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1.
Nat Commun ; 10(1): 3042, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316054

RESUMO

Stress resistance and longevity are positively correlated but emerging evidence indicates that they are physiologically distinct. Identifying factors with distinctive roles in these processes is challenging because pro-longevity genes often enhance stress resistance. We demonstrate that TCER-1, the Caenorhabditis elegans homolog of human transcription elongation and splicing factor, TCERG1, has opposite effects on lifespan and stress resistance. We previously showed that tcer-1 promotes longevity in germline-less C. elegans and reproductive fitness in wild-type animals. Surprisingly, tcer-1 mutants exhibit exceptional resistance against multiple stressors, including infection by human opportunistic pathogens, whereas, TCER-1 overexpression confers immuno-susceptibility. TCER-1 inhibits immunity only during fertile stages of life. Elevating its levels ameliorates the fertility loss caused by infection, suggesting that TCER-1 represses immunity to augment fecundity. TCER-1 acts through repression of PMK-1 as well as PMK-1-independent factors critical for innate immunity. Our data establish key roles for TCER-1 in coordinating immunity, longevity and fertility, and reveal mechanisms that distinguish length of life from functional aspects of aging.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica/fisiologia , Imunidade Inata/genética , Longevidade/genética , Fatores de Alongamento de Peptídeos/metabolismo , Estresse Fisiológico/imunologia , Envelhecimento/genética , Envelhecimento/imunologia , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/imunologia , Suscetibilidade a Doenças/imunologia , Fertilidade/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Modelos Animais , Mutação , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/imunologia , Estresse Fisiológico/genética
2.
PLoS Genet ; 15(6): e1008179, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31237868

RESUMO

Translation elongation factor P (EF-P) alleviates ribosome pausing at a subset of motifs encoding consecutive proline residues, and is required for growth in many organisms. Here we show that Bacillus subtilis EF-P also alleviates ribosome pausing at sequences encoding tandem prolines and ribosomes paused within several essential genes without a corresponding growth defect in an efp mutant. The B. subtilis efp mutant is instead impaired for flagellar biosynthesis which results in the abrogation of a form of motility called swarming. We isolate swarming suppressors of efp and identify mutations in 8 genes that suppressed the efp mutant swarming defect, many of which encode conserved ribosomal proteins or ribosome-associated factors. One mutation abolished a translational pause site within the flagellar C-ring component FliY to increase flagellar number and restore swarming motility in the absence of EF-P. Our data support a model wherein EF-P-alleviation of ribosome pausing may be particularly important for macromolecular assemblies like the flagellum that require precise protein stoichiometries.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Membrana/genética , Fatores de Alongamento de Peptídeos/genética , Biossíntese de Proteínas , Supressão Genética , Bacillus subtilis/genética , Movimento Celular/genética , Flagelos/genética , Mutação , Proteínas Ribossômicas/genética , Ribossomos/genética
3.
Mol Med Rep ; 19(6): 5263-5274, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059041

RESUMO

Genetic biomarkers for the diagnosis of ankylosing spondylitis (AS) remain unreported except for human leukocyte antigen B27 (HLA­B27). Therefore, the aim of the present study was to screen the differentially expressed genes (DEGs), and those that also possess differential single nucleotide polymorphism (SNP) loci in the whole blood of AS patients compared with healthy controls by integrating two mRNA expression profiles (GSE73754 and GSE25101) and SNP microarray data (GSE39428) collected from the Gene Expression Omnibus (GEO). Using the t­test, 1,056 and 1,073 DEGs were identified in the GSE73754 and GSE25101 datasets, respectively. Among them, 234 DEGs were found to be shared in both datasets, which were subsequently overlapped with 122 differential SNPs of genes in the GSE39428 dataset, resulting in identification of two common genes [eukaryotic translation elongation factor 1 epsilon 1 (EEF1E1) and serpin family A member 1 (SERPINA1)]. Their expression levels were significantly upregulated and the average expression log R ratios of SNP sites in these genes were significantly higher in AS patients than those in controls. Function enrichment analysis revealed that EEF1E1 was involved in AS by influencing the aminoacyl­tRNA biosynthesis, while SERPINA1 may be associated with AS by participating in platelet degranulation. However, only the genotype and allele frequencies of SNPs (rs7763907 and rs7751386) in EEF1E1 between AS and controls were significantly different between AS and the controls, but not SERPINA1. These findings suggest that EEF1E1 may be an underlying genetic biomarker for the diagnosis of AS.


Assuntos
Biomarcadores/metabolismo , Fatores de Alongamento de Peptídeos/genética , Espondilite Anquilosante/diagnóstico , Proteínas Supressoras de Tumor/genética , Alelos , Estudos de Casos e Controles , Bases de Dados Genéticas , Frequência do Gene , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Mapas de Interação de Proteínas/genética , RNA de Transferência/metabolismo , Espondilite Anquilosante/genética , Transcriptoma , alfa 1-Antitripsina/genética
4.
Nat Commun ; 10(1): 1207, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30872584

RESUMO

In bacteria, transcription-coupled repair of DNA lesions initiates after the Mfd protein removes RNA polymerases (RNAPs) stalled at the lesions. The bacterial RNA helicase, Rho, is a transcription termination protein that dislodges the elongation complexes. Here, we show that Rho dislodges the stalled RNAPs at DNA lesions. Strains defective in both Rho and Mfd are susceptible to DNA-damaging agents and are inefficient in repairing or propagating UV-damaged DNA. In vitro transcription assays show that Rho dissociates the stalled elongation complexes at the DNA lesions. We conclude that Rho-dependent termination recycles stalled RNAPs, which might facilitate DNA repair and other DNA-dependent processes essential for bacterial cell survival. We surmise that Rho might compete with, or augment, the Mfd function.


Assuntos
Reparo do DNA/fisiologia , RNA Polimerases Dirigidas por DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiologia , Terminação da Transcrição Genética/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , DNA Bacteriano/metabolismo , Proteínas de Escherichia coli/genética , Mitomicina/farmacologia , Mutação , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , RNA Bacteriano/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Raios Ultravioleta/efeitos adversos
5.
Cell Physiol Biochem ; 52(3): 435-438, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873819

RESUMO

BACKGROUND/AIMS: Tachycardiomyopathy (TCM) is a largely reversible form of non-ischemic heart failure. The underlying mechanism are, however, still today poorly understood. Recent data indicate distinct changes in mitochondrial distribution in these patients, compared to other non-ischemic cardiomyopathies.This study investigated underlying mechanisms in mitochondrial dynamics in endomyocardial biopsy samples (EMB) from patients with TCM and compared them to patients with dilated cardiomyopathy (DCM), which show similar clinical features. METHODS: Focused mRNA analyses were performed on routinely obtained paraffinfixed EMB specimen from patients fulfilling TCM diagnosis criteria, as well as patients with DCM to elucidate regulatory changes in mitochondrial fusion, fission and mitophagy. RESULTS: In patients with TCM we were able to identify mRNA of Mitofusin 1 and 2, two effector proteins regulating mitochondrial fusion, to be strongly upregulated compared to patients with DCM. Conclusively, we did not find differences in the mRNA expression of mitochondrial fission regulators including DRP1, Fis1, MFF, MiD49, and MiD51. Furthermore, we did not find significant changes in PINK1 expression, an important mediator for mitochondrial autophagy. CONCLUSION: The mRNA upregulation of Mitofusin 1 and 2 provides first insight into the complex changes of mitochondrial dynamics in cardiomyocytes of patients with reversible heart failure due to TCM.


Assuntos
Cardiomiopatia Dilatada/genética , GTP Fosfo-Hidrolases/genética , Mitocôndrias/genética , Dinâmica Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas Mitocondriais/genética , RNA Mensageiro/genética , Biópsia , Cardiomiopatia Dilatada/classificação , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/fisiopatologia , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Frequência Cardíaca/fisiologia , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Degradação Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Mensageiro/metabolismo
6.
Curr Genet ; 65(3): 729-733, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30739200

RESUMO

The bacterial hexameric helicase known as Rho is an archetypal sequence-specific transcription terminator that typically halts the synthesis of a defined set of transcripts, particularly those bearing cytosine-rich 3'-untranslated regions. However, under conditions of translational stress, Rho can also terminate transcription at cytosine-poor sites when assisted by the transcription factor NusG. Recent structural, biochemical, and computational studies of the Rho·NusG interaction in Escherichia coli have helped establish how NusG reprograms Rho activity. NusG is found to be an allosteric activator of Rho that directly binds to the ATPase motor domain of the helicase and facilitates closure of the Rho ring around non-ideal (purine-rich) target RNAs. The manner in which NusG acts on Rho helps to explain how the transcription terminator is excluded from acting on RNA polymerase by exogenous factors, such as the antitermination protein NusE, the NusG paralog RfaH, and RNA polymerase-coupled ribosomes. Collectively, an understanding of the link between NusG and Rho provides new insights into how transcriptional and translational fidelity are maintained during gene expression in bacteria.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Fatores de Alongamento de Peptídeos/metabolismo , Fator Rho/metabolismo , Fatores de Transcrição/metabolismo , Terminação da Transcrição Genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Fatores de Alongamento de Peptídeos/genética , Fator Rho/genética , Fatores de Transcrição/genética
7.
PLoS One ; 14(1): e0211459, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30703167

RESUMO

Mitochondrial fission is facilitated by dynamin-related protein Drp1 and a variety of its receptors. However, the molecular mechanism of how Drp1 is recruited to the mitochondrial surface by receptors MiD49 and MiD51 remains elusive. Here, we showed that the interaction between Drp1 and MiD51 is regulated by GTP binding and depends on the polymerization of Drp1. We identified two regions on MiD51 that directly bind to Drp1, and found that dimerization of MiD51, relevant to residue C452, is required for mitochondrial dynamics regulation. Our Results have suggested a multi-faceted regulatory mechanism for the interaction between Drp1 and MiD51 that illustrates the potentially complicated and tight regulation of mitochondrial fission.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Dinâmica Mitocondrial , Proteínas Mitocondriais/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Sequência de Aminoácidos , Cristalografia por Raios X , GTP Fosfo-Hidrolases/química , GTP Fosfo-Hidrolases/genética , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/genética , Proteínas Mitocondriais/química , Proteínas Mitocondriais/genética , Modelos Moleculares , Fatores de Alongamento de Peptídeos/química , Fatores de Alongamento de Peptídeos/genética , Conformação Proteica , Homologia de Sequência
8.
Nat Commun ; 10(1): 702, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30742024

RESUMO

RfaH, member of the NusG/Spt5 family, activates virulence genes in Gram-negative pathogens. RfaH exists in two states, with its C-terminal domain (CTD) folded either as α-helical hairpin or ß-barrel. In free RfaH, the α-helical CTD interacts with, and masks the RNA polymerase binding site on, the N-terminal domain, autoinhibiting RfaH and restricting its recruitment to opsDNA sequences. Upon activation, the domains separate and the CTD refolds into the ß-barrel, which recruits a ribosome, activating translation. Using NMR spectroscopy, we show that only a complete ops-paused transcription elongation complex activates RfaH, probably via a transient encounter complex, allowing the refolded CTD to bind ribosomal protein S10. We also demonstrate that upon release from the elongation complex, the CTD transforms back into the autoinhibitory α-state, resetting the cycle. Transformation-coupled autoinhibition allows RfaH to achieve high specificity and potent activation of gene expression.


Assuntos
Proteínas de Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Dobramento de Proteína , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Simulação de Dinâmica Molecular , Fatores de Alongamento de Peptídeos/genética , Ligação Proteica , Biossíntese de Proteínas , Domínios e Motivos de Interação entre Proteínas , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA/genética , Proteínas Ribossômicas , Ribossomos , Transativadores/genética , Fatores de Transcrição/metabolismo , Transcrição Genética , Virulência/genética
9.
Clin Dysmorphol ; 27(2): 31-35, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29381487

RESUMO

Mandibulofacial dysostosis type Guion-Almeida (MFDGA) is a rare disease entity that results in congenital craniofacial anomalies that are caused by abnormal development of the first and second pharyngeal arches. MFDGA is characterized by malar and mandibular hypoplasia, microcephaly, developmental delay, dysplastic ears, and a distinctive facial appearance. Extracraniofacial malformations include esophageal atresia, congenital heart disease, and radial ray abnormalities. Heterozygous mutations in the elongation factor Tu GTP-binding domain containing 2 (EFTUD2) gene have been shown to result in MFDGA. To date, there have been a total of 108 individuals reported in the literature, of whom 95 patients have a confirmed EFTUD2 mutation. The majority of individuals reported in the literature have been of White ethnic origin. Here, we report two individuals of Asian ancestry with MFDGA, each harboring a novel, pathogenic splice site variant in EFTUD2.


Assuntos
Deficiências do Desenvolvimento/genética , Disostose Mandibulofacial/genética , Fatores de Alongamento de Peptídeos/genética , Ribonucleoproteína Nuclear Pequena U5/genética , Pré-Escolar , Deficiências do Desenvolvimento/fisiopatologia , Feminino , Heterozigoto , Humanos , Lactente , Masculino , Disostose Mandibulofacial/fisiopatologia , Mutação , Isoformas de Proteínas/genética
10.
Eur J Med Genet ; 61(6): 315-321, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29307790

RESUMO

Kabuki syndrome is mainly caused by dominant de-novo pathogenic variants in the KMT2D and KDM6A genes. The clinical features of this syndrome are highly variable, making the diagnosis of Kabuki-like phenotypes difficult, even for experienced clinical geneticists. Herein we present molecular genetic findings of causal genetic variation using array comparative genome hybridization and a Mendeliome analysis, utilizing targeted exome analysis focusing on regions harboring rare disease-causing variants in Kabuki-like patients which remained KMT2D/KDM6A-negative. The aCGH analysis revealed a pathogenic CNV in the 14q11.2 region, while targeted exome sequencing revealed pathogenic variants in genes associated with intellectual disability (HUWE1, GRIN1), including a gene coding for mandibulofacial dysostosis with microcephaly (EFTUD2). Lower values of the MLL2-Kabuki phenotypic score are indicative of Kabuki-like phenotype (rather than true Kabuki syndrome), where aCGH and Mendeliome analyses have high diagnostic yield. Based on our findings we conclude that for new patients with Kabuki-like phenotypes it is possible to choose a specific molecular testing approach that has the highest detection rate for a given MLL2-Kabuki score, thus fostering more precise patient diagnosis and improved management in these genetically- and phenotypically heterogeneous clinical entities.


Assuntos
Anormalidades Múltiplas/genética , Face/anormalidades , Heterogeneidade Genética , Genótipo , Doenças Hematológicas/genética , Fenótipo , Doenças Vestibulares/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/fisiopatologia , Criança , Pré-Escolar , Cromossomos Humanos Par 14 , Hibridização Genômica Comparativa , Proteínas de Ligação a DNA/genética , Exoma , Face/fisiopatologia , Feminino , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/fisiopatologia , Sequenciamento de Nucleotídeos em Larga Escala , Histona Desmetilases/genética , Humanos , Deficiência Intelectual/genética , Masculino , Disostose Mandibulofacial/genética , Microcefalia/genética , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fatores de Alongamento de Peptídeos/genética , Receptores de N-Metil-D-Aspartato/genética , Ribonucleoproteína Nuclear Pequena U5/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/fisiopatologia
11.
J Phys Chem B ; 122(5): 1600-1607, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29323497

RESUMO

Proteins such as the transcription factor RfaH can change biological function by switching between distinct three-dimensional folds. RfaH regulates transcription if the C-terminal domain folds into a double helix bundle and promotes translation when this domain assumes a ß-barrel form. This fold-switch has been also observed for the isolated C-terminal domain, dubbed by us as RfaH-C-terminal domain (RfaH-CTD), and is studied here with a variant of the replica-exchange-with-tunneling approach recently introduced by us. We use the enhanced sampling properties of this technique to map the free-energy landscape of RfaH-CTD and to propose a mechanism for the conversion process.


Assuntos
Proteínas de Escherichia coli/química , Fatores de Alongamento de Peptídeos/química , Dobramento de Proteína , Transativadores/química , Proteínas de Escherichia coli/genética , Simulação de Dinâmica Molecular , Fatores de Alongamento de Peptídeos/genética , Domínios Proteicos , Estrutura Terciária de Proteína , Transativadores/genética
12.
Enzyme Microb Technol ; 108: 21-25, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29108623

RESUMO

The utility of engineering flocculation is wildly recognized in applied and environmental microbiology. We previously reported self-produced flocculation of Escherichia coli cells by overexpressing the native bcsB gene that encodes a component of the cellulose synthesis pathway. Further experiments clarified that the spontaneous E. coli flocs were proteinous, and elongation factor Ts (Tsf) was the main component. In this study, we demonstrated successful expression of a fusion protein consisting of Tsf and green fluorescence protein (GFP) on E. coli flocs. Interestingly, the percentage of Tsf-GFP in total floc protein reached approximately 15% (w/w). The proposed design of a fusion protein with Tsf enables displaying a recombinant target protein on the floc structure.


Assuntos
Escherichia coli K12/metabolismo , Proteínas de Escherichia coli/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Técnicas Bacteriológicas , Bioengenharia , Escherichia coli K12/citologia , Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Floculação , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Fatores de Alongamento de Peptídeos/genética , Proteínas Recombinantes de Fusão/genética
13.
EMBO J ; 37(3): 413-426, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29237698

RESUMO

To maintain genome integrity, organisms employ DNA damage response, the underlying principles of which are conserved from bacteria to humans. The bacterial small RNA OxyS of Escherichia coli is induced upon oxidative stress and has been implicated in protecting cells from DNA damage; however, the mechanism by which OxyS confers genome stability remained unknown. Here, we revealed an OxyS-induced molecular checkpoint relay, leading to temporary cell cycle arrest to allow damage repair. By repressing the expression of the essential transcription termination factor nusG, OxyS enables read-through transcription into a cryptic prophage encoding kilR The KilR protein interferes with the function of the major cell division protein FtsZ, thus imposing growth arrest. This transient growth inhibition facilitates DNA damage repair, enabling cellular recovery, thereby increasing viability following stress. The OxyS-mediated growth arrest represents a novel tier of defense, introducing a new regulatory concept into bacterial stress response.


Assuntos
Pontos de Checagem do Ciclo Celular/genética , Dano ao DNA/genética , Reparo do DNA/genética , Proteínas de Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Proteínas Repressoras/genética , Proteínas de Bactérias/genética , Divisão Celular/genética , Proteínas do Citoesqueleto/genética , Proteínas de Escherichia coli/antagonistas & inibidores , Instabilidade Genômica/genética , Estresse Oxidativo/fisiologia , Fatores de Alongamento de Peptídeos/antagonistas & inibidores , Fatores de Alongamento de Peptídeos/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Genética/genética
14.
Transcription ; 9(2): 117-122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28886274

RESUMO

Characterisation of the Arabidopsis RNA polymerase II (RNAPII) elongation complex revealed an assembly of a conserved set of transcript elongation factors associated with chromatin remodellers, histone modifiers as well as with various pre-mRNA splicing and polyadenylation factors. Therefore, transcribing RNAPII streamlines the processes of mRNA synthesis and processing in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , RNA de Plantas/genética , Elongação da Transcrição Genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Fatores de Alongamento de Peptídeos/genética , Poliadenilação , RNA Polimerase II/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , Processamento de RNA , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo
15.
J Clin Lab Anal ; 32(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28332727

RESUMO

BACKGROUND: We aimed to investigate the distribution of selected BCL11A and HMIP polymorphisms (SNP's), and to assess the correlation with HPFH in a cohort of sickle cell patients. METHODS: A preliminary cross-sectional study was conducted in 102 patients. Group 1 was composed of patients with HPFH and Group 2 consisted of patients without HbF. We assessed 8 SNPs previously associated with HPFH in cohorts genetically close to the Congolese population. Observed frequencies were compared to expected frequencies. RESULTS: In the group 1, at rs7606173, the observed frequency for the genotype GG was significantly higher and the genotype GC was significantly lower than their respective expected frequencies. At rs9399137, the observed frequency of the genotype TT was significantly lower than expected. Conversely, the observed frequency of the genotype TC was significantly higher than expected. The observed frequency of the genotype TT at rs11886868 was significantly lower than the expected whereas the frequency of the genotype TC was significantly higher than observed. The lowest HbF level was recorded in patients with genotype CC at rs11886868. CONCLUSION: In this preliminary study, the results demonstrate that alleles of some of the 8 studied SNPs are not randomly distributed among patients with or without HPFH in this cohort.


Assuntos
Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Proteínas de Transporte/genética , DNA Intergênico/genética , Proteínas de Ligação ao GTP/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas Nucleares/genética , Fatores de Alongamento de Peptídeos/genética , Proteínas Proto-Oncogênicas c-myb/genética , Adolescente , Adulto , Criança , Estudos Transversais , República Democrática do Congo/epidemiologia , Hemoglobina Fetal , Frequência do Gene , Genótipo , Humanos , Adulto Jovem
16.
Plant Dis ; 102(8): 1527-1533, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30673419

RESUMO

Brown rot is a severe disease affecting stone and pome fruit. This disease was recently confirmed to be caused by the following six closely related species: Monilinia fructicola, M. laxa, M. fructigena, Monilia polystroma, M. mumecola, and M. yunnanensis. Because of differences in geographic distributions, some of these species are important quarantine pathogens in certain countries. In this study, we developed TaqMan real-time polymerase chain reaction (PCR) assays to detect and identify the six species. Primer pairs and probes were designed for Monilinia fructicola, M. fructigena, M. laxa, and Monilia polystroma based on sequence differences in the laccase-2 genes. Additionally, based on sequence differences in the elongation factor genes, primer pairs and probes were designed for Monilia mumecola and M. yunnanensis. The real-time PCR assays were able to specifically identify the target pathogens, with detection limits of 10 to 100 fg of DNA, which is equivalent to one to seven conidia. The assays were also able to detect the target pathogens in a mixed DNA sample comprising all six Monilinia spp. and related species. The real-time PCR assays accurately detected target fungi from infected apple fruit. Furthermore, the identification results were consistent with those of traditional morphological methods.


Assuntos
Ascomicetos/fisiologia , Frutas/microbiologia , Malus/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/classificação , Ascomicetos/genética , Sequência de Bases , DNA Fúngico/genética , Proteínas Fúngicas/genética , Lacase/genética , Micologia/métodos , Fatores de Alongamento de Peptídeos/genética , Reação em Cadeia da Polimerase/métodos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Esporos Fúngicos/genética
17.
Nat Commun ; 8(1): 2027, 2017 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-29229908

RESUMO

Nus factors are broadly conserved across bacterial species, and are often essential for viability. A complex of five Nus factors (NusB, NusE, NusA, NusG and SuhB) is considered to be a dedicated regulator of ribosomal RNA folding, and has been shown to prevent Rho-dependent transcription termination. Here, we identify an additional cellular function for the Nus factor complex in Escherichia coli: repression of the Nus factor-encoding gene, suhB. This repression occurs primarily by translation inhibition, followed by Rho-dependent transcription termination. Thus, the Nus factor complex can prevent or promote Rho activity depending on the gene context. Conservation of putative NusB/E binding sites upstream of Nus factor genes suggests that Nus factor autoregulation occurs in many bacterial species. Additionally, many putative NusB/E binding sites are also found upstream of other genes in diverse species, and we demonstrate Nus factor regulation of one such gene in Citrobacter koseri. We conclude that Nus factors have an evolutionarily widespread regulatory function beyond ribosomal RNA, and that they are often autoregulatory.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Dobramento de RNA , RNA Ribossômico/química , Sequência de Bases , Sítios de Ligação/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Ligação Proteica , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Homologia de Sequência do Ácido Nucleico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
18.
Mol Cell ; 68(3): 515-527.e6, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100052

RESUMO

Ribosomes synthesizing proteins containing consecutive proline residues become stalled and require rescue via the action of uniquely modified translation elongation factors, EF-P in bacteria, or archaeal/eukaryotic a/eIF5A. To date, no structures exist of EF-P or eIF5A in complex with translating ribosomes stalled at polyproline stretches, and thus structural insight into how EF-P/eIF5A rescue these arrested ribosomes has been lacking. Here we present cryo-EM structures of ribosomes stalled on proline stretches, without and with modified EF-P. The structures suggest that the favored conformation of the polyproline-containing nascent chain is incompatible with the peptide exit tunnel of the ribosome and leads to destabilization of the peptidyl-tRNA. Binding of EF-P stabilizes the P-site tRNA, particularly via interactions between its modification and the CCA end, thereby enforcing an alternative conformation of the polyproline-containing nascent chain, which allows a favorable substrate geometry for peptide bond formation.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Fatores de Alongamento de Peptídeos/metabolismo , Peptídeos/metabolismo , Ribossomos/metabolismo , Sítios de Ligação , Microscopia Crioeletrônica , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/ultraestrutura , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutação , Conformação de Ácido Nucleico , Fatores de Alongamento de Peptídeos/química , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/ultraestrutura , Fatores de Iniciação de Peptídeos/química , Fatores de Iniciação de Peptídeos/metabolismo , Peptídeos/química , Ligação Proteica , Biossíntese de Proteínas , Conformação Proteica , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/química , RNA de Transferência/genética , RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Ribossomos/química , Ribossomos/ultraestrutura , Relação Estrutura-Atividade
19.
J Cell Biol ; 216(12): 4123-4139, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29158231

RESUMO

Drp1 is a dynamin guanosine triphosphatase important for mitochondrial and peroxisomal division. Drp1 oligomerization and mitochondrial recruitment are regulated by multiple factors, including interaction with mitochondrial receptors such as Mff, MiD49, MiD51, and Fis. In addition, both endoplasmic reticulum (ER) and actin filaments play positive roles in mitochondrial division, but mechanisms for their roles are poorly defined. Here, we find that a population of Drp1 oligomers is associated with ER in mammalian cells and is distinct from mitochondrial or peroxisomal Drp1 populations. Subpopulations of Mff and Fis1, which are tail-anchored proteins, also localize to ER. Drp1 oligomers assemble on ER, from which they can transfer to mitochondria. Suppression of Mff or inhibition of actin polymerization through the formin INF2 significantly reduces all Drp1 oligomer populations (mitochondrial, peroxisomal, and ER bound) and mitochondrial division, whereas Mff targeting to ER has a stimulatory effect on division. Our results suggest that ER can function as a platform for Drp1 oligomerization, and that ER-associated Drp1 contributes to mitochondrial division.


Assuntos
Retículo Endoplasmático/metabolismo , GTP Fosfo-Hidrolases/genética , Proteínas Associadas aos Microtúbulos/genética , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/genética , Proteínas Mitocondriais/genética , Linhagem Celular Tumoral , Retículo Endoplasmático/ultraestrutura , GTP Fosfo-Hidrolases/antagonistas & inibidores , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/metabolismo , Osteoblastos/metabolismo , Osteoblastos/ultraestrutura , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Multimerização Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
20.
J Hum Genet ; 62(11): 979-988, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29066854

RESUMO

Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are important biomarkers for disease development and progression. To gain insight into the genetic causes of variance in NLR and PLR in the general population, we conducted genome-wide association (GWA) analyses and estimated SNP heritability in a sample of 5901 related healthy Dutch individuals. GWA analyses identified a new genome-wide significant locus on the HBS1L-MYB intergenic region for PLR, which replicated in a sample of 2538 British twins. For platelet count, we replicated three known genome-wide significant loci in our cohort (at CCDC71L-PIK3CG, BAK1 and ARHGEF3). For neutrophil count, we replicated the PSMD3 locus. For the identified top SNPs, we found significant cis and trans expression quantitative trait loci effects for several loci involved in hematological and immunological pathways. Linkage Disequilibrium score (LD) regression analyses for PLR and NLR confirmed that both traits are heritable, with a polygenetic SNP heritability for PLR of 14.1%, and for NLR of 2.4%. Genetic correlations were present between ratios and the constituent counts, with the genetic correlation (r=0.45) of PLR with platelet count reaching statistical significance. In conclusion, we established that two important biomarkers have a significant heritable SNP component, and identified the first genome-wide locus for PLR.


Assuntos
Biomarcadores/sangue , Plaquetas , Proteínas de Ligação ao GTP/genética , Estudo de Associação Genômica Ampla , Proteínas de Choque Térmico HSP70/genética , Fatores de Alongamento de Peptídeos/genética , Locos de Características Quantitativas/genética , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Estudos de Coortes , Feminino , Humanos , Desequilíbrio de Ligação/genética , Linfócitos/metabolismo , Masculino , Neutrófilos/metabolismo , Contagem de Plaquetas , Polimorfismo de Nucleotídeo Único/genética , Complexo de Endopeptidases do Proteassoma/genética , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Proteína Killer-Antagonista Homóloga a bcl-2/genética
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