RESUMEN
BACKGROUND: Cancer screening is effective in reducing the burden of breast, cervical, and colorectal cancers, but not all communities have appropriate access to these services. In this study, we aimed to identify under-resourced communities by assessing the association between the Social Vulnerability Index (SVI) with screening rates for breast, cervical, and colorectal cancers in ZIP-code tabulation areas (ZCTAs) in Rhode Island. METHODS: This study leveraged deidentified health insurance claims data from HealthFacts RI, the state's all-payer claims database, to calculate screening rates for breast, cervical, and colorectal cancers using Healthcare Effectiveness Data and Information Set measures. We used spatial autoregressive Tobit models to assess the association between the SVI, its four domains, and its 15 component variables with screening rates in 2019, accounting for spatial dependencies. RESULTS: In 2019, 73.2, 65.0, and 66.1% of eligible individuals were screened for breast, cervical, and colorectal cancer, respectively. For every 1-unit increase in the SVI, screening rates for breast and colorectal cancer were lower by 0.07% (95% CI 0.01-0.08%) and 0.08% (95% CI 0.02-0.15%), respectively. With higher scores on the SVI's socioeconomic domain, screening rates for all three types of cancers were lower. CONCLUSION: The SVI, especially its socioeconomic domain, is a useful tool for identifying areas that are under-served by current efforts to expand access to screening for breast, cervical, and colorectal cancer. These areas should be prioritized for new place-based partnerships that address barriers to screening at the individual and community level.
Asunto(s)
Neoplasias de la Mama , Neoplasias Colorrectales , Detección Precoz del Cáncer , Neoplasias del Cuello Uterino , Poblaciones Vulnerables , Humanos , Femenino , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Detección Precoz del Cáncer/estadística & datos numéricos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Rhode Island/epidemiología , Persona de Mediana Edad , Masculino , Poblaciones Vulnerables/estadística & datos numéricos , Adulto , Anciano , Factores SocioeconómicosRESUMEN
Toxin-antitoxin (TA) systems are genetic modules composed of a toxin interfering with cellular processes and its cognate antitoxin, which counteracts the activity of the toxin. TA modules are widespread in bacterial and archaeal genomes. It has been suggested that TA modules participate in the adaptation of prokaryotes to unfavorable conditions. The Bosea sp. PAMC 26642 used in this study was isolated from the Arctic lichen Stereocaulon sp. There are 12 putative type II TA loci in the genome of Bosea sp. PAMC 26642. Of these, nine functional TA systems have been shown to be toxic in Escherichia coli The toxin inhibits growth, but this inhibition is reversed when the cognate antitoxin genes are coexpressed, indicating that these putative TA loci were bona fide TA modules. Only the BoVapC1 (AXW83_01405) toxin, a homolog of VapC, showed growth inhibition specific to low temperatures, which was recovered by the coexpression of BoVapB1 (AXW83_01400). Microscopic observation and growth monitoring revealed that the BoVapC1 toxin had bacteriostatic effects on the growth of E. coli and induced morphological changes. Quantitative real time polymerase chain reaction and northern blotting analyses showed that the BoVapC1 toxin had a ribonuclease activity on the initiator tRNAfMet, implying that degradation of tRNAfMet might trigger growth arrest in E. coli Furthermore, the BoVapBC1 system was found to contribute to survival against prolonged exposure at 4°C. This is the first study to identify the function of TA systems in cold adaptation.
Asunto(s)
Antitoxinas/metabolismo , Toxinas Bacterianas/metabolismo , Bradyrhizobiaceae/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , ARN de Transferencia de Metionina/metabolismo , Sistemas Toxina-Antitoxina/genética , Antitoxinas/genética , Proteínas Bacterianas , Toxinas Bacterianas/genética , Bradyrhizobiaceae/genética , Bradyrhizobiaceae/aislamiento & purificación , Bradyrhizobiaceae/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Líquenes/fisiología , Operón , Regiones Promotoras GenéticasRESUMEN
This manuscript presents a self-interferometric phase analysis technique for sea surface observation using a single scatterometer system. The self-interferometric phase is proposed to complement the imprecise analysis results due to the very meager signal strength measured at a high incident angle of more than 30°, which is a vulnerability of the existing analysis method using the Doppler frequency based on the backscattered signal strength. Moreover, compared to conventional interferometry, it is characterized by the phase-based analysis using consecutive signals from a single scatterometer system without any auxiliary system or channel. To apply the interferometric signal process on the moving sea surface observation, it is necessary to secure a reference target; however, this is hard to solve in practice. Hence, we adopted the back-projection algorithm to project the radar signals onto a fixed reference position above the sea surface, where the theoretical model for extracting the self-interferometric phase was derived from the radar-received signal model applying the back-projection algorithm. The observation performance of the proposed method was verified using the raw data collected at the Ieodo Ocean Research Station in Republic of Korea. In the observation result for wind velocity at the high incident angles of 40° and 50°, the self-interferometric phase analysis technique shows a better performance of a correlation coefficient of more than about 0.779 and an RMSE (root-mean-square error) of about 1.69 m/s compared to the existing method of a correlation coefficient of less than 0.62 and RMSE of more than 2.46 m/s.
RESUMEN
Abscisic acid (ABA) plays an important role in seed germination, stomatal closure, and seedling growth inhibition in plants. Among downstream genes whose expression levels are regulated by AFA1 (Arabidopsis F-box Protein Hypersensitive to ABA 1), one gene, AtHAD1 upregulated by ABA was selected from Arabidopsis. AtHAD1 was induced by drought and salt stresses as well as by ABA and was found in dry seeds. Its loss-of-function mutants exhibited increased ABA-sensitivity in germination, seedling growth, and stomatal closure. In addition, the mutants displayed a lower water loss rate and higher survival rate under drought stress than the wild-type plants, indicating that a loss of AtHAD1 leads to enhanced drought tolerance. These results show that AtHAD1 has an inhibitory role in the ABA response and ABA-mediated drought tolerance. The expression levels of several ABA-responsive genes in athad1 were higher than those in the wild-type under the ABA treatment, suggesting that AtHAD1, as a negative regulator in the ABA response, could be associated with the downregulation of the ABA-responsive genes. The phosphatase assay showed that AtHAD1 exhibits phosphatase activity. Monitoring of the subcellular localization of GFP-fused AtHAD1 proteins indicated that AtHAD1 exists in the nucleus and cytoplasm. Overall, this study shows that Arabidopsis HAD1 as an intracellular phosphatase negatively functions in the ABA-mediated cellular responses. This research could serve as a research basis to understand the functional link between ABA signaling and the regulation process of the cellular phosphate level.
Asunto(s)
Ácido Abscísico/farmacología , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Hidrolasas/genética , Monoéster Fosfórico Hidrolasas/genética , Reguladores del Crecimiento de las Plantas/farmacología , Ácido Abscísico/metabolismo , Adaptación Fisiológica/genética , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Germinación/efectos de los fármacos , Germinación/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Hidrolasas/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/genética , Estomas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Salinidad , Plantones/efectos de los fármacos , Plantones/genética , Plantones/metabolismo , Semillas/efectos de los fármacos , Semillas/genética , Semillas/metabolismo , Transducción de Señal , Estrés FisiológicoRESUMEN
A multifunctional scatterometer system and optimized radar signal processing for simultaneous observation of various physical oceanographic parameters are described in this paper. Existing observation methods with microwave remote sensing techniques generally use several separate systems such as scatterometer, altimeter, and Doppler radar for sea surface monitoring, which are inefficient in system operation and cross-analysis of each observation data. To improve this point, we integrated separate measurement functions into a single observation system by adding a measurement function of Doppler frequency to the existing system. So it enables to simultaneously measure the range and polarimetric responses of backscattering as well as movements of the sea surface. Here, the simultaneous measurement function of Doppler frequency was implemented by sampling an FMCW (frequency modulated continuous wave) radar signal as 2D raw data consisting of fast- and slow-time samples, i.e., the range and backscattering of radar target signals are analyzed from the fast-time samples while the Doppler frequency by the radar target's movement extracts from the slow-time samples. Through the Fourier transformed-based range-Doppler signal process, distance (R), backscattering (σ°), and Doppler frequency (fD) are sequentially extracted from the 2D raw data, and a correlation to the physical oceanographic parameters is analyzed. Operability of the proposed system was examed through total 3 times of field campaigns from June 2017 to August 2020 and the observation data retrieved by the radar measurement data (R, σ°, fD) was also cross-analyzed with in-situ data: e.g., tide, significant wave height, and wind speed and direction. Differences in the comparative results as an observational accuracy are as follows. Tidal level (Root Mean Square Error 0.169 m (R)), significant wave height (RMSE 0.127 m (R), 0.362 m (σ°)), wind speed (RMSE 1.880 m/s (fD), 2.094 m/s (σ°)) and direction (18.84° (fD)).
RESUMEN
Mycobacterium smegmatis has two isocitrate lyase (ICL) isozymes (MSMEG_0911 and MSMEG_3706). We demonstrated that ICL1 (MSMEG_0911) is the predominantly expressed ICL in M. smegmatis and plays a major role in growth on acetate or fatty acid as the sole carbon and energy source. Expression of the icl1 gene in M. smegmatis was demonstrated to be strongly upregulated during growth on acetate relative to that in M. smegmatis grown on glucose. Expression of icl1 was shown to be positively regulated by the RamB activator, and three RamB-binding sites (RamBS1, RamBS2, and RamBS3) were identified in the upstream region of icl1 using DNase I footprinting analysis. Succinyl coenzyme A (succinyl-CoA) was shown to increase the affinity of binding of RamB to its binding sites and enable RamB to bind to RamBS2, which is the most important site for RamB-mediated induction of icl1 expression. These results suggest that succinyl-CoA serves as a coinducer molecule for RamB. Our study also showed that cAMP receptor protein (Crp1; MSMEG_6189) represses icl1 expression in M. smegmatis grown in the presence of glucose. Therefore, the strong induction of icl1 expression during growth on acetate as the sole carbon source relative to the weak expression of icl1 during growth on glucose is likely to result from combined effects of RamB-mediated induction of icl1 in the presence of acetate and Crp-mediated repression of icl1 in the presence of glucose. IMPORTANCE Carbon flux through the glyoxylate shunt has been suggested to affect virulence, persistence, and antibiotic resistance of Mycobacterium tuberculosis. Therefore, it is important to understand the precise mechanism underlying the regulation of the icl gene encoding the key enzyme of the glyoxylate shunt. Using Mycobacterium smegmatis, this study revealed the regulation mechanism underlying induction of icl1 expression in M. smegmatis when the glyoxylate shunt is required. The conservation of the cis- and trans-acting regulatory elements related to icl1 regulation in both M. smegmatis and M. tuberculosis implies that a similar regulatory mechanism operates for the regulation of icl1 expression in M. tuberculosis.
Asunto(s)
Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Isocitratoliasa/metabolismo , Mycobacterium smegmatis/metabolismo , Proteínas Bacterianas/genética , Ácidos Grasos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Glucosa/farmacología , Isocitratoliasa/genética , Isoenzimas , Mycobacterium smegmatis/genéticaRESUMEN
ABA is a phytohormone involved in diverse plant events such as seed germination and drought response. An F-box protein functions as a substrate receptor of the SCF complex and is responsible for ubiquitination of target proteins, triggering their subsequent degradation mediated by ubiquitin proteasome system. Here, we have isolated a gene named ARABIDOPSIS F-BOX PROTEIN HYPERSENSITIVE TO ABA 1 (AFA1) that was upregulated by ABA. AFA1 interacted with adaptor proteins of the SCF complex, implying its role as a substrate receptor of the complex. Its loss of function mutants, afa1 seedlings, exhibited ABA-hypersensitivity, including delayed germination in the presence of ABA. Moreover, loss of AFA1 led to increased drought tolerance in adult plants. Microarray data with ABA treatments indicated that 129 and 219 genes were upregulated or downregulated, respectively, by more than three times in afa1 relative to the wild type. Among the upregulated genes in afa1, the expression of 28.7% was induced by more than three times in the presence of ABA, while only 9.3% was repressed to the same extent. These data indicate that AFA1 is involved in the downregulation of many ABA-inducible genes, in accordance with the ABA-hypersensitive phenotype of afa1. Epistasis analysis showed that AFA1 could play a role upstream of ABI4 and ABI5 in the ABA signaling for germination inhibition. Collectively, our findings suggest that AFA1 is a novel F-box protein that negatively regulates ABA signaling.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Ácido Abscísico/farmacología , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequías , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Mutación , Semillas/metabolismoRESUMEN
A sea surface imaging technique for an emergency response using a ready-made frequency modulated continuous wave-synthetic aperture radar (FMCW SAR) system and its experimental results are described in this paper. The optimal range of radiowave incidence angle for sea surface imaging was analyzed by a theoretical scattering model and measurement data, and it was properly applied to the FMCW SAR system by readjusting the delayed-dechirp process. Raw data acquired through flight experiments were reconstructed to SAR image by the range-doppler algorithm. To verify the performance of the reconstructed sea surface image, dual-channel images collected by the configuration of the along-track interferometry were used, and then performance indicators such as signal attenuation, coherence, and phase difference were analyzed. Through this experimental study, it was confirmed that the ready-made FMCW SAR system without a function of the incident angle control can also conduct limited missions for maritime observation. It is possible to be an alternative resource for emergency response, in which the cases are requiring urgent maritime disaster detection and analysis.
RESUMEN
BPI-inducible protein A (BipA) is a conserved ribosome-associated GTPase in bacteria that is structurally similar to other GTPases associated with protein translation, including IF2, EF-Tu, and EF-G. Its binding site on the ribosome appears to overlap those of these translational GTPases. Mutations in the bipA gene cause a variety of phenotypes, including cold and antibiotics sensitivities and decreased pathogenicity, implying that BipA may participate in diverse cellular processes by regulating translation. According to recent studies, a bipA-deletion strain of Escherichia coli displays a ribosome assembly defect at low temperature, suggesting that BipA might be involved in ribosome assembly. To further investigate BipA's role in ribosome biogenesis, here, we compared and analyzed the ribosomal protein compositions of MG1655 WT and bipA-deletion strains at 20 °C. Aberrant 50S ribosomal subunits (i.e. 44S particles) accumulated in the bipA-deletion strain at 20 °C, and the ribosomal protein L6 was absent in these 44S particles. Furthermore, bipA expression was significantly stimulated at 20 °C, suggesting that it encodes a cold shock-inducible GTPase. Moreover, the transcriptional regulator cAMP receptor protein (CRP) positively promoted bipA expression only at 20 °C. Importantly, GFP and α-glucosidase refolding assays revealed that BipA has chaperone activity. Our findings indicate that BipA is a cold shock-inducible GTPase that participates in 50S ribosomal subunit assembly by incorporating the L6 ribosomal protein into the 44S particle during the assembly.
Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimología , GTP Fosfohidrolasas/metabolismo , Regulación Bacteriana de la Expresión Génica , Chaperonas Moleculares/metabolismo , Fosfoproteínas/metabolismo , Subunidades Ribosómicas Grandes Bacterianas/metabolismo , Frío , Proteína Receptora de AMP Cíclico/genética , Proteína Receptora de AMP Cíclico/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , GTP Fosfohidrolasas/genética , Chaperonas Moleculares/genética , Fosfoproteínas/genética , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas Grandes Bacterianas/genéticaAsunto(s)
Vitíligo , Humanos , Pronóstico , Estudios Retrospectivos , Vitíligo/diagnóstico , Vitíligo/patologíaRESUMEN
UNLABELLED: The unique Escherichia coli GTPase Der (double Era-like GTPase), which contains tandemly repeated GTP-binding domains, has been shown to play an essential role in 50S ribosomal subunit biogenesis. The depletion of Der results in the accumulation of precursors of 50S ribosomal subunits that are structurally unstable at low Mg(2+) concentrations. Der homologs are ubiquitously found in eubacteria. Conversely, very few are conserved in eukaryotes, and none is conserved in archaea. In the present study, to verify their conserved role in bacterial 50S ribosomal subunit biogenesis, we cloned Der homologs from two gammaproteobacteria, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium; two pathogenic bacteria, Staphylococcus aureus and Neisseria gonorrhoeae; and the extremophile Deinococcus radiodurans and then evaluated whether they could functionally complement the E. coli der-null phenotype. Only K. pneumoniae and S Typhimurium Der proteins enabled the E. coli der-null strain to grow under nonpermissive conditions. Sucrose density gradient experiments revealed that the expression of K. pneumoniae and S Typhimurium Der proteins rescued the structural instability of 50S ribosomal subunits, which was caused by E. coli Der depletion. To determine what allows their complementation, we constructed Der chimeras. We found that only Der chimeras harboring both the linker and long C-terminal regions could reverse the growth defects of the der-null strain. Our findings suggest that ubiquitously conserved essential GTPase Der is involved in 50S ribosomal subunit biosynthesis in various bacteria and that the linker and C-terminal regions may participate in species-specific recognition or interaction with the 50S ribosomal subunit. IMPORTANCE: In Escherichia coli, Der (double Era-like GTPase) is an essential GTPase that is important for the production of mature 50S ribosomal subunits. However, to date, its precise role in ribosome biogenesis has not been clarified. In this study, we used five Der homologs from gammaproteobacteria, pathogenic bacteria, and an extremophile to elucidate their conserved function in 50S ribosomal subunit biogenesis. Among them, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium Der homologs implicated the participation of Der in ribosome assembly in E. coli Our results show that the linker and C-terminal regions of Der homologs are correlated with its functional complementation in E. coli der mutants, suggesting that they are involved in species-specific recognition or interaction with 50S ribosomal subunits.
Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas de Unión al GTP/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Secuencia de Aminoácidos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Evolución Molecular , Proteínas de Unión al GTP/genética , Prueba de Complementación Genética , Mutación , Especificidad de la EspecieRESUMEN
Here, we report a resistance mechanism that is induced through the modulation of 16S ribosomal RNA (rRNA) processing on the exposure of Escherichia coli cells to aminoglycoside antibiotics. We observed decreased expression levels of RNase G associated with increased RNase III activity on rng mRNA in a subgroup of E. coli isolates that transiently acquired resistance to low levels of kanamycin or streptomycin. Analyses of 16S rRNA from the aminoglycoside-resistant E. coli cells, in addition to mutagenesis studies, demonstrated that the accumulation of 16S rRNA precursors containing 3-8 extra nucleotides at the 5' terminus, which results from incomplete processing by RNase G, is responsible for the observed aminoglycoside resistance. Chemical protection, mass spectrometry analysis and cell-free translation assays revealed that the ribosomes from rng-deleted E. coli have decreased binding capacity for, and diminished sensitivity to, streptomycin and neomycin, compared with wild-type cells. It was observed that the deletion of rng had similar effects in Salmonella enterica serovar Typhimurium strain SL1344. Our findings suggest that modulation of the endoribonucleolytic activity of RNase III and RNase G constitutes a previously uncharacterized regulatory pathway for adaptive resistance in E. coli and related gram-negative bacteria to aminoglycoside antibiotics.
Asunto(s)
Aminoglicósidos/farmacología , Antibacterianos/farmacología , Endorribonucleasas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos , Inhibidores de la Síntesis de la Proteína/farmacología , ARN Ribosómico 16S/metabolismo , Ribonucleasa III/metabolismo , Aminoglicósidos/metabolismo , Antibacterianos/metabolismo , Farmacorresistencia Bacteriana , Endorribonucleasas/genética , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Biosíntesis de Proteínas/efectos de los fármacos , Inhibidores de la Síntesis de la Proteína/metabolismo , Precursores del ARN/química , Precursores del ARN/metabolismo , Procesamiento Postranscripcional del ARN , ARN Ribosómico 16S/química , Subunidades Ribosómicas Pequeñas Bacterianas/metabolismo , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genéticaRESUMEN
CspA has been identified as a major cold-shock protein in Escherichia coli. CspA binds to RNAs which are abnormally folded at low temperature and then acts as an RNA chaperone unfolding those RNAs. The dramatic expression of cspA at low temperature is contributed by posttranscriptional stability and robust translatability. Interestingly, when cspA mRNA encoding a premature nonsense codon was overexpressed at low temperature, cell growth was completely inhibited. This phenotype was termed LACE (the low temperature-dependent antibiotic effect of truncated cspA expression), and this lethality resulted from exclusive stalling of most ribosomes on mutant cspA mRNAs. In a previous study, we demonstrated that overexpression of the ATP-dependent DNA helicases, UvrD and DinG, suppressed the lethality and ribosome stalling caused by mutant cspA mRNA. In the present study, we attempted to elucidate how these two DNA helicases help recover normal growth under LACE condition. Interestingly, we found that UvrD and DinG appeared to have an ability to down-regulate the replication of pUC-based high copy plasmid. In plasmid copy number tests, the amount of pUC-based plasmid encoding mutant cspA was reduced by 3-10-fold when either UvrD or DinG was expressed. Through a ß-galactosidase activity assay, we also confirmed that expression of the lacZα gene inserted into the pUC-based plasmid was significantly reduced due to down-regulation of plasmid replication. Our findings imply that UvrD and DinG, known as non-replicative helicases, play a novel role in the regulation of ColE1-like plasmid replication.
Asunto(s)
Proteínas Bacterianas/genética , ADN Helicasas/genética , Replicación del ADN , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Plásmidos/genética , Clonación Molecular , ADN Helicasas/metabolismo , Activación Enzimática , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión GénicaRESUMEN
This study investigated protein characteristics and physiological functions of DER (Double Era-like GTPase) of higher plants. Nicotiana benthamiana DER (NbDER) contained two tandemly repeated GTP-binding domains (GD) and a C-terminal domain (CTD) that was similar to the K-homology domain involved in RNA binding. Both GDs possessed GTPase activity and contributed to the maximum GTPase activity of NbDER. NbDER fused to green fluorescent protein was localized primarily to chloroplast nucleoids. Arabidopsis der null mutants exhibited an embryonic lethal phenotype, indicating an essential function of DER during plant embryogenesis. Virus-induced gene silencing of NbDER resulted in a leaf-yellowing phenotype caused by disrupted chloroplast biogenesis. NbDER was associated primarily with the chloroplast 50S ribosomal subunit in vivo, and both the CTD and the two GD contributed to the association. Recombinant proteins of NbDER and its CTD could bind to 23S and 16S ribosomal RNAs in vitro. Depletion of NbDER impaired processing of plastid-encoded ribosomal RNAs, resulting in accumulation of the precursor rRNAs in the chloroplasts. NbDER-deficient chloroplasts contained significantly reduced levels of mature 23S and 16S rRNAs and diverse mRNAs in the polysomal fractions, suggesting decreased translation in chloroplasts. These results suggest that DER is involved in chloroplast rRNA processing and ribosome biogenesis in higher plants.
Asunto(s)
GTP Fosfohidrolasas/metabolismo , Nicotiana/enzimología , Procesamiento Postranscripcional del ARN , ARN Ribosómico/metabolismo , Ribosomas/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , GTP Fosfohidrolasas/genética , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Técnicas de Inactivación de Genes , Silenciador del Gen , Mutagénesis Insercional , Fenotipo , Hojas de la Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estructura Terciaria de Proteína , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , ARN Ribosómico/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Proteínas Recombinantes de Fusión , Ribosomas/genética , Nicotiana/citología , Nicotiana/genéticaRESUMEN
As part of our chemical screening program for new microbial secondary metabolites, we discovered a new compound, JBIR-107 (1), from the culture of Streptomyces tateyamensis NBRC 105047 isolated from a marine sponge sample. Extensive NMR and MS spectroscopic data enabled the structure of 1 to be determined as 5-acetamido-6-(4-(methyl(2-oxo-3-phenylpropyl)amino)phenyl)-4-oxohexanoic acid.
Asunto(s)
Acetamidas/aislamiento & purificación , Acetamidas/metabolismo , Organismos Acuáticos/microbiología , Caproatos/aislamiento & purificación , Caproatos/metabolismo , Poríferos/microbiología , Streptomyces/metabolismo , Acetamidas/química , Animales , Caproatos/química , Fermentación , Streptomyces/aislamiento & purificaciónRESUMEN
The BipA protein is a universally conserved GTPase in bacterial species and is structurally similar to translational GTPases. Despite its wide distribution, BipA is dispensable for growth under optimal growth conditions but is required under stress conditions. In particular, bipA-deleted cells (ESC19) have been shown to display a variety of phenotypic changes in ribosome assembly, capsule production, lipopolysaccharide (LPS) synthesis, biofilm formation, and motility at low temperature, suggesting its global regulatory roles in cold adaptation. Here, through genomic library screening, we found a suppressor clone containing nhaR, which encodes a Na+-responsive LysR-type transcriptional regulator and whose gene product partially restored the growth of strain ESC19 at 20°C. The suppressed cells showed slightly reduced capsule production and improved biofilm-forming ability at 20°C, whereas the defects in the LPS core and swimming motility were not restored but aggravated by overexpression of nhaR. Notably, the overexpression partially alleviated the defects in 50S ribosomal subunit assembly and rRNA processing of ESC19 cells by enhancing the overall transcription of rRNA. Electrophoretic mobility shift assay revealed the association of NhaR with the promoter of seven rrn operons, suggesting that NhaR directly regulates rRNA transcription in ESC19 at 20°C. The suppressive effects of NhaR on ribosomes, capsules, and LPS were dependent on its DNA-binding activity, implying that NhaR might be a transcriptional factor involved in regulating these genes at 20°C. Furthermore, we found that BipA may be involved in adaptation to salt stress, designating BipA as a global stress-responsive regulator, as the deletion of bipA led to growth defects at 37°C and high Na+ concentrations without ribosomal defects.
RESUMEN
New 34-membered polyol macrolides JBIR-129 (1) and JBIR-139 (2) were isolated from the culture of the terrestrial Streptomyces RK74. The planar structures of 1 and 2 were established on the basis of 1D and 2D NMR, ESI-TOF-MS, IR, and UV spectra. The relative configurations of the sugar units were determined by analyzing vicinal ¹H-¹H coupling constants and steric information. Both 1 and 2 showed cytotoxic activity against human ovarian adenocarcinoma SKOV-3 cells with IC50 values of 0.3 and 0.4 µM, respectively.
Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Macrólidos/aislamiento & purificación , Macrólidos/farmacología , Streptomyces/química , Antineoplásicos/química , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Concentración 50 Inhibidora , Japón , Macrólidos/química , Estructura Molecular , Resonancia Magnética Nuclear BiomolecularRESUMEN
Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is an enzyme that catalyzes hydrolysis of 3'-phosphotyrosyl bonds and is involved in repair of irreversible topoisomerase I (Top1)-DNA covalent complexes. Tdp1 inhibitors are regarded as potential cancer therapeutics in combination with Top1 inhibitors, which are currently used to treat human cancers. While screening for Tdp1 inhibitors, we discovered a novel compound, JBIR-21 (1), from the culture of an anamorphic fungus, RF-13305. The structure of 1 was established by extensive NMR and MS analyses. Compound 1 showed inhibitory activity against Tdp1 (IC(50) value, 18 µM) and cytotoxic activity against cancer cell lines (IC(50) values, 3.5-13 µM). Compound 1 also exhibited antitumor activity in a mouse xenograft model without adverse effects.
Asunto(s)
Hongos/química , Hidrolasas Diéster Fosfóricas/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Animales , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Estructura Molecular , Sesquiterpenos/químicaRESUMEN
The aim of this study was to investigate whether individualized low-intensity exercise (ILIE) within the recovery domain before lactate threshold 1 (LT 1) improves energetic recovery and general endurance capacity in professional soccer players. Twenty-four professional soccer players (age: 24.53 ± 4.85 years, height: 180 ± 6.30 cm, body mass: 75.86 ± 8.01 kg, body fat: 12.19 ± 2.69%) participated in the study (n = 24). The 1-h ILIE intervention involved 27 jogging sessions spanning nine weeks and jogging speed corresponding to 72% of LT 1 (7.15 ± 0.95 kmâh-1). Pre-ILIE and post-ILIE LT testing variables measured within 9 weeks included blood lactate concentrations (La-) and heart rate (HR) at specific exercise intensities during ILIE LT test. The jogging/running speeds (S), delta (Δ) S, HR, and ΔHR were measured at 1.5, 2.0, 3.0, and 4.0 mmolâL-1 La-, respectively. Values of La- and HR at the same exercise intensities (5.4-16.2 kmâh-1) in the post-ILIE LT test compared with pre-ILIE LT test were significantly decreased (P < 0.05 and P < 0.01, respectively). Furthermore, S at all specific La- levels (1.5, 2.0, 3.0, and 4.0) were significantly increased, while HR at 2.0, 3.0, and 4.0 La- decreased significantly (P < 0.05 and P < 0.01, respectively). Low to moderate positive correlations were observed between ΔS and ΔHR at 1.5 and 2.0 La- (r = 0.52 and r = 0.40, respectively). The nine-week ILIE improved energy recovery and general endurance of professional soccer players. This relates to repeated high-intensity intermittent sprints during the 90-min soccer game.
Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Adulto , Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Prueba de Esfuerzo , Humanos , Ácido Láctico , Carrera/fisiología , Fútbol/fisiología , Adulto JovenRESUMEN
Toxin-antitoxin (TA) systems are growth-controlling genetic elements consisting of an intracellular toxin protein and its cognate antitoxin. TA systems have been spread among microbial genomes through horizontal gene transfer and are now prevalent in most bacterial and archaeal genomes. Under normal growth conditions, antitoxins tightly counteract the activity of the toxins. Upon stresses, antitoxins are inactivated, releasing activated toxins, which induce growth arrest or cell death. In this study, among nine functional TA modules in Bosea sp. PAMC 26642 living in Arctic lichen, we investigated the functionality of BoHigBA2. BohigBA2 is located close to a genomic island and adjacent to flagellar gene clusters. The expression of BohigB2 induced the inhibition of E. coli growth at 37°C, which was more manifest at 18°C, and this growth defect was reversed when BohigA2 was co-expressed, suggesting that this BoHigBA2 module might be an active TA module in Bosea sp. PAMC 26642. Live/dead staining and viable count analyses revealed that the BoHigB2 toxin had a bactericidal effect, causing cell death. Furthermore, we demonstrated that BoHigB2 possessed mRNA-specific ribonuclease activity on various mRNAs and cleaved only mRNAs being translated, which might impede overall translation and consequently lead to cell death. Our study provides the insight to understand the cold adaptation of Bosea sp. PAMC 26642 living in the Arctic.