Structure-function analysis of the Pch2 ATPase and its implication in the meiotic recombination checkpoint

Tesis por compendio de publicaciones[ES]Durante la meiosis existe un mecanismo de vigilancia denominado checkpoint de recombinación meiótica que asegura la correcta segregación del material genético a los gametos, siendo de vital importancia para el mantenimiento de la integridad genómica en los organismos con reproducción sexual. Por ello, nos propusimos como objetivo profundizar en el papel de Pch2, una ATPasa específica de meiosis de la familia AAA+, en el checkpoint de recombinación meiótica de Saccharomyces cerevisiae. En esta tesis hemos determinado que el papel principal de Pch2 en el checkpoint inducido por defectos en la sinapsis es promover la fosforilación de Hop1 en T318 y su incorporación en los cromosomas. También hemos estudiado la relevancia funcional de diversos motivos de la proteína Pch2, como el sitio catalítico (actividad ATPasa) y el dominio N-terminal, analizando su efecto en el checkpoint así como en la localización de Pch2. Por otro lado, hemos contribuido al conocimiento de los factores que determinan la correcta localización de Pch2 en levaduras. Así, hemos desvelado que, junto a la metilación de la histona H3K79, la acetilación de la histona H4K16 también regula el mecanismo del checkpoint meiótico de S. cerevisiae, presumiblemente controlando la localización de Pch2. Además, hemos analizado la interacción Orc1-Pch2 en el DNA ribosómico (rDNA), concluyendo que, en contra de hipótesis previas, la localización de Pch2 en el nucleolo no es necesaria para el checkpoint. De hecho, nuestros últimos resultados indican que una población citoplásmica de Pch2 es capaz de llevar a cabo la función en el checkpoint. Por último, hemos expandido nuestra investigación a otro sistema modelo, como Caenorhabditis elegans, estudiando el papel de H3K79me en la meiosis de este nematodo, analizando su implicación en el checkpoint, y explorando su efecto sobre PCH-2. En conclusión, la ATPasa conservada evolutivamente Pch2 desempeña un papel fundamental en el checkpoint meiótico inducido por fallos en sinapsis, y el control de su localización subcelular es importante para ello, la cual viene determinada por diversos factores entre los que se incluyen determinadas modificaciones post-traduccionales de histonas.[EN]During meiosis there is a surveillance mechanism, the meiotic recombination checkpoint, which monitors the correct distribution of genetic material to gametes, being crucial for the maintenance of genomic integrity in sexually reproducing organisms. We aimed to further explore the role of Pch2, a meiosis-specific AAA+ ATPase, in the meiotic recombination checkpoint of Saccharomyces cerevisiae. In this thesis, we have determined that the critical role of Pch2 in the checkpoint induced by synapsis defects is to promote Hop1 phosphorylation at T318 and Hop1 association to unsynapsed meiotic chromosomes. We have also studied the functional relevance of critical residues of the Pch2 protein, such as the catalytic site (ATPase activity) and the N-terminal domain, by analyzing its impact on Pch2 localization and checkpoint function. On the other hand, we have contributed to discover several factors that determine Pch2 proper localization in yeast. Thus, we have revealed that, together with H3K79 methylation, proper levels of H4K16 acetylation regulate the meiotic recombination checkpoint, likely by controlling Pch2 distribution. Moreover, we have analyzed Orc1-Pch2 interaction at the ribosomal DNA (rDNA), concluding that, in contrast to previous hypotheses, Pch2 nucleolar localization is not required for the meiotic checkpoint. Indeed, we provide evidence indicating that a cytoplasmic pool of Pch2 sustains checkpoint function. Finally, we have expanded our investigation to another model system such as Caenorhabditis elegans. We have studied the meiotic role of H3K79 methylation in this nematode, analyzing its checkpoint implication and exploring its impact on PCH-2 regulation. In conclusion, the evolutionarily conserved Pch2 ATPase plays a critical role in the meiotic checkpoint induced by synapsis defects. The control of Pch2 subcellular localization orchestrated by several factors, including histone post-translational modifications, is vital for its checkpoint function

Avances metodológicos para la determinación de componentes de la miel mediante cromatografía de gases-espectometría de masas

Tesis doctoral inédita de la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de lectura:14-11-200

Implicación de los astrocitos hipotalámicos en las alteraciones metabólicas y en los cambios de composición corporal inducidos por malnutrición en los periodos neonatal y adulto: nuevas acciones de la leptina y la ghrelina

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Medicina, Departamento de Pediatría. Fecha de lectura: 15 de Diciembre de 201

Translation universals in the oral production of bilingual children

Producción CientíficaThis paper investigates two of the most widely analyzed universals in translation research, namely simplification and explicitation. We examine the oral production of bilingual children with different language pairs as available in the CHILDES project (MacWhinney 2000) (i.e. the FerFuLice, Ticio, Deuchar, Vila, Genesee and Pérez-Bazán corpora) as well as in other compilation forms (i.e. Ronjat 1913; Leopold 1939-1949; Swain 1972; Lanza 1988, 1997, 2001; and Cossato 2008). We address two main issues: whether instances of simplification and explicitation appear in the production of non-instructed interpreters and, if so, how their occurrence relates to the type of data (i.e. spontaneous or experimental) and the language pair involved. The results show that children acquiring two first languages often translate and use simplification and explicitation at varying degrees irrespective of the language pair. We conclude that the analysis of acquisition data can contribute to shed light on the nature of these translation universals.Junta de Castilla y León - Consejería de Educación (VA046A06; UV 30/02)Ministerio de Ciencia e Innovación - FEDER (BFF2002-00442)Ministerio de Educación y Ciencia (HUM2007-62213/FILO

The acquisition of Spanish and English as two first languages through the analysis of natural interpreting in bilingual children

Producción CientíficaResearch on the acquisition of two first languages from birth (2L1A) has focused, among other issues, on how the grammars of the two languages being acquired interact (e.g. Bhatia & Ritchie, 2012 ; De Houwer, 2009 ; Deuchar & Quay, 2000 ; Döpke, 2000 ; Köppe & Meisel, 1995 ). A case in point is natural interpreting which evidences how bilingual children exposed to two languages from birth deal with the grammatical properties of the two languages and how this leads them to potentially convey the same message in either (or both) of these languages. More specifically, as part of the simultaneous processing of their two L1s, 2L1 bilingual children have been reported to often translate between their two L1s ( Álvarez de la Fuente & Fernández Fuertes, 2012 , 2015 ; Cossato, 2008 ; Harris, 1980a , 1980b ; Harris & Sherwood, 1978 ), a phenomenon that has been called natural interpreting ( Harris, 1977 , 2003). In this respect, natural interpreting can be included with other language contact phenomena, such as interlinguistic influence or code-switching, as a typical defining property of 2L1A. Therefore, in this study we aim to offer an analysis of the way in which Spanish-English bilingual children use natural interpreting in their 2L1A process by focusing on the Spanish-English bilingual corpora freely available through the CHILDES project ( MacWhinney, 2000 ).Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA046A06; UV 30/02)Ministerio de Ciencia y Tecnología- FEDER (BFF2002-00442)Ministerio de Educación, Cultura y Deporte (HUM2007-62213/FILO

Análisis lingüístico de la traducción natural: datos de producción de dos niños gemelos bilingües inglés/español

La traducción natural es aquella realizada por bilingües en circunstancias cotidianas y sin haber recibido una formación en traducción (Harris 1977). Este trabajo se centra en las traducciones naturales orales encontradas en los datos de producción lingüística de dos niños bilingües simultáneos inglés/español (1;11-6;3 años). Incluyendo datos espontáneos y experimentales, la selección de los casos proceden de un estudio longitudinal (Fernández Fuertes et al. 2002-2005) y el análisis se basa en la propuesta de una serie de variables que recogen el comportamiento traductor de estos niños desde una perspectiva lingüística y contextual. El análisis demuestra que utilizan estrategias comunicativas para traducir cuando así se requiere y que mantienen una relación semántico-conceptual entre el texto origen y el texto meta, poniendo de manifiesto que este tipo de traducción es un fenómeno típico de la adquisición bilingüe que hay que tener en cuenta para describir cómo interactúan las competencia bilingüe y la traductora.Departamento de Filología Ingles

Linguistic theory and bilingual systems: Simultaneous and sequential English/Spanish bilingualism

Producción CientíficaUsing data from simultaneous and sequential bilingualism, we address a series of learnability issues by investigating the acquisition of four different structures: (i) the [Gender] feature of the Spanish Determiner in the production of English/ Spanish mixed Determiner Phrases; (ii) the [Determiner] feature of Tense in the production of null/overt subjects; (iii) the morphosyntactic status of definite articles and clitics; and (iv) the morphosyntactic characteristics of Spanish deverbal compounds. We compare spontaneous and experimental data elicited from children and adults in order to show how these linguistic constructs can account for the differences and similarities between native and non-native bilingual systems. The data reveal clear-cut differences between native and non-native production/ interpretation. We attribute this to feature specification and the way in which both groups access the input.Ministerio de Ciencia y Tecnología de España - FEDER (BFF2002-00442)Faculty of Arts of the University of Ottawa - Social Sciences and Humanities Research Council of Canada (410-2004-2034

Bilingual children as interpreters in everyday life: how natural interpreting reinforces minority languages

Producción CientíficaThis study analyses different contextual and linguistic variables that define the natural interpreting instances produced in spontaneous interactions by 19 young bilingual children (average age: 3;7) with different language pairs. In particular, we aim at characterizing the bilingual practice used by these children and (i) involve the consecutive use of their two languages and (ii) are shaped by the communicative strategies used by parents at home. The analysis is based on freely available corpora in CHILDES (MacWhinney 2000) (i.e. FerFuLice, Pérez-Bazán, Ticio, Vila, Deuchar; GNP) and diary annotations (i.e. Ronjat 1913; Leopold 1935-1945; Lanza 1988, 1997, 2001) that comprise the spontaneous and longitudinal production of these children. Our results show that the language strategies followed by parents at home in combination with the linguistic communities where they live play a key role on this bilingual practice.2020-04-042020-04-04Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA046A06)Junta de Castilla y León y FEDER (programa de apoyo a proyectos de investigación - Ref.VA009P17Ministerio de Ciencia y Tecnología y FEDER (BFF2002-00442)Ministerio de Educación, Cultura y Deporte (HUM2007-62213/FILO

The impact of ownership structure on corporate reputation: evidence from Spain

Research Question/Issue: This study examines the influence of firms' ownership structure on corporate reputation. Research Findings/ Insights: Using archival data from a panel of firms in Spain for 2000–2007, we found that ownership concentration in the hands of the largest shareholder erodes corporate reputation, whereas contestability of the main shareholder's power enhances it. Insider ownership shows a non-linear relationship with corporate reputation, with lower corporate reputation at low and very high levels of insider ownership. Finally, if the largest shareholder is either a pressure-resistant or a pressure-sensitive institutional investor, as opposed to other types of largest shareholder, corporate reputation is lower. This last finding markedly differentiates our sample of firms in Spain, a civil law country, from firms in common law countries such as the USA and the UK, where studies have found a positive relationship between institutional investors and corporate reputation. Theoretical/Academic Implications: Drawing on signaling and agency theories, our paper is, to the best of our knowledge, the first to analyze the influence of ownership structure on corporate reputation in civil law countries. Practitioners/Policy Implications: This study suggests that managers and directors should recognize how each characteristic of ownership structure influences the expectations of stakeholders. Low levels of ownership concentration in the hands of the largest shareholders, low differences in ownership concentration between first and second largest shareholders, and moderate levels of insider ownership are positive signals that should be communicated to foster corporate reputation. High levels of ownership concentration in the hands of the largest shareholders or high differences in ownership concentration between first and second largest shareholders impair corporate reputation and should be compensated by introducing corporate governance mechanisms that favor corporate reputation, such as increasing the number of independent directors or avoiding CEO duality

Hate Speech, Emotions, and Gender Identities : A Study of Social Narratives on Twitter with Trainee Teachers

The objective of this study is, on the one hand, to analyse emotional responses to the construction of hate speech relating to gender identity on Twitter. On the other hand, the objective is to evaluate the capabilities of trainee primary education teachers at constructing alternative counter-narratives to this socially alive issue, surrounding the approval of the Ley de Identidad de Género [Gender Identity Law] in Chile, in 2018. With this two-fold objective in mind, quantitative, descriptive, and inferential analysis and qualitative analysis techniques are all applied. The results inform us of the influence of socially constructed emotions and feelings that are expressed in social narratives. However, the narratives of the participants neither appeared to reach satisfactory levels of reflection on the social issues that stirred their own emotional responses, nor on the conflict between reason and the value judgements that they expressed in the digital debate (counter-narratives). These results point to the need to consider both emotions and feelings, as categories of social analysis, and to reflect on their forms of expression within the framework of education for inclusive democratic citizenship