos , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae/genética
19.
Int J Mol Sci ; 20(5)2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30836695

RESUMO

Stripe rust, caused by the pathogen Puccinia striiformis f. sp. tritici (Pst), is an important fungal foliar disease of wheat (Triticum aestivum). To study the mechanism underlying the defense of wheat to Pst, we used the next-generation sequencing and isobaric tags for relative and absolute quantification (iTRAQ) technologies to generate transcriptomic and proteomic profiles of seedling leaves at different stages under conditions of pathogen stress. By conducting comparative proteomic analysis using iTRAQ, we identified 2050, 2190, and 2258 differentially accumulated protein species at 24, 48, and 72 h post-inoculation (hpi). Using pairwise comparisons and weighted gene co-expression network analysis (WGCNA) of the transcriptome, we identified a stress stage-specific module enriching in transcription regulator genes. The homologs of several regulators, including splicing and transcription factors, were similarly identified as hub genes operating in the Pst-induced response network. Moreover, the Hsp70 protein were predicted as a key point in protein⁻protein interaction (PPI) networks from STRING database. Taking the genetics resistance gene locus into consideration, we identified 32 induced proteins in chromosome 1BS as potential candidates involved in Pst resistance. This study indicated that the transcriptional regulation model plays an important role in activating resistance-related genes in wheat responding to Pst stress.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Proteoma/genética , Transcriptoma/genética , Triticum/genética , Basidiomycota/patogenicidade , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes/genética , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/microbiologia , Proteômica/métodos , Plântula/genética , Ativação Transcricional/genética , Triticum/crescimento & desenvolvimento , Triticum/microbiologia
20.
Biomed Res Int ; 2019: 3702783, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30834261

RESUMO

Increased metabolism accelerates local acid production in cancer tissue. The mechanisms eliminating acidic waste products from human colon cancer tissue represent promising therapeutic targets for pharmacological manipulation in order to improve prognosis for the increasing number of patients with colon cancer. We sampled biopsies of human colonic adenocarcinomas and matched normal colon tissue from patients undergoing colon cancer surgery. We measured steady-state intracellular pH and rates of net acid extrusion in freshly isolated human colonic crypts based on fluorescence microscopy. Net acid extrusion was almost entirely (>95%) Na+-dependent. The capacity for net acid extrusion was increased and steady-state intracellular pH elevated around 0.5 in crypts from colon cancer tissue compared with normal colon tissue irrespective of whether they were investigated in the presence or absence of CO2/HCO3 -. The accelerated net acid extrusion from the human colon cancer tissue was sensitive to the Na+/H+-exchange inhibitor cariporide. We conclude that enhanced net acid extrusion via Na+/H+-exchange elevates intracellular pH in human colon cancer tissue.


Assuntos
Ácidos/metabolismo , Neoplasias do Colo/genética , Trocadores de Sódio-Hidrogênio/genética , Ácidos/química , Bicarbonatos/metabolismo , Dióxido de Carbono/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/ultraestrutura , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Guanidinas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Íons/metabolismo , Masculino , Microscopia de Fluorescência , Trocadores de Sódio-Hidrogênio/metabolismo , Sulfonas/farmacologia , Ativação Transcricional/genética
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