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1.
Genes Dev ; 36(1-2): 17-22, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34916303

RESUMO

Eukaryotic cells maintain an optimal level of mRNAs through unknown mechanisms that balance RNA synthesis and degradation. We found that inactivation of the RNA exosome leads to global reduction of nascent mRNA transcripts, and that this defect is accentuated by loss of deposition of histone variant H2A.Z. We identify the mRNA for the sirtuin deacetylase Hst3 as a key target for the RNA exosome that mediates communication between RNA degradation and transcription machineries. These findings reveal how the RNA exosome and H2A.Z function together to control a deacetylase, ensuring proper levels of transcription in response to changes in RNA degradation.


Assuntos
Complexo Multienzimático de Ribonucleases do Exossomo , Sirtuínas , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Histonas/genética , Histonas/metabolismo , Homeostase/genética , RNA Mensageiro/genética , Sirtuínas/genética , Sirtuínas/metabolismo
2.
Am J Hum Genet ; 111(2): 383-392, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38242117

RESUMO

The C9orf72 hexanucleotide repeat expansion (HRE) is a common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The inheritance is autosomal dominant, but a high proportion of subjects with the mutation are simplex cases. One possible explanation is de novo expansions of unstable intermediate-length alleles (IAs). Using haplotype sharing trees (HSTs) with the haplotype analysis tool kit (HAPTK), we derived majority-based ancestral haplotypes of HRE samples and discovered that IAs containing ≥18-20 repeats share large haplotypes in common with the HRE. Using HSTs of HRE and IA samples, we demonstrate that the longer IA haplotypes are largely indistinguishable from HRE haplotypes and that several ≥18-20 IA haplotypes share over 5 Mb (>600 markers) haplotypes in common with the HRE haplotypes. These analysis tools allow physical understanding of the haplotype blocks shared with the majority-based ancestral haplotype. Our results demonstrate that the haplotypes with longer IAs belong to the same pool of haplotypes as the HRE and suggest that longer IAs represent potential premutation alleles.


Assuntos
Esclerose Lateral Amiotrófica , Proteína C9orf72 , Árvores , Humanos , Alelos , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Expansão das Repetições de DNA/genética , Haplótipos/genética , Receptores Proteína Tirosina Quinases/genética , Árvores/genética
3.
Mol Cell Proteomics ; 23(1): 100695, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38101750

RESUMO

In response to genotoxic stress, cells evolved with a complex signaling network referred to as the DNA damage response (DDR). It is now well established that the DDR depends upon various posttranslational modifications; among them, ubiquitylation plays a key regulatory role. Here, we profiled ubiquitylation in response to the DNA alkylating agent methyl methanesulfonate (MMS) in the budding yeast Saccharomyces cerevisiae using quantitative proteomics. To discover new proteins ubiquitylated upon DNA replication stress, we used stable isotope labeling by amino acids in cell culture, followed by an enrichment of ubiquitylated peptides and LC-MS/MS. In total, we identified 1853 ubiquitylated proteins, including 473 proteins that appeared upregulated more than 2-fold in response to MMS treatment. This enabled us to localize 519 ubiquitylation sites potentially regulated upon MMS in 435 proteins. We demonstrated that the overexpression of some of these proteins renders the cells sensitive to MMS. We also assayed the abundance change upon MMS treatment of a selection of yeast nuclear proteins. Several of them were differentially regulated upon MMS treatment. These findings corroborate the important role of ubiquitin-proteasome-mediated degradation in regulating the DDR.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteoma/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ubiquitinação , Proteínas de Saccharomyces cerevisiae/metabolismo , Dano ao DNA , Reparo do DNA
4.
Xenotransplantation ; 31(2): exen12855, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38602029

RESUMO

Carbohydrate-antigens widely existed on glycoproteins and glycosphingolipids of all mammalian cells play a crucial role in self-defense and immunity. Xeno-reactive antibodies included in natural human sera play a protecting role in an acute phase-rejection of xenotransplantation. In this study, we investigated the effect of an alteration of glycosylation-pattern, caused by human sialyltransferases such as hST3Gal II or hST6GalNAc IV, on human serum mediated cytotoxicity in pig kidney PK15 cells. From LDH cytotoxicity assay, cytotoxicity to human serum was significantly increased in hST3Gal II and hST6GalNAc IV-transfected PK15 cells, as compared to the control. In the hST6Gal I-carrying cells, the cytotoxicity to human serum was rather decreased. Moreover, flow cytometry analysis revealed that an alteration of pig glycosylation-pattern by hST3Gal II or hST6GalNAc IV influences on a binding of human IgM or IgG, respectively, in pig kidney cells, regardless of Gal antigen alteration. Finally, we found that hST6GalNAc IV contributed to increase of terminal disialylated tetrasaccharide structure, disialyl T antigen, as evidenced by increase of the MAL II lectin binding capacity in the hST6GalNAc IV-transfected PK15 cells, compared with control. Therefore, our results suggest that carbohydrate antigens, such as disialyl T antigen, newly synthesized by the ST3Gal II- and ST6GalNAc IV are potentially believed to be new xeno-reactive elements.


Assuntos
Sialiltransferases , Transplante Heterólogo , beta-Galactosídeo alfa-2,3-Sialiltransferase , Animais , Humanos , Antígenos Virais de Tumores , Carboidratos , Mamíferos/metabolismo , Sialiltransferases/genética , Sialiltransferases/química , Sialiltransferases/metabolismo , Suínos
5.
Glycoconj J ; 40(6): 621-630, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37921922

RESUMO

In this study we observed that human GD1c/GT1a/GQ1b synthase (hST8Sia V) is particularly expressed in human glioblastoma cells. To address the mechanism regulating human glioblastoma-specific gene expression of the hST8Sia V, after the transcription start site (TSS) was identified by the 5'-rapid amplification of cDNA end with total RNA from human glioblastoma U87MG cells, the 5'-flanking region (2.5 kb) of the hST8Sia V gene was isolated and its promoter activity was examined. By luciferase reporter assay, this 5'-flanking region revealed strong promoter activity in only U-87MG cells, but not in other tissue-derived cancer cells. 5'-deletion mutant analysis showed that the region from -1140 to -494 is crucial for transcription of the hST8Sia V gene in U87MG cells. This region contains the activator protein-1 (AP-1) binding site, the main target of the c-Jun N-terminal kinase (JNK) downstream. The AP-1 binding site at -1043/-1037 was proved to be indispensable for the hST8Sia V gene-specific expression in U87MG cells by site-directed mutagenesis. Moreover, the transcriptional activation of hST8Sia V gene in U87MG cells was strongly inhibited by a specific JNK inhibitor, SP600125. These results suggest that the hST8Sia V gene-specific expression in U87MG cells is controlled by JNK/AP-1 signaling pathway.


Assuntos
Glioblastoma , Humanos , Glioblastoma/genética , Fator de Transcrição AP-1/genética , Regiões Promotoras Genéticas/genética , Ativação Transcricional
6.
Fungal Genet Biol ; 159: 103656, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34974188

RESUMO

C. glabrata is an opportunistic fungal pathogen and the second most common cause of opportunistic fungal infections in humans, that has evolved virulence factors to become a successful pathogen: strong resistance to oxidative stress, capable to adhere and form biofilms in human epithelial cells as well as to abiotic surfaces and high resistance to xenobiotics. Hst1 (a NAD+-dependent histone deacetylase), Sum1 (putative DNA binding protein) and Rfm1 (connector protein) form a complex (HRS-C) and control the resistance to oxidative stress, to xenobiotics (the antifungal fluconazole), and adherence to epithelial cells. Hst1 is functionally conserved within the Saccharomycetaceae family, Rfm1 shows a close phylogenetic relation within the Saccharomycetaceae family while Sum1 displays a distant phylogenetic relation with members of the family and is not conserved functionally. CDR1 encodes for an ABC transporter (resistance to fluconazole) negatively controlled by HRS-C, for which its binding site is located within 223 bp upstream from the ATG of CDR1. The absence of Hst1 and Sum1 renders the cells hyper-adherent, possibly due to the overexpression of AED1, EPA1, EPA22 and EPA6, all encoding for adhesins. Finally, in a neutrophil survival assay, HST1 and SUM1, are not required for survival. We propose that Sum1 in the HRS-C diverged functionally to control a set of genes implicated in virulence: adherence, resistance to xenobiotics and oxidative stress.


Assuntos
Candida glabrata , Fluconazol , Antifúngicos , Candida glabrata/genética , Fluconazol/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Humanos , Filogenia , Virulência/genética , Xenobióticos
7.
Sensors (Basel) ; 22(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36560388

RESUMO

During channel modeling for high-mobility channels, such as high-speed train (HST) channels, the velocity of the mobile radio station is assumed to be constant. However, this might not be realistic due to the dynamic movement of the train along the track. Therefore, in this paper, an enhanced Gauss-Markov mobility model with a 3D non-stationary geometry based stochastic model (GBSM) for HST in MIMO Wireless Channels is proposed. The non-isotropic scatterers within a cluster are assumed to be around the sphere in which the mobile relay station (MRS) is located. The multi-path components (MPCs) are modeled with varying velocities, whereas the mobility model is a function of time. The MPCs are represented in a death-birth cluster using the Markov process. Furthermore, the channel statistics, i.e., the space-time correlation function, the root-mean-square Doppler shift, and the quasi-stationary interval, are derived from the non-stationary model. The model shows how the quasi-stationary time increases from 0.21 to 0.451 s with a decreasing acceleration of 0.6 to 0.2 m/s2 of the HST. In addition, the impact of the distribution of the angles on the channel statistics is presented. Finally, the simulated results are compared with the measured results. Therefore, there is a close relationship between the proposed model and the measured results, and the model can be used to characterize the channel's properties.

8.
Acta Anaesthesiol Scand ; 65(7): 921-927, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33725363

RESUMO

PURPOSE: Physical impairment after critical illness is recognized as a part of the post-intensive care syndrome (PICS). About one third of intensive care unit (ICU) survivors suffer from long-term physical disability, yet the underlying pathophysiological mechanisms remain poorly understood. The pro-inflammatory alarmin, high mobility group box 1 (HMGB1), promotes muscle dysfunction in experimental models, and HMGB1 stays elevated in some patients after ICU discharge. Accordingly, we investigated the relationship between HMGB1 plasma levels and physical performance in ICU survivors. METHODS: Prospective cohort study of 100 ICU survivors from the general ICU at the Karolinska University Hospital, Sweden. Patients returned for follow up at 3 (58 patients) and 6 months (51 patients) after ICU discharge. Blood samples were collected, and a 6-minute walk test (6-MWT), a handgrip-strength test (HST), and a timed-stands test (TST) were performed. RESULTS: Compared to reference values of the different physical tests, 16% of patients underperformed at all tests at 3 months and 12% at 6 months. All test results, except hand-grip strength left, improved significantly over the follow-up period (P < .05). There was no significant association between plasma HMGB1 levels at 3 and 6 months and scores on the three tests (6-MWT, TST, and HST) (P = .50-0.69). CONCLUSION: In this follow-up study of ICU survivors, we found no significant association between plasma HMGB1 levels and physical performance. Additional follow-up studies of HMGB1 plasma levels and muscle function in ICU survivors are still warranted. EDITORIAL COMMENT: HMGB-1, a marker of cell damage and activation, is known to increase in ICU patients. In study participants at 3- to 6-month post-ICU stay, HMGB-1 levels were still elevated, although no association to the primary outcome, physical performance, was found. Mechanisms for failure to recover physical performance post-ICU remain unclear, and investigations into cause of post-intensive care syndrome need to continue. TRIAL REGISTRATIONS: ClinicalTrials.gov identifier NCT02914756.


Assuntos
Proteína HMGB1 , Estado Terminal , Seguimentos , Força da Mão , Humanos , Unidades de Terapia Intensiva , Desempenho Físico Funcional , Estudos Prospectivos , Sobreviventes
9.
Glycoconj J ; 37(6): 681-690, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33108606

RESUMO

In this study, we found that gene expression of the human ß-galactoside α2,6-sialyltransferase (hST6Gal I) was specifically increased during differentiation of human MG-63 osteoblastic cells by serum starvation (SS). In parallel, a distinct increase in binding to SNA, the α2,6-sialyl-specific lectin, was observed in serum-starved cells, as demonstrated by FACS analysis. 5'-Rapid amplification of cDNA ends analysis demonstrated that the increase of hST6Gal I transcript by SS is mediated by P1 promoter. To elucidate transcriptional regulation of hST6Gal I in SS-induced MG-63 cells, we functionally characterized the P1 promoter region of the hST6Gal I gene. The 5'-deletion analysis of P1 promoter region revealed that the 189 bp upstream region of transcription start site is critical for transcriptional activity of hST6Gal I gene in SS-induced MG-63 cells. This region contains the predicted binding sites for several transcription factors, including AREB6, FOXP1, SIX3, HNF1, YY2, and MOK2. The mutagenesis analysis for these sites and chromatin immunoprecipitation assay demonstrated that the YY2 binding site at -98 to -77 was essential for the SS-induced hST6Gal I gene expression during differentiation of MG-63 cells.


Assuntos
Antígenos CD/genética , Diferenciação Celular/genética , Osteoblastos/citologia , Sialiltransferases/genética , Transcrição Gênica , Proteínas de Ligação a DNA/genética , Proteínas do Olho/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação Enzimológica da Expressão Gênica/genética , Proteínas de Homeodomínio/genética , Humanos , Proteínas do Tecido Nervoso/genética , Osteoblastos/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Sítio de Iniciação de Transcrição , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Proteína Homeobox SIX3
10.
Mol Biol Rep ; 46(2): 2577-2593, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30758807

RESUMO

Wheat is an important cereal crop that fulfils the calorie demands of the global humanity. Rapidly expanding populations are exposed to a fast approaching acute shortage in the adequate supply of food and fibre from agricultural resources. One of the significant threats to food security lies in the constantly increasing global temperatures which inflict serious injuries to the plants in terms of various physiological, biochemical and molecular processes. Wheat being a cool season crop is majorly impacted by the heat stress which adversely affects crop productivity and yield. These challenges would be potentially defeated with the implementation of genetic engineering strategies coupled with the new genome editing approaches. Development of transgenic plants for various crops has proved very effective for the incorporation of improved varietal traits in context of heat stress. With a similar approach, we need to target for the generation of heat stress tolerant wheat varieties which are capable of survival in such adverse conditions and yet produce well. In this review, we enumerate the current status of research on the heat stress responsive genes/factors and their potential role in mitigating heat stress in plants particularly in wheat with an aim to help the researchers get a holistic view of this topic. Also, we discuss on the prospective signalling pathway that is triggered in plants in general under heat stress.


Assuntos
Termotolerância/genética , Triticum/genética , Triticum/metabolismo , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Genótipo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/fisiologia , Resposta ao Choque Térmico/genética , Temperatura Alta , Fenótipo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Poaceae/genética , Engenharia de Proteínas , Estresse Fisiológico/genética , Termotolerância/fisiologia , Triticum/fisiologia
11.
J Neuroeng Rehabil ; 16(1): 31, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30813963

RESUMO

BACKGROUND: Cerebellar damage can often result in disabilities affecting the peripheral regions of the body. These include poor and inaccurate coordination, tremors and irregular movements that often manifest as disorders associated with balance, gait and speech. The severity assessment of Cerebellar ataxia (CA) is determined by expert opinion and is likely to be subjective in nature. This paper investigates automated versions of three commonly used tests: Finger to Nose test (FNT), test for upper limb Dysdiadochokinesia Test (DDK) and Heel to Shin Test (HST), in evaluating disability due to CA. METHODS: Limb movements associated with these tests are measured using Inertial Measurement Units (IMU) to capture the disability. Kinematic parameters such as acceleration, velocity and angle are considered in both time and frequency domain in three orthogonal axes to obtain relevant disability related information. The collective dominance in the data distributions of the underlying features were observed though the Principal Component Analysis (PCA). The dominant features were combined to substantiate the correlation with the expert clinical assessments through Linear Discriminant Analysis. Here, the Pearson correlation is used to examine the relationship between the objective assessments and the expert clinical scores while the performance was also verified by means of cross validation. RESULTS: The experimental results show that acceleration is a major feature in DDK and HST, whereas rotation is the main feature responsible for classification in FNT. Combining the features enhanced the correlations in each domain. The subject data was classified based on the severity information based on expert clinical scores. CONCLUSION: For the predominantly translational movement in the upper limb FNT, the rotation captures disability and for the DDK test with predominantly rotational movements, the linear acceleration captures the disability but cannot be extended to the lower limb HST. The orthogonal direction manifestation of ataxia attributed to sensory measurements was determined for each test. TRIAL REGISTRATION: Human Research and Ethics Committee, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia (HREC Reference Number: 11/994H/16).


Assuntos
Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/fisiopatologia , Avaliação da Deficiência , Aceleração , Acelerometria , Adulto , Idoso , Idoso de 80 Anos ou mais , Automação , Fenômenos Biomecânicos , Análise Discriminante , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Movimento , Análise de Componente Principal , Reprodutibilidade dos Testes , Extremidade Superior/fisiopatologia
12.
Int J Mol Sci ; 20(10)2019 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-31130712

RESUMO

Salinity critically limits rice metabolism, growth, and productivity worldwide. Improvement of the salt resistance of locally grown high-yielding cultivars is a slow process. The objective of this study was to develop a new salt-tolerant rice germplasm using speed-breeding. Here, we precisely introgressed the hst1 gene, transferring salinity tolerance from "Kaijin" into high-yielding "Yukinko-mai" (WT) rice through single nucleotide polymorphism (SNP) marker-assisted selection. Using a biotron speed-breeding technique, we developed a BC3F3 population, named "YNU31-2-4", in six generations and 17 months. High-resolution genotyping by whole-genome sequencing revealed that the BC3F2 genome had 93.5% similarity to the WT and fixed only 2.7% of donor parent alleles. Functional annotation of BC3F2 variants along with field assessment data indicated that "YNU31-2-4" plants carrying the hst1 gene had similar agronomic traits to the WT under normal growth condition. "YNU31-2-4" seedlings subjected to salt stress (125 mM NaCl) had a significantly higher survival rate and increased shoot and root biomasses than the WT. At the tissue level, quantitative and electron probe microanalyzer studies indicated that "YNU31-2-4" seedlings avoided Na+ accumulation in shoots under salt stress. The "YNU31-2-4" plants showed an improved phenotype with significantly higher net CO2 assimilation and lower yield decline than WT under salt stress at the reproductive stage. "YNU31-2-4" is a potential candidate for a new rice cultivar that is highly tolerant to salt stress at the seedling and reproductive stages, and which might maintain yields under a changing global climate.


Assuntos
Oryza/genética , Tolerância ao Sal , Cruzamentos Genéticos , Genes de Plantas , Oryza/fisiologia , Melhoramento Vegetal , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
13.
New Phytol ; 217(1): 320-331, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28895153

RESUMO

The fungus Zymoseptoria tritici is the causal agent of Septoria Tritici Blotch (STB) disease of wheat leaves. Zymoseptoria tritici secretes many functionally uncharacterized effector proteins during infection. Here, we characterized a secreted ribonuclease (Zt6) with an unusual biphasic expression pattern. Transient expression systems were used to characterize Zt6, and mutants thereof, in both host and non-host plants. Cell-free protein expression systems monitored the impact of Zt6 protein on functional ribosomes, and in vitro assays of cells treated with recombinant Zt6 determined toxicity against bacteria, yeasts and filamentous fungi. We demonstrated that Zt6 is a functional ribonuclease and that phytotoxicity is dependent on both the presence of a 22-amino-acid N-terminal 'loop' region and its catalytic activity. Zt6 selectively cleaves both plant and animal rRNA species, and is toxic to wheat, tobacco, bacterial and yeast cells, but not to Z. tritici itself. Zt6 is the first Z. tritici effector demonstrated to have a likely dual functionality. The expression pattern of Zt6 and potent toxicity towards microorganisms suggest that, although it may contribute to the execution of wheat cell death, it is also likely to have an important secondary function in antimicrobial competition and niche protection.


Assuntos
Anti-Infecciosos/isolamento & purificação , Ascomicetos/enzimologia , Doenças das Plantas/microbiologia , Ribonucleases/isolamento & purificação , Triticum/microbiologia , Anti-Infecciosos/metabolismo , Ascomicetos/patogenicidade , Morte Celular/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Microbiota/efeitos dos fármacos , Micotoxinas/genética , Micotoxinas/isolamento & purificação , Micotoxinas/metabolismo , Folhas de Planta/microbiologia , Ribonucleases/genética , Ribonucleases/metabolismo
14.
Int J Mol Sci ; 19(7)2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30004453

RESUMO

Curcumin, a natural polyphenolic compound isolated from the plant Curcuma longa, is known to induce autophagy in various cancer cells, including lung cancer. In the present study, we also confirmed by LC3 immunofluorescence and immunoblotting analyses that curcumin triggers autophagy in the human lung adenocarcinoma A549 cell line. In parallel with autophagy induction, the gene expression of human GD3 synthase (hST8Sia I) responsible for ganglioside GD3 synthesis was markedly elevated in response to curcumin in the A549 cells. To investigate the transcriptional activation of hST8Sia I associated with the autophagy formation in curcumin-treated A549 cells, functional characterization of the 5'-flanking region of the hST8Sia I gene was carried out using the luciferase reporter assay system. Deletion analysis demonstrated that the -1146 to -646 region, which includes the putative c-Ets-1, CREB, AP-1, and NF-κB binding sites, functions as the curcumin-responsive promoter of hST8Sia I in A549 cells. The site-directed mutagenesis and chromatin immunoprecipitation assay demonstrated that the NF-κB binding site at -731 to -722 was indispensable for the curcumin-induced hST8Sia I gene expression in A549 cells. Moreover, the transcriptional activation of hST8Sia I by the curcumin A549 cells was strongly inhibited by compound C, an inhibitor of AMP-activated protein kinase (AMPK). These results suggest that curcumin controls hST8Sia I gene expression via AMPK signal pathway in A549 cells.


Assuntos
Adenocarcinoma/enzimologia , Autofagia/efeitos dos fármacos , Curcumina/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/enzimologia , Proteínas de Neoplasias/biossíntese , Sialiltransferases/biossíntese , Células A549 , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Indução Enzimática/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia
15.
Biochim Biophys Acta ; 1858(7 Pt A): 1507-32, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27058983

RESUMO

The crystal structure of the dimeric membrane domain of human Band 3(1), the red cell chloride/bicarbonate anion exchanger 1 (AE1, SLC4A1), provides a structural context for over four decades of studies into this historic and important membrane glycoprotein. In this review, we highlight the key structural features responsible for anion binding and translocation and have integrated the following topological markers within the Band 3 structure: blood group antigens, N-glycosylation site, protease cleavage sites, inhibitor and chemical labeling sites, and the results of scanning cysteine and N-glycosylation mutagenesis. Locations of mutations linked to human disease, including those responsible for Southeast Asian ovalocytosis, hereditary stomatocytosis, hereditary spherocytosis, and distal renal tubular acidosis, provide molecular insights into their effect on Band 3 folding. Finally, molecular dynamics simulations of phosphatidylcholine self-assembled around Band 3 provide a view of this membrane protein within a lipid bilayer.


Assuntos
Desequilíbrio Ácido-Base/sangue , Acidose Tubular Renal/sangue , Anemia Hemolítica Congênita/sangue , Proteína 1 de Troca de Ânion do Eritrócito/química , Eliptocitose Hereditária/sangue , Erros Inatos do Metabolismo/sangue , Esferocitose Hereditária/sangue , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Desequilíbrio Ácido-Base/genética , Desequilíbrio Ácido-Base/patologia , Acidose Tubular Renal/genética , Acidose Tubular Renal/patologia , Anemia Hemolítica Congênita/genética , Anemia Hemolítica Congênita/patologia , Proteína 1 de Troca de Ânion do Eritrócito/antagonistas & inibidores , Proteína 1 de Troca de Ânion do Eritrócito/genética , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Bicarbonatos/metabolismo , Eliptocitose Hereditária/genética , Eliptocitose Hereditária/patologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Eritrócitos Anormais/patologia , Expressão Gênica , Glicosilação , Humanos , Ligantes , Erros Inatos do Metabolismo/genética , Erros Inatos do Metabolismo/patologia , Mutação , Ligação Proteica , Esferocitose Hereditária/genética , Esferocitose Hereditária/patologia
16.
Int J Mol Sci ; 17(8)2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27490539

RESUMO

In this research, we firstly demonstrated that physcion, an anthraquinone derivative, specifically increased the expression of the human α2,8-sialyltransferase (hST8Sia VI) gene in SK-N-BE(2)-C human neuroblastoma cells. To establish the mechanism responsible for the up-regulation of hST8Sia VI gene expression in physcion-treated SK-N-BE(2)-C cells, the putative promoter region of the hST8Sia VI gene was functionally characterized. Promoter analysis with serially truncated fragments of the 5'-flanking region showed that the region between -320 and -240 is crucial for physcion-induced transcription of hST8Sia VI in SK-N-BE(2)-C cells. Putative binding sites for transcription factors Pax-5 and NF-Y are located at this region. The Pax-5 binding site at -262 to -256 was essential for the expression of the hST8Sia VI gene by physcion in SK-N-BE(2)-C cells. Moreover, the transcription of hST8Sia VI induced by physcion in SK-N-BE(2)-C cells was inhibited by extracellular signal-regulated protein kinase (ERK) inhibitor U0126 and p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580, but not c-Jun N-terminal kinase (JNK) inhibitor SP600125. These results suggest that physcion upregulates hST8Sia VI gene expression via ERK and p38 MAPK pathways in SK-N-BE(2)-C cells.


Assuntos
Neoplasias Encefálicas/genética , Emodina/análogos & derivados , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neuroblastoma/genética , Sialiltransferases/genética , Regulação para Cima/efeitos dos fármacos , Região 5'-Flanqueadora/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Sequência de Bases , Neoplasias Encefálicas/enzimologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Emodina/química , Emodina/isolamento & purificação , Emodina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Neuroblastoma/enzimologia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Deleção de Sequência , Sialiltransferases/metabolismo , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética , Regulação para Cima/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
FEMS Yeast Res ; 15(6)2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26122277

RESUMO

Candida glabrata is a fungal pathogen frequently found as a commensal in humans. To colonize and disseminate successfully in the mammalian host, C. glabrata must detect signals within the host and reprogram gene expression to respond appropriately to hostile environmental conditions. One of the layers of regulation of expression of many virulence-related genes (adhesin-encoding genes, genes involved in response to oxidative stress and xenobiotics) is achieved through epigenetic mechanisms. Local and regional silencing is mediated by the activity of two NAD(+)-dependent histone deacetylases, Hst1 and Sir2, respectively, repressing many virulence genes. Hst1 and Sir2 interact with different repressor complexes to achieve regional or local silencing. Sir2 can associate with Sir4, which is then recruited to the telomere by Rap1 and yKu. Deacetylation of the histone tails creates high affinity binding sites for new molecules of the Sir complex, thereby spreading the silent domain over >20 kb. Many of the adhesin-encoding EPA genes are subject to this regulation. Hst1 in turn associates with the Sum1-Rfm1 complex. Sum1 is a DNA-binding protein, which recognizes specific sites at individual promoters, recruiting Hst1 to specific genes involved in the response to oxidative stress and xenobiotics, which results in their repression.


Assuntos
Candida glabrata/genética , Candida glabrata/fisiologia , Adesão Celular , Cromatina/metabolismo , Epigênese Genética , Regulação Fúngica da Expressão Gênica , Estresse Fisiológico , Animais , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Histona Desacetilases/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Mapas de Interação de Proteínas
18.
Int J Mol Sci ; 17(1)2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26729095

RESUMO

Serum deprivation (SD) is well known to induce G0/G1 cell cycle arrest and apoptosis in various cells. In the present study, we firstly found that SD could induce G1 arrest and the differentiation of human osteoblastic MG-63 cells, as evidenced by the increase of osteoblastic differentiation markers, such as bone morphogenetic protein-2 (BMP-2), osteocalcin and runt-related transcription factor 2 (Runx2). In parallel, gene expression of human GM3 synthase (hST3Gal V) catalyzing ganglioside GM3 biosynthesis was upregulated by SD in MG-63 cells. The 5'-flanking region of the hST3Gal V gene was functionally characterized to elucidate transcriptional regulation of hST3Gal V in SD-induced MG-63 cells. Promoter analysis using 5'-deletion constructs of the hST3Gal V gene demonstrated that the -432 to -177 region functions as the SD-inducible promoter. Site-directed mutagenesis revealed that the Runx2 binding sites located side-by-side at positions -232 and -222 are essential for the SD-induced expression of hST3Gal V in MG-63 cells. In addition, the chromatin immunoprecipitation assay also showed that Runx2 specifically binds to the hST3Gal V promoter region containing Runx2 binding sites. These results suggest that SD triggers upregulation of hST3Gal V gene expression through Runx2 activation by BMP signaling in MG-63 cells.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core , Osteoblastos/metabolismo , Sialiltransferases/genética , Ativação Transcricional , Região 5'-Flanqueadora , Linhagem Celular , Humanos , Osteoblastos/fisiologia
19.
Pak J Med Sci ; 31(4): 941-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26430434

RESUMO

BACKGROUNDS & OBJECTIVE: End-stage renal disease (ESRD) frequently causes Protein Energy Wasting (PEW), which is an important morbidity and mortality factor. Although it is difficult to assess PEW with a reliable method, there are various methods such as Handgrip strength test (HST), serum albumin, cholesterol, etc. HST is a simple and reliable antropometric method which is used for nutritional status and body muscle strength. This study aims to assess the relationship between HST and biochemical markers in evolution of nutritional status of ESRD patients. METHODS: This cross-sectional study included 36 consecutive patients, who are on peritoneal dialysis and 36 healthy -control subjects. Jamar-hand dynamometer was used for handgrip strength test; a pinch gauge was used for key pinch. Other antropometric tests included skin fold thicknesses at biceps, triceps, umbilical, suprailiac and subscapular regions; circumferences at waist hip, neck and midarm. Biochemical tests were performed only in Peritoneal Dialysis (PD) group. SPSS for Windows ver. 15.0 was used for statistics. RESULTS: The mean age of patients was 49.3±14.4, and mean age of control group was 43.8±10.6 (p=0.075). In PD group dominant hand dynamometer test 1,2 and 3 results were 19.3±9.3 kg, 25.3±10.8 kg, 25.5± 10.6 kg and; 34.2±10.3 kg, 34.4±9.8 kg, 34.6±10.0 kg for control group (p< 0,001). Right key pinch results were 6.7±1.9 kg for patients; 13.5±4.5 kg for control group (p<0.001). Left key pinch results were 6.8±1.9 kg for patients; 13.2±4.4 kg for control group (p<0.001). There was not any significant relationship concerning handgrip or key pinch tests with biochemical parameters. CONCLUSION: Handgrip Strength Test and key pinch may be reliable, cheap and easily performed tests for the diagnosis of Protein Energy Wasting in patients on Peritoneal Dialysis.

20.
Vet Rec ; : e4599, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285679

RESUMO

BACKGROUND: Cardiac biomarker concentrations are elevated in dogs with pancreatitis, but it is unknown if this is also the case for cats. METHODS: The serum feline pancreatic lipase immunoreactivity (fPLI) of serum samples from 60 cats was quantified using the Spec fPL assay. Serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin I (HST) concentrations were also measured using commercial assays. RESULTS: Five of 20 cats with fPLI concentrations of 8.8 mg/L or more had above reference interval NT-proBNP concentrations. Serum NT-proBNP concentrations were not correlated with fPLI concentrations (p = 0.31) and were not different in each diagnostic category for fPLI results (p = 0.24). Serum HST concentrations were positively correlated with fPLI concentrations (r = 0.278, 95% confidence interval: 0.02‒0.50, p = 0.03). However, they were not significantly different in each diagnostic category for fPLI results (p = 0.16). LIMITATIONS: Unidentified co-variates could contribute to the association between fPLI and cardiac biomarker concentrations. CONCLUSIONS: Cats with elevated fPLI concentrations may have elevated cardiac biomarker concentrations.

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