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1.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205081

RESUMO

Although new genes can arrive from modes other than duplication, few examples are well characterized. Given high expression in some human brain subregions and a putative link to psychological disorders [e.g., schizophrenia (SCZ)], suggestive of brain functionality, here we characterize piggyBac transposable element-derived 1 (PGBD1). PGBD1 is nonmonotreme mammal-specific and under purifying selection, consistent with functionality. The gene body of human PGBD1 retains much of the original DNA transposon but has additionally captured SCAN and KRAB domains. Despite gene body retention, PGBD1 has lost transposition abilities, thus transposase functionality is absent. PGBD1 no longer recognizes piggyBac transposon-like inverted repeats, nonetheless PGBD1 has DNA binding activity. Genome scale analysis identifies enrichment of binding sites in and around genes involved in neuronal development, with association with both histone activating and repressing marks. We focus on one of the repressed genes, the long noncoding RNA NEAT1, also dysregulated in SCZ, the core structural RNA of paraspeckles. DNA binding assays confirm specific binding of PGBD1 both in the NEAT1 promoter and in the gene body. Depletion of PGBD1 in neuronal progenitor cells (NPCs) results in increased NEAT1/paraspeckles and differentiation. We conclude that PGBD1 has evolved core regulatory functionality for the maintenance of NPCs. As paraspeckles are a mammal-specific structure, the results presented here show a rare example of the evolution of a novel gene coupled to the evolution of a contemporaneous new structure.


Assuntos
Elementos de DNA Transponíveis , RNA Longo não Codificante , Animais , Núcleo Celular/genética , Histonas/metabolismo , Humanos , Mamíferos/genética , Mamíferos/metabolismo , Proteínas do Tecido Nervoso , Paraspeckles , RNA Longo não Codificante/metabolismo , Transposases/genética , Transposases/metabolismo
2.
Nature ; 516(7531): 405-9, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25317556

RESUMO

Naive embryonic stem cells hold great promise for research and therapeutics as they have broad and robust developmental potential. While such cells are readily derived from mouse blastocysts it has not been possible to isolate human equivalents easily, although human naive-like cells have been artificially generated (rather than extracted) by coercion of human primed embryonic stem cells by modifying culture conditions or through transgenic modification. Here we show that a sub-population within cultures of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) manifests key properties of naive state cells. These naive-like cells can be genetically tagged, and are associated with elevated transcription of HERVH, a primate-specific endogenous retrovirus. HERVH elements provide functional binding sites for a combination of naive pluripotency transcription factors, including LBP9, recently recognized as relevant to naivety in mice. LBP9-HERVH drives hESC-specific alternative and chimaeric transcripts, including pluripotency-modulating long non-coding RNAs. Disruption of LBP9, HERVH and HERVH-derived transcripts compromises self-renewal. These observations define HERVH expression as a hallmark of naive-like hESCs, and establish novel primate-specific transcriptional circuitry regulating pluripotency.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Retrovirus Endógenos/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Células Cultivadas , Elementos de DNA Transponíveis , Retrovirus Endógenos/genética , Perfilação da Expressão Gênica , Marcadores Genéticos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/virologia , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/metabolismo
3.
Biomedicines ; 12(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540259

RESUMO

Therapeutic recombinant proteins are powerful tools used for the treatment of many detrimental diseases such as diabetes, cancer, multiple sclerosis, rheumatoid arthritis, hepatitis, and many more. Their importance in disease therapy is growing over small molecule drugs because of their advantages like specificity and reduced side effects. However, the large-scale production of certain recombinant proteins is still challenging despite impressive advancements in biomanufacturing. The complement cascade is considered a rich source of drug targets and natural regulator proteins with great therapeutic potential. However, the versatility of such proteins has been hampered by low production rates. The recent discoveries highlighted here may bring definite improvement in the large-scale recombinant production of complement inhibitor proteins or other difficult-to-express proteins in mammalian cell lines.

4.
Neuroimmunomodulation ; 20(2): 79-86, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23235351

RESUMO

OBJECTIVES: Antimuscarinic acetylcholine receptor-3 (m3AChR) autoantibodies have been described in primary Sjögren's syndrome (pSS). The aim of this study was to compare various methods for their detection and to assess the contributions of anti-m3AChR and other immunological and psychosocial factors to the pathomechanism of secondary SS (sSS). METHODS: Sixty-five rheumatoid arthritis (RA) patients, 103 systemic lupus erythematosus (SLE) patients, 76 pSS patients and 50 controls were compared. Three immunodominant epitopes of m3AChR were synthesized and used in ELISA. Two extracellular epitopes were also prepared in fusion with glutathione-S-transferase and one in conjugation with bovine serum albumin. Mental health status was assessed with the 36-item Short-Form Health Survey and Functional Assessment of Chronic Illness Therapy fatigue scale. Correlations were evaluated between glandular function and anti-m3AChR positivities and specificities, features of SLE and RA, and mental health parameters. RESULTS: Fourteen RA and 27 SLE patients had sSS. The autoantibody levels to all epitopes of m3AChR were significantly higher in pSS and SLE patients than in the controls. The fusion protein forms discriminated RA from pSS and SLE; furthermore, the YNIP fusion protein also distinguished pSS from SLE. The prevalence and the mean levels of all autoantibodies did not differ statistically between sicca and non-sicca SLE or RA patients. Glandular dysfunction correlated with higher age in SLE and RA and an impaired health-related quality of life in SLE. CONCLUSIONS: The second and third extracellular loops of m3AChR are antigenic in pSS. Immunoassays with antigens as fusion peptides demonstrate the best performance. Sicca SLE patients have worse mental health status. Anti-m3AChR antibodies represent a peculiar example of neuroimmune interactions.


Assuntos
Autoanticorpos/imunologia , Glândulas Exócrinas/fisiopatologia , Receptores Muscarínicos/imunologia , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/fisiopatologia , Síndrome de Sjogren/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Autoantígenos/sangue , Autoantígenos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimunomodulação , Testes Neuropsicológicos , Adulto Jovem
5.
World J Microbiol Biotechnol ; 28(4): 1843-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805970

RESUMO

Kaolin is an important industrial raw material and a basis of a range of different products. Microbial spoilage is a detrimental process observed especially in kaolin slurries, leading to low quality products and economic loss. Although the alteration of kaolin slurries in ceramic industry was observed, the process and the microbial background have not been analyzed in details. This study provides the first data using a cultivation independent molecular biological approach (PCR-DGGE) regarding the bacterial composition of an altered kaolin slurry. The results show that potential exopolymer (EPS) producer bacteria (e.g. Acinetobacter, Pseudomonas) appear in the altered kaolin slurry, which may have an important role in the modification of kaolin slurries.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Eletroforese em Gel de Gradiente Desnaturante/métodos , Microbiologia Ambiental , Caulim , Reação em Cadeia da Polimerase/métodos , Bactérias/metabolismo , Microbiologia Industrial , Polímeros/metabolismo
6.
Z Naturforsch C J Biosci ; 65(11-12): 693-700, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21319712

RESUMO

The newly isolated strain E1, identified as a Dietzia sp., proved to have an excellent ability to degrade n-C12 to n-C38 alkane components of crude oil. The preferred substrate was the very long-chain alkane n-eicosane at an optimal temperature of 37 degrees C and an optimal pH of 8 under aerobic conditions. The growth and substrate uptake kinetics were monitored during the n-alkane fermentation process, and Dietzia sp. E1 cells were found to possess three distinct levels of cell-surface hydrophobicity. Gas chromatographic/mass spectrometric analysis revealed that intracellular substrate mineralization occurred through the conversion of n-alkane to the corresponding n-alkanal. The monoterminal oxidation pathway was presumably initiated by AlkB and CYP153 terminal alkane hydroxylases, both of their partial coding sequences were successfully detected in the genome of strain E1, a novel member of the Dietzia genus.


Assuntos
Actinobacteria/metabolismo , Alcanos/metabolismo , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Biodegradação Ambiental , Citocromo P-450 CYP4A/genética , Cromatografia Gasosa-Espectrometria de Massas
7.
Z Naturforsch C J Biosci ; 65(1-2): 134-40, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20355333

RESUMO

Strain T1E, isolated and identified as Brevibacillus thermoruber, and evolutionally distant from the known keratinolytic isolates, proved to have feather-degrading ability. During the 7-day fermentation period, T1E consumed 10 g/l native goose feathers as the sole source of carbon and energy at 50 degrees C under aerobic conditions. The isolate secreted a thermostable, keratinolytic protease, which exhibited activity optimally at pH 6.5, whilst it was inhibited at alkaline pH. The keratin cleavage and catabolism resulted in the accumulation of free aspartic acid and soluble peptides with maximum values of 31.6 and 720 mg/l, respectively. The majority of the fermentation end-products were found to be small oligopeptides with an average molecular mass of 2275 Da.


Assuntos
Bacillus/enzimologia , Plumas/metabolismo , Peptídeo Hidrolases/metabolismo , Animais , Ácido Aspártico/análise , Bacillus/crescimento & desenvolvimento , DNA Ribossômico/genética , Plumas/química , Fermentação , Gansos , Cinética , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Streptomyces/enzimologia
8.
Elife ; 72018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29377792

RESUMO

Proteins are necessary for cellular growth. Concurrently, however, protein production has high energetic demands associated with transcription and translation. Here, we propose that activity of molecular chaperones shape protein burden, that is the fitness costs associated with expression of unneeded proteins. To test this hypothesis, we performed a genome-wide genetic interaction screen in baker's yeast. Impairment of transcription, translation, and protein folding rendered cells hypersensitive to protein burden. Specifically, deletion of specific regulators of the Hsp70-associated chaperone network increased protein burden. In agreement with expectation, temperature stress, increased mistranslation and a chemical misfolding agent all substantially enhanced protein burden. Finally, unneeded protein perturbed interactions between key components of the Hsp70-Hsp90 network involved in folding of native proteins. We conclude that specific chaperones contribute to protein burden. Our work indicates that by minimizing the damaging impact of gratuitous protein overproduction, chaperones enable tolerance to massive changes in genomic expression.


Assuntos
Metabolismo Energético , Proteínas de Choque Térmico HSP72/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo
9.
FEMS Microbiol Lett ; 275(1): 71-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17662058

RESUMO

The GltS Na+/glutamate permease of Escherichia coli is the most extensively studied member of the ESS family of bacterial glutamate:Na+ symporters. This paper presents the membrane topology analysis of the GltS with translational alkaline phosphatase and beta-galactosidase gene fusions generated by TnphoA, nested deletions and targeted fusions. The topology model suggested by the translational fusion technique is compared with the MemGen model and discussed in detail.


Assuntos
Sistemas de Transporte de Aminoácidos Acídicos/análise , Sistemas de Transporte de Aminoácidos Acídicos/metabolismo , Membrana Celular/enzimologia , Proteínas de Escherichia coli/análise , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Biossíntese de Proteínas , Simportadores/análise , Simportadores/metabolismo , Fosfatase Alcalina/análise , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Sequência de Aminoácidos , Sistemas de Transporte de Aminoácidos Acídicos/genética , Fusão Gênica Artificial , Proteínas de Escherichia coli/genética , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Simportadores/genética , beta-Galactosidase/análise , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
10.
Acta Pharm Hung ; 73(4): 221-36, 2003.
Artigo em Húngaro | MEDLINE | ID: mdl-15279035

RESUMO

The "inorganic medical chemistry" is a rapidly developing field with enormous potential for applications, which offers new possibilities to the pharmaceutical industry. For example, the titanocene dichloride is already in clinical use, and antimetastatic activity of a range of Ru(III) complexes is also well established. There are ways to minimize the toxicity of Gd(III) complexes and therefore they can be safely injected as MRI contrast agents. The so called "ligand design" allows paramagnetic ions to be targeted to specific organs. Such designed ligands also enable the targeting of radiodiagnostic (99mTc) and radiotherapeutic (186Re) isotopes. There is a significant progress in understanding the coordination chemistry and biochemistry of metal ion(s) containing complexes such as Au antiarthritic and Bi antiulcer drugs. Further, currently developing areas include Mn (SOD mimics), V (insulin mimics), Ru (NO scavengers), Ln-based photosensitizers, metal-targeted organic agents and the Fe overload. The expanding knowledge of the role of metals in biochemistry is expected to provide scope for the design of new drugs in many other areas too, for example neuropharmaceutical and antiaffective agents. Progress in coordination chemistry is strongly dependent on understanding not only the thermodynamics of reactions, but also the kinetics of metal complexes under biologically relevant conditions.


Assuntos
Química Farmacêutica/métodos , Metais , Química Farmacêutica/tendências , Ligantes , Metais/toxicidade
11.
FEMS Microbiol Lett ; 316(2): 100-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21204932

RESUMO

The genetic background of long-chain n-alkane degradation was investigated in detail in strain E1, a member of the genetically unexplored Dietzia genus. A suicide vector carrying a 518-bp alkB fragment was site-specifically integrated into the E1 chromosome, and the full alkB, as well as its chromosomal environment was sequenced after plasmid rescue experiments. Four out of the nine putative genes were strongly induced by long-chain n-alkanes in wild-type E1. ORF4 encoded a natural fusion protein consisting of an integral membrane alkane hydroxylase and a rubredoxin domain. The significance of the alkB-rub gene in n-alkane degradation was investigated in phenotypic tests, and the disruption mutant strain exhibited severely impaired growth on n-C(20) alkane carbon source. The mutation was successfully complemented with the expression of intact AlkB-Rub protein, the full-length form of which was detected by simultaneous immunoblotting. The presented data furnish the first experimental evidence of the in vivo existence of an AlkB-Rub natural fusion protein, which plays a major role in long-chain n-alkane degradation.


Assuntos
Actinomycetales/metabolismo , Alcanos/metabolismo , Actinomycetales/química , Actinomycetales/enzimologia , Actinomycetales/genética , Alcanos/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Citocromo P-450 CYP4A/química , Citocromo P-450 CYP4A/genética , Citocromo P-450 CYP4A/metabolismo , Dados de Sequência Molecular , Alinhamento de Sequência
12.
J Bacteriol ; 184(17): 4930-2, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12169620

RESUMO

The metD D-methionine transporter locus of Escherichia coli was identified as the abc-yaeE-yaeC cluster (now renamed metNIQ genes). The abc open reading frame is preceded by tandem MET boxes bracketed by the -10 and -35 boxes of a promoter. The expression driven by this promoter is controlled by the MetJ repressor and the level of methionine.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Sistemas de Transporte de Aminoácidos/genética , Escherichia coli/genética , Metionina/análogos & derivados , Família Multigênica , Mapeamento Cromossômico , Escherichia coli/metabolismo , Metionina/metabolismo , Transcrição Gênica
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