2,480 research outputs found
The ?-subunit of the heterotrimeric G-protein affects jasmonate responses in Arabidopsis thaliana
No full textHeterotrimeric G-proteins have been implicated in having a role in many plant signalling pathways. To understand further the role of G-proteins, a preliminary experiment was performed to assess the impact of the G? subunit loss-of-function mutation gpa1-1 on the Arabidopsis transcriptome. The analysis indicated that the G? subunit may play a role in response to jasmonic acid (JA). Consistent with this, G? mutants showed a reduced response to JA in inhibition of chlorophyll accumulation and root growth, whilst G? gain-of-function plants overexpressing G? showed the opposite phenotype. The levels of JA and related compounds were unaffected in the gpa1-1 mutant, as was autoregulation of the Allene Oxide Synthase (AOS) gene that encodes a key enzyme for JA biosynthesis. In contrast, further analyses using G? loss- and gain-of-function Arabidopsis lines indicated that G? positively modulates the expression of the Vegetative Storage Protein (VSP) gene. This indicates that the G? subunit regulates a subset of JA-regulated genes defining a branch point in this signalling pathway in Arabidopsis. Further analysis of the impact of G? loss of function upon the JA-regulated transcriptome using Arabidopsis full genome arrays indicated that up to 29% of genes that are >2-fold regulated by JA in the wild type are misregulated in the G? mutant. This supports the observation that a significant proportion of, but not all, JA-regulated gene expression is mediated by G
MARC 21 para recursos contínuos
No full textTranslation and adaptation of the MARC 21 Format for Bibliographic Data, and MARC 21 Format for Holdings Data, Network Development and MARC Standards Office, Library of Congress, USA, by Angela Salles. Rio de Janeiro, 2010. 2 v. V.1 MARC 21 format for bibliographic data (updated until October 2010). V.2 MARC 21 format for data collection (Holdings) (updated until October 2008)
Abscisic acid induces CBF gene transcription and subsequent induction of cold-regulated genes via the CRT promoter element
No full textMany cold-regulated genes of Arabidopsis are inducible by abscisic acid (ABA) as well as by cold. This has been thought to occur via two separate signaling pathways, with ABA acting via ABA-responsive promoter elements and low temperature activating the C-repeat element (CRT; dehydration-responsive) promoter element via CBF (DREB1) transcription factors. We show here that ABA is also capable of activating the CRT promoter element. Although the more recently discovered ABA-inducible CBF4 transcription factor might have accounted for this, we show here that CBF1-3 transcript levels also increase in response to elevated ABA levels. This increase in CBF1-3 transcript levels appears to be at least in part due to increased activity of the CBF promoters in response to ABA. A total of 125 bp of the CBF2 promoter, which has previously been shown to be sufficient for cold-, mechanical-, and cycloheximide-induced expression, was also sufficient for ABA-induced expression. However, the ABA-responsive promoter element-like motif within this region is not needed for ABA-induced expression. An observed increase in CBF protein levels after ABA treatment, together with previous data showing that increased CBF levels are sufficient for cold-regulated gene induction, suggests that ABA-induced increases in CBF1-3 transcript levels do have the potential to activate the CRT. Our data indicate therefore that activation of the CRT may also occur via a novel ABA-inducible signaling pathway using the normally cold-inducible CBFs
MARC 21 para recursos contínuos.
No full textTradução e adaptação de MARC 21 Format for Bibliographic Data e MARC 21 Format for Holdings Data, da Network Development and MARC Standards Office, da Library of Congress, USA, por Angela Salles
Analysis of Readex's Serial Set MARC records: improving the data for the library catalog
No full textColorado State University Libraries (CSUL) purchased the digitized United States Congressional Serial Set, 1817-1994 and American State Papers (1789-1838) from the Readex Division of NewsBank, inc and, once funds and records were available, the accompanying MARC records. The breadth of information found in the Serial Set is described, along with the difficulties in using the print version (incorporated in the literature review, which includes citations of announcements of the digital collections and reviews of the software). The digital version of the Serial Set has its advantages, but there are additional rewards (much greater discovery opportunities) when items in the digital collection are directly accessible from the library catalog. The purchased MARC records, while overall excellent, had problems that needed to be corrected before they were loaded into CSUL's Innovative Interfaces library catalog. Patron access impact was used as a criterion when determining which of the records would be fixed before loading. High impact problems were identified and solutions derived for: multiple 245 (title) fields; 245 second indicator zero with titles beginning with a, an, or the; dollar sign used in text; fixed field date; languages; subject headings; creating proxy URLs; classification numbers; and author authority control (e.g. corporate entries and presidential entry errors)
The regulation and role of oxidative signal-inducible 1 protein kinase in Arabidopsis thaliana
No full textWord processed copy.Includes bibliographical references (leaves 209-232).This study attempted to further characterise OXI1 protein kinase. Confocal microscopy and subcellular fractionation studies revealed a cytosolic localisation pattern for OXI1. Employment of a bioinformatics approach confirmed the induction of OXI1 gene expression in response to a range of AOS generating stimuli. However, the transcriptional increase of OXI1 in response to salinity and heat appears to be of no biological significance since the oxi1 mutant did not display altered tolerance to these two stresses in comparison to wild type
J.C. Bach's London keyboard sonatas : style and context
No full textJ. C. Bach's keyboard works include several sets of accompanied sonatas, a genre that enjoyed a wide popularity during the Classical era, but never
found its way into the concert repertoire. The accompanied sonata was a genre meant for domestic performance; the solo keyboard sonata, on
the other hand, was adopted in due course by concert audiences. J. C. Bach composed works within both genres during most of his productive years, and his output constitutes a corpus of remarkable consistency. J. C. Bach's removal to London in 1762 coincided with his clear adoption of a galant style, marked by the Italianate influence, and the abandonment of most Baroque traits. The British milieu provided additional factors: the rise of the pianoforte, a thriving music-publishing market, and a great interest in domestic music making among the affluent classes. These factors marked J. C. Bach's output at various levels. Keyboard works had to conform to the proficiency of the amateur performer, a
fact reflected in the accompanied output mostly. The number of movements, their length, and the inclusion of particular technical devices are readily observable differences between the two genres. The most remarkable
distinction lies perhaps in the preference for binary sonata format in the accompanied. sonatas from the mid 1760s to the 1770s, in spite of a later tendency for tripartite designs in both genres. J. C. Bach's lifelong preference for motivic phrase structure conditioned his keyboard production and partly explains the gap in quality between some of his works and sonatas composed around the same time by Haydn and Mozart, who developed more effective means to connect the melodic material
to higher structural units. J. C. Bach's influence, however, endured in Mozart's handling of melody, and his keyboard production constitutes, in spite of some flaws, a noteworthy example of elegance and craftsmanship
Increased rate of degradation of c-myc mRNA in interferon-treated Daudi cells.
No full textInternational audienceThe recent observation made in our laboratory that cellular myc (c-myc) mRNA has a very short half-life in a variety of normal and transformed human cells emphasized the potential importance of post-transcriptional regulation of c-myc gene expression. Jonak and Knight [Jonak, G. J. & Knight, E., Jr. (1984) Proc. Natl. Acad. Sci. USA 81, 1747-1750] have reported a selective reduction of c-myc mRNA accumulation in lymphoblastoid Daudi cells treated with human beta interferon. This provided a suitable situation in which to examine a possible action of negative modulators of c-myc expression at the level of mRNA stability. Our results confirm the observation by Jonak and Knight that c-myc mRNA level is depressed in cells treated with beta interferon and extend it to alpha 2 interferon. Furthermore, we now demonstrate that interferon has no effect on c-myc transcription rate in isolated nuclei but rather reduces the half-life of its mRNA. Conversely, we show that it increases the level of HLA-A2 mRNA by stimulating its transcription
The potential role of nonpharmacologic electrophysiology-based interventions in improving outcomes in patients hospitalized for heart failure
No full textHospitalization for heart failure (HHF) is commonly associated with symptomatic improvement in response to standard medical therapy, yet there remains a substantial risk of rehospitalization and death. Clinically stable outpatients and decompensated inpatients represent two types of patients with chronic heart failure. In the former, treatment of common heart rhythm disorders with nonpharmacologic electrophysiology-based interventions is of substantial benefit in select patients. The potential benefits of these interventions in the hospitalized setting are not well studied. In this review, current knowledge is discussed and future research directions are suggested with nonpharmacologic electrophysiology-based interventions to reduce the morbidity and mortality associated with patients with HHF
Comparative experimental approach to investigate the thermal behaviour of vertical greened façades of buildings
No full textGreening the building envelope is not a new concept, however it has not been fully approved as an energy saving method for the built environment. Vertical green can provide a cooling potential on the building surface, as plants are functioning as a solar filter and prevent the adsorption of heat radiation of building materials extensively. In this study a comparative thermal analysis of vertical green attached to a façade element is presented. An experimental set up (stationary conditions) has been developed to measure the temperature gradient through a reference cavity wall, in order to quantify the contribution of vegetation to the thermal behaviour of the building envelope. The results show temperature differences between the bare wall and between the different vertical greening systems analysed, up to 1.7 °C for the direct greening system and 8.4 °C for the living wall system based on planter boxes after 8 h of heating for summer conditions, due to the different “material” layers involved. However, the insulation material of the bare wall moderates the prevailing temperature difference between the outside and inside climate chamber, resulting in no temperature difference for the interior climate chamber for summer conditions.Materials and Environmen
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