6,451 research outputs found
The Future of Canadian Climate Policy — with Marc Lee
No full textMarc Lee is a Senior Economist at the Canadian Centre for Policy Alternatives\u27 BC Office. In addition to tracking federal and provincial budgets and economic trends, Marc has published on a range of topics from poverty and inequality to globalization and international trade to public services and regulation. Marc is the Co-Director of the Climate Justice Project, a research partnership with UBC\u27s School of Community and Regional Planning that examines the links between climate change policies and social justice.Resources:Climate Justice Project: www.policyalternatives.ca/projects/cli…tice-projectMarc Lee\u27s Posts on Policy Note: www.policynote.ca/author/marclee/Canadian Centre for Policy Alternatives: www.policyalternatives.ca/Marc\u27s Twitter: twitter.com/MarcLeeCCPA International Panel on Climate Change, 2021 report: www.ipcc.ch/report/ar6/wg1
Climate Justice & Inequality: The Future of Canadian Climate Policy — with Marc Lee
No full textMarc Lee is a Senior Economist at the Canadian Centre for Policy Alternatives\u27 BC Office. In addition to tracking federal and provincial budgets and economic trends, Marc has published on a range of topics from poverty and inequality to globalization and international trade to public services and regulation. Marc is the Co-Director of the Climate Justice Project, a research partnership with UBC\u27s School of Community and Regional Planning that examines the links between climate change policies and social justice.Resources: Climate Justice Project: https://www.policyalternatives.ca/projects/climate-justice-projectMarc Lee\u27s Posts on Policy Note: https://www.policynote.ca/author/marclee/Canadian Centre for Policy Alternatives: https://www.policyalternatives.ca/Marc\u27s Twitter: https://twitter.com/MarcLeeCCPA International Panel on Climate Change, 2021 report: https://www.ipcc.ch/report/ar6/wg1
A Simple Fluorescence Microplate Assay to Monitor RNA-DNA Hybrid Unwinding by the Bacterial Transcription Termination Factor Rho
No full textInternational audienceTranscription termination factor Rho contributes to shape the transcriptomes of many bacteria and is essential in a large subset of them. Although the transcription termination function of Rho is not always easy to reconstitute and to study in vitro, assays based on the ATPdependent RNA-DNA hybrid unwinding activity of the factor can prove useful to dissect Rho mechanisms or to seek new antibiotics targeting Rho. However, current in vitro assays of Rho helicase activity are time-consuming, as they usually require radiolabeling of the hybrid substrates and analysis of reaction products by gel electrophoresis. Here, we describe a fluorescence-based microplate assay that informs on Rho helicase activity in a matter of minutes and allows the multiplexed analysis of conditions required for primary biochemical characterization or for drug screening
UKMARC AMC: Draft Rev 4.0: UK MARC format for archives and manuscripts control (UK MARC AMC)
No full textThis draft is the first attempt to establish a UK MARC specifically for Archives and Manuscripts Control since the British Library indicated that it would countenance such extensions to the national UK MARC format. In order to keep consistency with the general UK MARC format, standard UK MARC subject fields are not included in this document, since they should be taken from the latest version of the UK MARC manual. {A note of them should perhaps be included in UK MARC AMC.} {NB Text in braces is intended to be explanatory material for readers of this draft}. Certain other fields have not been included that might occasionally be used in the cataloguing of archival materials but would generally only be used for such materials in organizations which were combining archive
databases with library databases. This MARC version is intended for use with descriptions of archive or anuscript material that follow, or fit, the traditional style of cataloguing: we assume that these will normally relate
to paper or parchment originals. It is not intended for use with descriptions of other kinds of material. For these, fields may be drawn from the appropriate UK MARC document. MARC versions for use with archives in special formats should be developed, in order to complete the full range of facilities available to archivists and curators
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)
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
Friends of the Greenwood Library Presents Marc Leepson
No full textOn Tuesday, September 11, 2012 the Friends of the Janet D. Greenwood Library hosted its fall event, which featured an evening with Marc Leepson. Leepson is a journalist, historian and the author of seven books, including Lafayette: Lessons in Leadership from the Idealist General (Palgrave/Macmillan, 2011), a concise biography of the famed Marquis de Lafayette
Happy birthday:25 years of DEAD-box proteins
No full textRNA helicases of the DEAD-box family are found in all eukaryotes, most bacteria and many archaea. They play important roles in rearranging RNA-RNA and RNA-protein interactions. DEAD-box proteins are ATP-dependent RNA binding proteins and RNA-dependent ATPases. The first helicases of this large family of proteins were described in the 1980s. Since then our perception of these proteins has dramatically changed. From bona fide helicases, they became RNA binding proteins that separate duplex RNAs, in a local manner, by binding and bending the target RNA. In the present review we describe some of the experiments that were important milestones in the life of DEAD-box proteins since their birth 25 years ago.</p
Towards the design of synthetic riboregulators modulating the activity of transcription termination factor Rho
No full textLa biologie synthétique est une discipline qui a pour but de concevoir des objets et des systèmes biologiques nouveaux ou de reprogrammer des systèmes biologiques naturels pour leur faire effectuer une tâche précise. Un défi majeur en biologie synthétique est d'assurer un contrôle rigoureux de l'expression de gènes et des flux métaboliques dans les cellules dédiées à la bio-production ou la thérapie. Bien que des switches inductibles régulant généralement la transcription ou la traduction aient déjà été développés, leur utilité pratique est limitée par une faible diversité d'inducteurs / stimuli adaptés et par des gammes dynamiques souvent sous-optimales. Il devient de plus en plus clair qu'un contrôle optimal exigera la mise en place de réseaux de régulation complexes imitant les réseaux multicouches existant dans la nature. Afin d’élargir le panel de composants moléculaires permettant un tel contrôle, l’objectif de cette thèse était de concevoir un riboswitch synthétique capable de contrôler la terminaison de la transcription Rho-dépendante et potentiellement « adossable » à d’autres types de riborégulateurs. Rho est un facteur protéique bactérien ATP-dépendant qui induit la terminaison de la transcription pour de nombreux gènes. J’ai développé un prototype de riboswitch Rho-dépendant en modifiant un riborégulateur naturel présent dans la partie 5’ non traduite de l’opéron pgaABCD d’E coli avec un aptamère reconnaissant la théophylline. En parallèle, j’ai caractérisé différents facteurs Rho phylodivergents dans l’espoir que certains présentent une sensibilité accentuée à la structuration de l’ARN, une propriété qui pourrait éventuellement être utilisée pour augmenter la réponse d’un riboswitch synthétique Rho-dépendant. Enfin, j’ai développé un essai fluorescent de l’activité hélicase du facteur Rho permettant un débit de caractérisation élevé en microplaques. Mes résultats renforcent notre compréhension des mécanismes de la terminaison Rho-dépendante, offrent un premier exemple de riboswitch synthétique reposant sur ce mécanisme et ouvrent des perspectives intéressantes pour un meilleur contrôle des circuits synthétiques de régulation génique.The aim of synthetic biology is to design new biological objects and systems or to reprogram natural biological systems to perform a specific task. A major challenge in synthetic biology is to ensure the rigorous control of gene expression and metabolic fluxes in cells dedicated to bioproduction or therapy. Although regulatory switches acting at the transcriptional or translational level have been developed, their practical utility is limited by a low diversity of suitable inducers/stimuli and by suboptimal dynamic ranges. It is becoming increasingly clear that optimal control will require the development of complex regulatory circuits that mimic the multi-layered circuits found in nature. In order to broaden the panel of molecular components allowing suchcontrol, this thesis aimed to develop a synthetic riboswitch able to govern Rho-dependent transcription termination and to potentially complement other types of ribregulators. Rho is an ATP-dependent motor protein that disrupts transcription complexes throughout bacterial genomes. I have developed a prototype of Rho-dependent riboswitch by integrating a theophylline aptamer into a natural riboregulator present in the 5' leaderof the E coli pgaABCD operon. In parallel, I have characterised phylodivergent Rho factors in search of specimen(s) with increased sensitivity to RNA structure, a feature that could prove advantageous to increase the dynamic response of synthetic Rho-dependent riboswitches. Finally, I have developed a fluorescent assay to monitor the helicase activity of the Rho factor, there by allowing a high analytical throughput with a microplatereader. Altogether, this work sheds new light on the mechanisms of Rho-dependent termination, provides the first example of a synthetic Rho-dependent riboswitch, and opens interesting possibilities for the fine-tuning of complex regulatory circuits
Mechanisms and regulation of an essential RNA helicase in E. coli : the bacterial transcription termination factor Rho
No full textChez E. coli, Rho est un facteur essentiel qui contrôle l’expression de multiples unités transcriptionnelles via le phénomène de terminaison de la transcription. Rho est un moteur moléculaire ATP-dépendant ayant une activité ARN hélicase caractéristique de sa capacité à dissocier des obstacles (comme l’ARN polymérase) lors de sa translocation le long de sa piste ARN. Il existe différentes structures de Rho en interaction avec l’ARN qui suggèrent des mécanismes de translocation contradictoires. Afin de mieux comprendre ces mécanismes, nous avons utilisé deux approches complémentaires pour identifier les fonctionnalités moléculaires importantes au sein de l’ARN et de Rho : l’approche NAIM (Nucleotide Analog Interference Mapping) développée au laboratoire et la mutagenèse dirigée. Nos résultats excluent une organisation de l’anneau hexamérique en «trimère de dimère» (ainsi que les mécanismes de translocation qui en découlent) mais sont compatibles avec différents aspects rencontrés dans une structure en anneau asymétrique plus récente. Toutefois, nos résultats ne supportent pas le mécanisme d’escorte nucléotide par nucléotide qui découle de cette structure asymétrique. Ainsi, nous montrons que Rho contacte la chaîne ARN de façon hétérogène et ne nécessite un groupement 2’-OH que tous les sept nucléotides en moyenne. Par ailleurs, nous avons exploré l’interactome d’E. coli dans le but d’identifier d’éventuels régulateurs de la fonction de Rho. Nous montrons que la protéine hexamèrique Hfq présente une similitude topologique avec les protéines endogènes NusG et YaeO et que, comme elles, Hfq s’associe à Rho pour en réguler la fonction. L’interaction Hfq:Rho inhibe les activités enzymatiques de Rho. Ces résultats révèlent un nouveau mécanisme d’anti-terminaison de la transcription avec diverses implications possibles dans le métabolisme bactérien et/ou la virulence de germes pathogènes.In E. coli, Rho is an essential factor that controls the expression of multiple transcriptional units via the phenomenon of transcription termination. Rho is an ATP-dependent molecular motor displaying RNA helicase activity, a feature typical of Rho’s ability to dissociate obstacles (such as RNA polymerase) during translocation along its RNA track. Different structures of the Rho-RNA complex have been published and suggest contradictory mechanisms of translocation. In order to understand these mechanisms, we have used two complementary approaches to identify functionality molecular comports in RNA and Rho : the NAIM (Nucleotide Analog Interference Mapping) approach developed in the laboratory and site-directed mutagenesis. Our results exclude that Rho forms a functional "trimer of dimer" ring (which rules out related translocation mechanisms) but are compatible with various aspects encountered in a recent asymmetric ring structure. However, our results do not support the "nucleotide by nucleotide" escort mechanism inferred from this asymmetric structure. Indeed, we show that Rho forms heterogonous contacts with the RNA chain and only requires a 2'-OH every seven nucleotides on average. Furthermore, we explored the interactome of E. coli in order to identify potential regulators of Rho function. We show that the hexameric protein Hfq displays topological similarity with the endogenous proteins NusG and YaeO and, that, like them, Hfq associates with Rho to regulate Rho function. The Hfq:Rho interaction inhibits the enzymatic activities of Rho. These results reveal a novel mechanism of transcription anti-termination with potentially important implications in bacterial metabolism and/or virulence of pathogens
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