944 resultados para Chesterman, Andrew: Memes of translation


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Trypanosoma brucei and related pathogens transcribe most genes as polycistronic arrays that are subsequently processed into monocistronic mRNAs. Expression is frequently regulated post-transcriptionally by cis-acting elements in the untranslated regions (UTRs). GPEET and EP procyclins are the major surface proteins of procyclic (insect midgut) forms of T. brucei. Three regulatory elements common to the 3' UTRs of both mRNAs regulate mRNA turnover and translation. The glycerol-responsive element (GRE) is unique to the GPEET 3' UTR and regulates its expression independently from EP. A synthetic RNA encompassing the GRE showed robust sequence-specific interactions with cytoplasmic proteins in electromobility shift assays. This, combined with column chromatography, led to the identification of 3 Alba-domain proteins. RNAi against Alba3 caused a growth phenotype and reduced the levels of Alba1 and Alba2 proteins, indicative of interactions between family members. Tandem-affinity purification and co-immunoprecipitation verified these interactions and also identified Alba4 in sub-stoichiometric amounts. Alba proteins are cytoplasmic and are recruited to starvation granules together with poly(A) RNA. Concomitant depletion of all four Alba proteins by RNAi specifically reduced translation of a reporter transcript flanked by the GPEET 3' UTR. Pulldown of tagged Alba proteins confirmed interactions with poly(A) binding proteins, ribosomal protein P0 and, in the case of Alba3, the cap-binding protein eIF4E4. In addition, Alba2 and Alba3 partially cosediment with polyribosomes in sucrose gradients. Alba-domain proteins seem to have exhibited great functional plasticity in the course of evolution. First identified as DNA-binding proteins in Archaea, then in association with nuclear RNase MRP/P in yeast and mammalian cells, they were recently described as components of a translationally silent complex containing stage-regulated mRNAs in Plasmodium. Our results are also consistent with stage-specific regulation of translation in trypanosomes, but most likely in the context of initiation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A process that we refer to as control by epistasy of synthesis (CES process) occurs during chloroplast protein biogenesis in Chlamydomonas reinhardtii: the synthesis of some chloroplast-encoded subunits, the CES subunits, is strongly attenuated when some other subunits from the same complex, the dominant subunits, are missing. Herein we investigate the molecular basis of the CES process for the biogenesis of the cytochrome b6f complex and show that negative autoregulation of cytochrome f translation occurs in the absence of other complex subunits. This autoregulation is mediated by an interaction, either direct or indirect, between the 5′ untranslated region of petA mRNA, which encodes cytochrome f, and the C-terminal domain of the unassembled protein. This model for the regulation of cytochrome f translation explains both the decreased rate of cytochrome f synthesis in vivo in the absence of its assembly partners and its increase in synthesis when significant accumulation of the C-terminal domain of the protein is prevented. When expressed from a chimeric mRNA containing the atpA 5′ untranslated region, cytochrome f no longer showed an assembly-dependent regulation of translation. Conversely, the level of antibiotic resistance conferred by a chimeric petA-aadA-rbcL gene was shown to depend on the state of assembly of cytochrome b6f complexes and on the accumulation of the C-terminal domain of cytochrome f. We discuss the possible ubiquity of the CES process in organellar protein biogenesis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A critical step in the degradation of many eukaryotic mRNAs is a decapping reaction that exposes the transcript to 5′ to 3′ exonucleolytic degradation. The dual role of the cap structure as a target of mRNA degradation and as the site of assembly of translation initiation factors has led to the hypothesis that the rate of decapping would be specified by the status of the cap binding complex. This model makes the prediction that signals that promote mRNA decapping should also alter translation. To test this hypothesis, we examined the decapping triggered by premature termination codons to determine whether there is a down-regulation of translation when mRNAs were recognized as “nonsense containing.” We constructed an mRNA containing a premature stop codon in which we could measure the levels of both the mRNA and the polypeptide encoded upstream of the premature stop codon. Using this system, we analyzed the effects of premature stop codons on the levels of protein being produced per mRNA. In addition, by using alterations either in cis or in trans that inactivate different steps in the recognition and degradation of nonsense-containing mRNAs, we demonstrated that the recognition of a nonsense codon led to a decrease in the translational efficiency of the mRNA. These observations argue that the signal from a premature termination codon impinges on the translation machinery and suggest that decapping is a consequence of the change in translational status of the mRNA.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

By examining the front of virus invasion in immature pea embryos infected with pea seed-borne mosaic virus (PSbMV), the selective control of different host genes has been observed. From our observations, the early responses to PSbMV replication can be grouped into three classes, inhibited host gene expression, induced host gene expression, and no effect on a normal host function. The expression of two heat-inducible genes encoding HSP70 and polyubiquitin was induced coordinately with the onset of virus replication and the down-regulation of two other genes encoding lipoxygenase and heat shock cognate protein. The down-regulation was part of a general suppression of host gene expression that may be achieved through the degradation of host transcripts. We discuss the possibilities of whether the induction of HSP70 and polyubiquitin genes represents a requirement for the respective protein products by the virus or is merely a consequence of the depletion of other host transcripts. The former is feasible, as the induction of both genes does result in increased HSP70 and ubiquitin accumulation. This also indicates that, in contrast to some animal virus infections, there is not a general inhibition of translation of host mRNAs following PSbMV infection. This selective control of host gene expression was observed in all cell types of the embryo and identifies mechanisms of cellular disruption that could act as triggers for symptom expression.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The functioning of the neuronal dendrite results from a variety of biological processes including mRNA transport to and protein translation in the dendrite. The complexity of the mRNA population in dendrites suggests that specific biological processes are modulated through the regulation of dendritic biology. There are various classes of mRNAs in dendrites whose translation modulates the ability of the dendrite to receive and integrate presynaptic information. Among these mRNAs are those encoding selective transcription factors that function in the neuronal soma and ionotropic glutamate receptors that function on the neuronal membrane. Conclusive evidence that these mRNAs can be translated is reviewed, and identification of the endogenous sites of translation in living dendrites is presented. These data, as well as those described in the other articles resulting from this colloquium, highlight the complexity of dendritic molecular biology and the exquisitely selective and sensitive modulatory role played by the dendrite in facilitating intracellular and intercellular communication.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Multimeric protein complexes in chloroplasts and mitochondria are generally composed of products of both nuclear and organelle genes of the cell. A central problem of eukaryotic cell biology is to identify and understand the molecular mechanisms for integrating the production and accumulation of the products of the two separate genomes. Ribulose bisphosphate carboxylase (Rubisco) is localized in the chloroplasts of photosynthetic eukaryotic cells and is composed of small subunits (SS) and large subunits (LS) coded for by nuclear rbcS and chloroplast rbcL genes, respectively. Transgenic tobacco plants containing antisense rbcS DNA have reduced levels of rbcS mRNA, normal levels of rbcL mRNA, and coordinately reduced LS and SS proteins. Our previous experiments indicated that the rate of translation of rbcL mRNA might be reduced in some antisense plants; direct evidence is presented here. After a short-term pulse there is less labeled LS protein in the transgenic plants than in wild-type plants, indicating that LS accumulation is controlled in the mutants at the translational and/or posttranslational levels. Consistent with a primary restriction at translation, fewer rbcL mRNAs are associated with polysomes of normal size and more are free or are associated with only a few ribosomes in the antisense plants. Effects of the rbcS antisense mutation on mRNA and protein accumulation, as well as on the distribution of mRNAs on polysomes, appear to be minimal for other chloroplast and nuclear photosynthetic genes. Our results suggest that SS protein abundance specifically contributes to the regulation of LS protein accumulation at the level of rbcL translation initiation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The structure of m7GpppN (where N is any nucleotide), termed cap, is present at the 5' end of all eukaryotic cellular mRNAs (except organellar). The eukaryotic initiation factor 4E (eIF-4E) binds to the cap and facilitates the formation of translation initiation complexes. eIF-4E is implicated in control of cell growth, as its overexpression causes malignant transformation of rodent cells and deregulates HeLa cell growth. It was suggested that overexpression of eIF-4E results in the enhanced translation of poorly translated mRNAs that encode growth-promoting proteins. Indeed, enhanced expression of several proteins, including cyclin D1 and ornithine decarboxylase (ODC), was documented in eIF-4E-overexpressing NTH 3T3 cells. However, the mechanism underlying this increase has not been elucidated. Here, we studied the mode by which eIF-4E increases the expression of cyclin D1 and ODC. We show that the increase in the amount of cyclin D1 and ODC is directly proportional to the degree of eIF-4E overexpression. Two mechanisms, which are not mutually exclusive, are responsible for the increase. In eIF-4E-overexpressing cells the rate of translation initiation of ODC mRNA was increased inasmuch as the mRNA sedimented with heavier polysomes. For cyclin D1 mRNA, translation initiation was not increased, but rather its amount in the cytoplasm increased, without a significant increase in total mRNA. Whereas, in the parental NIH 3T3 cell line, a large proportion of the cyclin D1 mRNA was confined to the nucleus, in eIF-4E-overexpressing cells the vast majority of the mRNA was present in the cytoplasm. These results indicate that eIF-4E affects directly or indirectly mRNA nucleocytoplasmic transport, in addition to its role in translation initiation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article is the English version of “Terminología y traducción económica francés-español: evaluación de recursos terminológicos en el ámbito contable” by Daniel Gallego Hernández. It was not published on the print version of MonTI for reasons of space. The online version of MonTI does not suffer from these limitations, and this is our way of promoting plurilingualism.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The aim of this paper is to describe the use that professional translators make of corpora as translation resources. First, we briefly review the literature on translation practitioners’ use of corpora in the contexts of both translation training and professional translation. Then we present our survey-based study, analyse the uptake of corpora among Spanish translators and describe the use of this kind of translation resource. The results show that even if corpora are not as frequently used as other kinds of resources, such as dictionaries, there are professional translators who do use corpora, in a variety of ways, in their work. Additionally, non-users do not seem entirely sceptical about corpora. Against that backdrop, translator trainers are invited to continue to report on how corpora can be used as translation resources.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Metaphor has been widely discussed within the discipline of Translation Studies, predominantly with respect to translatability and transfer methods. It has been argued that metaphors can become a translation problem, since transferring them from one language and culture to another one may be hampered by linguistic and cultural differences. A number of translation procedures for dealing with this problem have been suggested, e.g., substitution (metaphor into different metaphor), paraphrase (metaphor into sense), or deletion. Such procedures have been commented on both in normative models of translation (how to translate metaphors) and in descriptive models (how metaphors have been dealt with in actual translations). After a short overview of how metaphor has been dealt with in the discipline of Translation Studies, this paper discusses some implications of a cognitive approach to metaphors for translation theory and practice. Illustrations from authentic source and target texts (English and German, political discourse) show how translators handled metaphorical expressions, and what effects this had for the text itself, for text reception by the addressees, and for subsequent discursive developments. © 2004 Elsevier B.V. All right reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In recent years, technologically advanced methodologies such as Translog have gained a lot of ground in translation process research. However, in this paper it will be argued that quantitative research methods can be supplemented by ethnographic qualitative ones so as to enhance our understanding of what underlies the translation process. Although translation studies scholars have sometimes applied an ethnographic approach to the study of translation, this paper offers a different perspective and considers the potential of ethnographic research methods for tapping cognitive and behavioural aspects of the translation process. A number of ethnographic principles are discussed and it is argued that process researchers aiming to understand translators’ perspectives and intentions, how these shape their behaviours, as well as how translators reflect on the situations they face and how they see themselves, would undoubtedly benefit from adopting an ethnographic framework for their studies on translation processes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Since the transfer of a message between two cultures very frequently takes place through the medium of a written text qua communicative event, it would seem useful to attempt to ascertain whether there is any kind of pattern in the use of strategies for the effective interlingual transfer of this message. Awareness of potentially successful strategies, within the constraints of context, text type, intended TL function and TL reader profile will enhance quality and cost-effectiveness (time, effort, financial costs) in the production of the target text. Through contrastive analysis of pairs of advertising texts, SL and TL, French and English, this study will attempt to identify the nature of some recurring choices made by different translators in the attempt to recreate ST information in the TL in such a manner as to reproduce as closely as possible the informative, persuasive and affective functions of the text as advertising material. Whilst recurrence may be seen to be significant in terms of illustrating tendencies with regard to the solution of problems of translation, this would not necessarily be taken as confirmation of the existence of pre-determined or prescriptive rules. These tendencies could, however, be taken as a guide to potential solutions to certain kinds of context-bound and text-type specific problem. Analysis of translated text-pairs taken from the field of advertising should produce examples of constraints posed by the need to select the content, tone and form of the Target Text, in order to ensure maximum efficacy of persuasive effect and to ensure the desired outcome, as determined by the Source Text function. When evaluating the success of a translated advertising text, constraints could be defined in terms of the culture-specific references or assumptions on which a Source Text may build in order to achieve its intended communicative function within the target community.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The present thesis is located within the framework of descriptive translation studies and critical discourse analysis. Modern translation studies have increasingly taken into account the complexities of power relations and ideological management involved in the production of translations. Paradoxically, persuasive political discourse has not been much touched upon, except for studies following functional (e.g. Schäffner 2002) or systemic-linguistic approaches (e.g. Calzada Pérez 2001). By taking 11 English translations of Hitler’s Mein Kampf as prime examples, the thesis aims to contribute to a better understanding of the translation of politically sensitive texts. Actors involved in political discourse are usually more concerned with the emotional appeal of their message than they are with its factual content. When such political discourse becomes the locus of translation, it may equally be crafted rhetorically, being used as a tool to persuade. It is thus the purpose of the thesis to describe subtle ‘persuasion strategies’ in institutionally translated political discourse. The subject of the analysis is an illustrative corpus of four full-text translations, two abridgements, and five extract translations of Mein Kampf. Methodologically, the thesis pursues a top-down approach. It begins by delineating sociocultural and situative-agentive conditions as causal factors impinging on the individual translations. Such interactive and interpersonal factors determined textual choices. The overall textual analysis consists of an interrelated corpus-driven and corpus-based approach. It demonstrates how corpus software can be fruitfully harnessed to discern ‘ideological significations’ in the translated texts. Altogether, the thesis investigates how translational decision-makers attempted to position the source text author and his narrative in line with overall rhetorical purposes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The present thesis examines Palestinian-Israeli peace initiatives as politically negotiated texts and their different Arabic, English and Hebrew language versions. Its aim is to make a contribution to a deeper understanding of the role of translation and recontextualization of politically negotiated texts in situations of ongoing contemporary conflict. In modern Translation Studies, although research exists on the translation of political texts following functional (e.g. Schäffner 2002) or systemic-linguistic (e.g. Calzada-Pérez 2001) approaches or applying narrative theory (Baker 2006), peace initiatives and politically negotiated texts are still a largely under-researched genre of political texts. The thesis – which takes 31 Arabic, English and Hebrew language versions of 5 different Palestinian-Israeli peace initiatives as its corpus – operates within the framework of product-oriented Descriptive Translation Studies (Lambert and Van Gorp 1985) and Critical Discourse Analysis (Fairclough 1992). For all of the peace initiatives analysed, there exist several language versions which were made available in different contexts by different institutions and for different readerships and purposes. The thesis pursues a top-down approach. It begins with presenting the socio-cultural and political contexts of the production of the original versions of the respective peace initiatives (the source texts) and their different language versions (target texts), focusing on their underlying functions and principles of audience design. It then moves to examine how the textual profiles of the language versions of peace initiatives reflect aspects of ideology, political affiliation and power relations at both the macro- and micro-structural levels. The final step is to account for these aspects in terms of socio-political and institutional conditions of the production of the translations. The overall textual analysis demonstrates that when translated, peace initiatives can be interpreted differently by different institutions in their attempt to promote their respective political interests and narratives. Also, it is very frequently that translations produced in one specific institutional context are recontextualised for use in another one. Such recontextualisation goes hand in hand with further textual amendments. To summarize, the thesis demonstrates how these translations – as products – are (re)framed and (re)contextualized in different institutional settings in order to serve different purposes. These texts, thus, play different roles in situations of ongoing contemporary conflict depending on the institutional context in which they are presented and the purposes they set to serve. These main findings make an original contribution to the discipline of Translation Studies in respect of emphasizing the need to study translations in their socio-political, historical and institutional contexts.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article explores the settings and practices of translation at three types of political institutions, i.e. national, supranational, and non-governmental organisations. The three institutions are the translation service of the German Foreign Office, the translation department of the European Central Bank, and translation provision by the non-governmental organisation Amnesty International. The three case studies describe the specific translation practices in place at these institutions and illustrate some characteristic translation strategies. In this way, we reflect on how different translation practices can impact on translation agency and how these practices in turn are influenced by the type of institution and its organisational structure. The article also aims to explore to which extent the characteristics of collectivity, anonymity and standardisation, and of institutional translation as self-translation are applicable to the institutions under discussion.