723 research outputs found

    Gestión administrativa y gestión documental del archivo en la municipalidad distrital de Mancos, 2022

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    En la investigación que se muestra a continuación, se planteó como objetivo general determinar la relación entre gestión administrativa y gestión documental del archivo en la Municipalidad distrital de Mancos, 2022. La investigación realizada fue de tipo básica, su nivel fue correlacional, con diseño no experimental de corte transversal y con un enfoque cuantitativo. Así mismo la población de estudio que fue conformada por los 30 trabajadores de dicha Municipalidad, quienes colaboraron para hacer la medición de nuestras variables, por medio de la aplicación de un cuestionario, cuyas primeras 16 preguntas nos ayudaron a medir la variable gestión administrativa y las 16 posteriores para medir la segunda variable como es la gestión documental del archivo. De igual forma mediante la aplicación del estadístico Rho de Spearman que fue utilizado para obtención de los resultados entre ellos el nivel de correlación entre las dos variables, donde se concluyó que si existe una relación positiva y significativa de 0,773 y p = 0,000<0.0

    Turnip mosaic potyvirus probably first spread to Eurasian brassica crops from wild orchids about 1000 years ago

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    Turnip mosaic potyvirus (TuMV) is probably the most widespread and damaging virus that infects cultivated brassicas worldwide. Previous work has indicated that the virus originated in western Eurasia, with all of its closest relatives being viruses of monocotyledonous plants. Here we report that we have identified a sister lineage of TuMV-like potyviruses (TuMV-OM) from European orchids. The isolates of TuMV-OM form a monophyletic sister lineage to the brassica-infecting TuMVs (TuMV-BIs), and are nested within a clade of monocotyledon-infecting viruses. Extensive host-range tests showed that all of the TuMV-OMs are biologically similar to, but distinct from, TuMV-BIs and do not readily infect brassicas. We conclude that it is more likely that TuMV evolved from a TuMV-OM-like ancestor than the reverse. We did Bayesian coalescent analyses using a combination of novel and published sequence data from four TuMV genes [helper component-proteinase protein (HC-Pro), protein 3(P3), nuclear inclusion b protein (NIb), and coat protein (CP)]. Three genes (HC-Pro, P3, and NIb), but not the CP gene, gave results indicating that the TuMV-BI viruses diverged from TuMV-OMs around 1000 years ago. Only 150 years later, the four lineages of the present global population of TuMV-BIs diverged from one another. These dates are congruent with historical records of the spread of agriculture in Western Europe. From about 1200 years ago, there was a warming of the climate, and agriculture and the human population of the region greatly increased. Farming replaced woodlands, fostering viruses and aphid vectors that could invade the crops, which included several brassica cultivars and weeds. Later, starting 500 years ago, inter-continental maritime trade probably spread the TuMV-BIs to the remainder of the world

    Cohesin-independent STAG proteins interact with RNA and localise to R-loops to promote complex loading

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    Most studies of cohesin function consider the Stromalin Antigen (STAG/SA) proteins as core complex members given their ubiquitous interaction with the cohesin ring. Here, we provide functional data to support the notion that the SA subunit is not a mere passenger in this structure, but instead plays a key role in the localization of cohesin to diverse biological processes and promotes loading of the complex at these sites. We show that in cells acutely depleted for RAD21, SA proteins remain bound to chromatin, cluster in 3D and interact with CTCF, as well as with a wide range of RNA binding proteins involved in multiple RNA processing mechanisms. Accordingly, SA proteins interact with RNA and are localised to R-loops where they contribute to R-loop regulation. Our results place SA1 within R-loop domains upstream of the cohesin complex and reveal a role for SA1 in cohesin loading which is independent of NIPBL, the canonical cohesin loader. We propose that SA1 takes advantage of structural R-loop platforms to link cohesin loading and chromatin structure with diverse functions. Since SA proteins are pan-cancer targets, and R-loops play an increasingly prevalent role in cancer biology, our results have important implications for the mechanistic understanding of SA proteins in cancer and disease

    Cohesin-independent STAG proteins interact with RNA and R-loops and promote complex loading

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    Most studies of cohesin function consider the Stromalin Antigen (STAG/SA) proteins as core complex members given their ubiquitous interaction with the cohesin ring. Here, we provide functional data to support the notion that the SA subunit is not a mere passenger in this structure, but instead plays a key role in the localization of cohesin to diverse biological processes and promotes loading of the complex at these sites. We show that in cells acutely depleted for RAD21, SA proteins remain bound to chromatin, cluster in 3D and interact with CTCF, as well as with a wide range of RNA binding proteins involved in multiple RNA processing mechanisms. Accordingly, SA proteins interact with RNA, RNA binding proteins and R-loops, even in the absence of cohesin. Our results place SA1 on chromatin upstream of the cohesin ring and reveal a role for SA1 in cohesin loading which is independent of NIPBL, the canonical cohesin loader. We propose that SA1 takes advantage of structural R-loop platforms to link cohesin loading and chromatin structure with diverse functions. Since SA proteins are pan-cancer targets, and R-loops play an increasingly prevalent role in cancer biology, our results have important implications for the mechanistic understanding of SA proteins in cancer and disease

    VHL-P138R and VHL-L163R Novel Variants: Mechanisms of VHL Pathogenicity Involving HIF-Dependent and HIF-Independent Actions

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    The von Hippel–Lindau (VHL) disease is an autosomal dominant cancer syndrome caused by mutations in the VHL tumor suppressor gene. VHL protein (pVHL) forms a complex (VBC) with Elongins B-C, Cullin2, and Rbx1. Although other functions have been discovered, the most described function of pVHL is to recognize and target hypoxia-inducible factor (HIF) for degradation. This work comprises the functional characterization of two novel variants of the VHL gene (P138R and L163R) that have been described in our center in patients with VHL disease by in vitro, in vivo, and in silico approaches. In vitro, we found that these variants have a significantly shorter half-life compared to wild-type VHL but still form a functional VBC complex. Altered fibronectin deposition was evidenced for both variants using immunofluorescence. In vivo studies revealed that both variants failed to suppress tumor growth. By means of molecular dynamics simulations, we inspected in silico the nature of the changes introduced by each variant in the VBC complex. We have demonstrated the pathogenicity of P138R and L163R novel variants, involving HIF-dependent and HIF-independent mechanisms. These results provide the basis for future studies regarding the impact of structural alterations on posttranslational modifications that drive pVHL’s fate and functions.Fil: Mathó Pacielo, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Fernández, María Celia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Bonanata, Jenner. Universidad de la República; UruguayFil: Liu, Xian-De. Md Anderson Cancer Center ; University Of Texas;Fil: Martin, Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Vieites, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Sanso, Elsa Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Barontini, Marta Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Jonasch, Eric. Md Anderson Cancer Center ; University Of Texas;Fil: Coitiño, E. Laura. Universidad de la Republica; UruguayFil: Pennisi, Patricia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentin

    Epstein-Barr virus transcription factor Zta acts through distal regulatory elements to directly control cellular gene expression

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    Lytic replication of the human gamma herpes virus Epstein-Barr virus (EBV) is an essential prerequisite for the spread of the virus. Differential regulation of a limited number of cellular genes has been reported in B-cells during the viral lytic replication cycle. We asked whether a viral bZIP transcription factor, Zta (BZLF1, ZEBRA, EB1), drives some of these changes. Using genome-wide chromatin immunoprecipitation coupled to next-generation DNA sequencing (ChIP-seq) we established a map of Zta interactions across the human genome. Using sensitive transcriptome analyses we identified 2263 cellular genes whose expression is significantly changed during the EBV lytic replication cycle. Zta binds 278 of the regulated genes and the distribution of binding sites shows that Zta binds mostly to sites that are distal to transcription start sites. This differs from the prevailing view that Zta activates viral genes by binding exclusively at promoter elements. We show that a synthetic Zta binding element confers Zta regulation at a distance and that distal Zta binding sites from cellular genes can confer Zta-mediated regulation on a heterologous promoter. This leads us to propose that Zta directly reprograms the expression of cellular genes through distal elements

    Does increasing treatment frequency address sub-optimal responses to ivermectin for the control and elimination of river blindness?

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    Background Several African countries have adopted a biannual ivermectin distribution strategy in some foci to control and eliminate onchocerciasis. In 2010, the Ghana Health Service started biannual distribution to combat transmission hotspots and sub-optimal responses to treatment. We assessed the epidemiological impact of the first 3 years of this strategy and quantified responses to ivermectin over two consecutive rounds of treatment in 10 sentinel communities. Methods We evaluated Onchocerca volvulus microfilarial intensity and prevalence in those aged +/-20 years before the first, second and fifth (or sixth) biannual treatment rounds using skin snip data from 956 participants. We used longitudinal regression modelling to estimate rates of microfilarial repopulation of the skin in a cohort of 217 participants who were followed-up over the first two rounds of biannual treatment. Results Biannual treatment has had a positive impact, with substantial reductions in infection intensity after 4 or 5 rounds in most communities. We identified three communities—all having been previously recognised as responding sub-optimally to ivermectin—with statistically significantly high microfilarial repopulation rates. We did not find any clear association between microfilarial repopulation rate and the number of years of prior intervention, coverage, or the community level of infection. Conclusions The strategy of biannual ivermectin treatment in Ghana has reduced O. volvulus microfilarial intensity and prevalence, but sub-optimal responses to treatment remain evident in a number of previously and consistently implicated communities. Whether increasing the frequency of treatment will be sufficient to meet the World Health Organization’s 2020 elimination goals remains uncertain

    The RING-CH ligase K5 antagonizes restriction of KSHV and HIV-1 particle release by mediating ubiquitin-dependent endosomal degradation of tetherin

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    Tetherin (CD317/BST2) is an interferon-induced membrane protein that inhibits the release of diverse enveloped viral particles. Several mammalian viruses have evolved countermeasures that inactivate tetherin, with the prototype being the HIV-1 Vpu protein. Here we show that the human herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) is sensitive to tetherin restriction and its activity is counteracted by the KSHV encoded RING-CH E3 ubiquitin ligase K5. Tetherin expression in KSHV-infected cells inhibits viral particle release, as does depletion of K5 protein using RNA interference. K5 induces a species-specific downregulation of human tetherin from the cell surface followed by its endosomal degradation. We show that K5 targets a single lysine (K18) in the cytoplasmic tail of tetherin for ubiquitination, leading to relocalization of tetherin to CD63-positive endosomal compartments. Tetherin degradation is dependent on ESCRT-mediated endosomal sorting, but does not require a tyrosine-based sorting signal in the tetherin cytoplasmic tail. Importantly, we also show that the ability of K5 to substitute for Vpu in HIV-1 release is entirely dependent on K18 and the RING-CH domain of K5. By contrast, while Vpu induces ubiquitination of tetherin cytoplasmic tail lysine residues, mutation of these positions has no effect on its antagonism of tetherin function, and residual tetherin is associated with the trans-Golgi network (TGN) in Vpu-expressing cells. Taken together our results demonstrate that K5 is a mechanistically distinct viral countermeasure to tetherin-mediated restriction, and that herpesvirus particle release is sensitive to this mode of antiviral inhibition
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