122 research outputs found
A cytoplasm-specific activity encoded by the Trithorax-like ATX1 gene
Eukaryotes produce multiple products from a single gene locus by alternative splicing, translation or promoter usage as mechanisms expanding the complexity of their proteome. Trithorax proteins, including the Arabidopsis Trithorax-like protein ATX1, are histone modifiers regulating gene activity. Here, we report that a novel member of the Trithorax family has a role unrelated to chromatin. It is encoded from an internal promoter in the ATX1 locus as an isoform containing only the SET domain (soloSET). It is located exclusively in the cytoplasm and its substrate is the elongation factor 1A (EF1A). Loss of SET, but not of the histone modifying ATX1-SET activity, affects cytoskeletal actin bundling illustrating that the two isoforms have distinct functions in Arabidopsis cells
Transient and asymmetric dust structures in the TeV-bright nova RS Oph revealed by spectropolarimetry
A long-standing question related to nova eruptions is how these eruptions can
lead to the formation of dust despite the ostensibly inhospitable environment
for dust within the hot, irradiated ejecta. Novae in systems such as the
symbiotic binary RS Oph offers a articularly clear view of some nova shocks and
any associated dust production. Here we use spectropolarimetric monitoring of
the RS Oph starting two days after its eruption in 2021 Aug. to show that: dust
was present in the RS Oph system as early as two days into the 2021 eruption;
the spatial distribution of this early dust was asymmetric, with components
both aligned with and perpendicular to the orbital plane of the binary; between
two and nine days after the start of the eruption, this early dust was
gradually destroyed; and dust was again created, aligned roughly with the
orbital plane of the binary, more than 80 days after the start of the outburst,
most likely as a result of shocks that arose as the ejecta interacted with
circumbinary material concentrated in the orbital plane. Modelling of X-rays
and very-high energy GeV and TeV emission from RS Oph days to months into the
2021 eruption suggests that collisions between the ejecta and the circumbinary
material may have led to shock formation in two regions: the polar -
perpendicular to the orbital plane where collimated outflows have been observed
after prior eruptions, and a circumbinary torus in the orbital plane. The
observations described here indicate that dust formed in approximately the same
two regions, supporting the connection between shocks and dust in novae and
revealing a very early onset of asymmetry. The spectropolarimetric signatures
of RS Oph in the first week into the 2021 outburst indicate: polarized flux
across the H{\alpha} emission line and position angle orientation relative to
the radio axis are similar to the spectropolarimetric signatures of AGNs.Comment: 9 pages, 10 figures, 1 table, resubmitted to the Astronomy &
Astrophysics after the first reviewer's repor
A cytoplasm-specific activity encoded by the Trithorax-like ATX1 gene
Eukaryotes produce multiple products from a single gene locus by alternative splicing, translation or promoter usage as mechanisms expanding the complexity of their proteome. Trithorax proteins, including the Arabidopsis Trithorax-like protein ATX1, are histone modifiers regulating gene activity. Here, we report that a novel member of the Trithorax family has a role unrelated to chromatin. It is encoded from an internal promoter in the ATX1 locus as an isoform containing only the SET domain (soloSET). It is located exclusively in the cytoplasm and its substrate is the elongation factor 1A (EF1A). Loss of SET, but not of the histone modifying ATX1-SET activity, affects cytoskeletal actin bundling illustrating that the two isoforms have distinct functions in Arabidopsis cells
The antimicrobial activity of magnetron sputtered Ag doped aluminum oxide coatings in vitro
The effect of Ag-doped aluminium oxide coatings deposited by magnetron sputtering method on the antibacterial efficiency against Gram-positive, Gram-negative bacteria and fungi has been investigated. The structure and composition of coatings were analysed by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), photoelectron spectroscopy (XPS) methods. The results of the study suggest that Ag-doped aluminium oxide coatings demonstrate improved bactericidal effect and have great potential in various medical applications.Досліджено вплив покриттів оксиду алюмінію зі сріблом, нанесених методом магнетронного напилення на антибактеріальну ефективність проти грампозитивних, грамнегативних бактерій та грибків. Структура та склад покриттів були проаналізовані за допомогою скануючої електронної мікроскопії (SEM), енергодисперсійної рентгенівської спектроскопії (EDS), методів фотоелектронної спектроскопії (XPS). Результати дослідження дозволяють стверджувати, що покриття оксиду алюмінію зі сріблом демонструють поліпшений бактерицидний ефект і мають великий потенціал використання в різних галузях медицини.Исследовано влияние покрытий оксида алюминия с серебром, нанесенных методом магнетронного напыления на антибактериальную эффективность против грамположительных, грамотрицательных бактерий и грибков. Структура и состав покрытий были проанализированы с помощью сканирующей электронной микроскопии (SEM), энергодисперсионной рентгеновской спектроскопии (EDS), методов фотоэлектронной спектроскопии (XPS). Результаты исследования позволяют утверждать, что покрытия оксида алюминия с серебром демонстрируют улучшенный бактерицидный эффект и имеют большой потенциал применения в различных областях медицины
Reforming sanitary-epidemiological service in Central and Eastern Europe and the former Soviet Union: an exploratory study
<p>Abstract</p> <p>Background</p> <p>Public health services in the Soviet Union and its satellite states in Central and Eastern Europe were delivered through centrally planned and managed networks of sanitary-epidemiological (san-epid) facilities. Many countries sought to reform this service following the political transition in the 1990s. In this paper we describe the major themes within these reforms.</p> <p>Methods</p> <p>A review of literature was conducted. A conceptual framework was developed to guide the review, which focused on the two traditional core public health functions of the san-epid system: communicable disease surveillance, prevention and control and environmental health. The review included twenty-two former communist countries in the former Soviet Union (fSU) and in Central and Eastern Europe (CEE).</p> <p>Results</p> <p>The countries studied fall into two broad groups. Reforms were more extensive in the CEE countries than in the fSU. The CEE countries have moved away from the former centrally managed san-epid system, adopting a variety of models of decentralization. The reformed systems remain mainly funded centrally level, but in some countries there are contributions by local government. In almost all countries, epidemiological surveillance and environmental monitoring remained together under a single organizational umbrella but in a few responsibilities for environmental health have been divided among different ministries.</p> <p>Conclusions</p> <p>Progress in reform of public health services has varied considerably. There is considerable scope to learn from the differing experiences but also a need for rigorous evaluation of how public health functions are provided.</p
An RNA Polymerase III-Dependent Heterochromatin Barrier at Fission Yeast Centromere 1
Heterochromatin formation involves the nucleation and spreading of structural and epigenetic features along the chromatin fiber. Chromatin barriers and associated proteins counteract the spreading of heterochromatin, thereby restricting it to specific regions of the genome. We have performed gene expression studies and chromatin immunoprecipitation on strains in which native centromere sequences have been mutated to study the mechanism by which a tRNAAlanine gene barrier (cen1 tDNAAla) blocks the spread of pericentromeric heterochromatin at the centromere of chromosome 1 (cen1) in the fission yeast, Schizosaccharomyces pombe. Within the centromere, barrier activity is a general property of tDNAs and, unlike previously characterized barriers, requires the association of both transcription factor IIIC and RNA Polymerase III. Although the cen1 tDNAAla gene is actively transcribed, barrier activity is independent of transcriptional orientation. These findings provide experimental evidence for the involvement of a fully assembled RNA polymerase III transcription complex in defining independent structural and functional domains at a eukaryotic centromere
Molecular mechanism of the priming by jasmonic acid of specific dehydration stress response genes in Arabidopsis
Happiness as alchemy: Positive mood leads to self-serving responses to social comparisons
- …