1,313 research outputs found
Telomere-driven diseases and telomere-targeting therapies
Telomeres, the protective ends of linear chromosomes, shorten throughout an individual's lifetime. Telomere shortening is proposed to be a primary molecular cause of aging. Short telomeres block the proliferative capacity of stem cells, affecting their potential to regenerate tissues, and trigger the development of age-associated diseases. Mutations in telomere maintenance genes are associated with pathologies referred to as telomere syndromes, including Hoyeraal-Hreidarsson syndrome, dyskeratosis congenita, pulmonary fibrosis, aplastic anemia, and liver fibrosis. Telomere shortening induces chromosomal instability that, in the absence of functional tumor suppressor genes, can contribute to tumorigenesis. In addition, mutations in telomere length maintenance genes and in shelterin components, the protein complex that protects telomeres, have been found to be associated with different types of cancer. These observations have encouraged the development of therapeutic strategies to treat and prevent telomere-associated diseases, namely aging-related diseases, including cancer. Here we review the molecular mechanisms underlying telomere-driven diseases and highlight recent advances in the preclinical development of telomere-targeted therapies using mouse models.Research in the Blasco laboratory is funded by the Spanish Ministry of Economy and Competitiveness and Fondo Europeo de Desarrollo Regional project RET OS (grant SAF2013-45111-R), the European Research Council project TEL STEM CELL (grant ERC-2008-AdG/232854), and Fondacion Botin.S
Mice with hyper-long telomeres show less metabolic aging and longer lifespans
Short telomeres trigger age-related pathologies and shorter lifespans in mice and humans. In the past, we generated mouse embryonic (ES) cells with longer telomeres than normal (hyper-long telomeres) in the absence of genetic manipulations, which contributed to all mouse tissues. To address whether hyper-long telomeres have deleterious effects, we generated mice in which 100% of their cells are derived from hyper-long telomere ES cells. We observe that these mice have longer telomeres and less DNA damage with aging. Hyper-long telomere mice are lean and show low cholesterol and LDL levels, as well as improved glucose and insulin tolerance. Hyper-long telomere mice also have less incidence of cancer and an increased longevity. These findings demonstrate that longer telomeres than normal in a given species are not deleterious but instead, show beneficial effects.S
Entrapped Transient Chloroform Solvates of Bilastine
The knowledge about the solid forms landscape of Bilastine (BL) has been extended. The crystal structures of two anhydrous forms have been determined, and the relative thermodynamic stability among the three known anhydrous polymorphs has been established. Moreover, three chloroform solvates with variable stoichiometry have been identified and characterized, showing that S3CHCl3-H2O and SCHCl3 can be classified as transient solvateswhich transforminto the newchloroform solvate SCHCl3-H2O when removed fromthemother liquor. The determination of their crystal structures from combined single crystal/synchrotron X-ray powder diffraction data has allowed the complete characterization of these solvates, being two of them heterosolvates (S3CHCl3-H2O and SCHCl3-H2O) and SCHCl3 a monosolvate. Moreover, the temperature dependent stability and interrelation pathways among the chloroform solvates and the anhydrous forms of BL have been studied
Telomeric RNAs are essential to maintain telomeres
Telomeres are transcribed generating long non-coding RNAs known as TERRA. Deciphering the role of TERRA has been one of the unsolved issues of telomere biology in the past decade. This has been, in part, due to lack of knowledge on the TERRA loci, thus preventing functional genetic studies. Here, we describe that long non-coding RNAs with TERRA features are transcribed from the human 20q and Xp subtelomeres. Deletion of the 20q locus by using the CRISPR-Cas9 technology causes a dramatic decrease in TERRA levels, while deletion of the Xp locus does not result in decreased TERRA levels. Strikingly, 20q-TERRA ablation leads to dramatic loss of telomere sequences and the induction of a massive DNA damage response. These findings identify chromosome 20q as a main TERRA locus in human cells and represent the first demonstration in any organism of the essential role of TERRA in the maintenance of telomeres.We are indebted to R. Torres and S. Rodriguez for advice in the CRISPR-Cas9 technology and helpful discussions. We thank D. Megías for the quantification of confocal imagesignals and to O. Dominguez for troubleshooting with cloning and sequencing. We thank S. Llanos for the p21 promoter reporter (described in ref. 33). Research in the Blasco lab is funded by the Spanish Ministry of Economy and Competitiveness Project (SAF2013-45111-R), the Madrid Regional Government Project S2010/BMD-2303 (ReCaRe),Fundacio´n Botı´n (Spain) and AXA Research Fund (AXA 2011, Spain).S
A genetic interaction between RAP1 and telomerase reveals an unanticipated role for RAP1 in telomere maintenance
RAP1 is one of the components of shelterin, the capping complex at chromosome ends or telomeres, although its role in telomere length maintenance and protection has remained elusive. RAP1 also binds subtelomeric repeats and along chromosome arms, where it regulates gene expression and has been shown to function in metabolism control. Telomerase is the enzyme that elongates telomeres, and its deficiency causes a premature aging in humans and mice. We describe an unanticipated genetic interaction between RAP1 and telomerase. While RAP1 deficiency alone does not impact on mouse survival, mice lacking both RAP1 and telomerase show a progressively decreased survival with increasing mouse generations compared to telomerase single mutants. Telomere shortening is more pronounced in Rap1-/- Terc-/- doubly deficient mice than in the single-mutant Terc-/- counterparts, leading to an earlier onset of telomere-induced DNA damage and degenerative pathologies. Telomerase deficiency abolishes obesity and liver steatohepatitis provoked by RAP1 deficiency. Using genomewide ChIP sequencing, we find that progressive telomere shortening owing to telomerase deficiency leads to re-localization of RAP1 from telomeres and subtelomeric regions to extratelomeric sites in a genomewide manner. These findings suggest that although in the presence of sufficient telomere reserve RAP1 is not a key factor for telomere maintenance and protection, it plays a crucial role in the context of telomerase deficiency, thus in agreement with its evolutionary conservation as a telomere component from yeast to humans.Research in the Blasco laboratory is funded by Spanish Ministry of Economy and Competitiveness (MINECO and FEDER) Project RETOS (SAF2013-45111-R), the European Research Council (ERC) Project TEL STEM CELL (ERC-2008-AdG/232854), and Fundacion Botin.S
Generation of mice with longer and better preserved telomeres in the absence of genetic manipulations
Although telomere length is genetically determined, mouse embryonic stem (ES) cells with telomeres of twice the normal size have been generated. Here, we use such ES cells with 'hyper-long' telomeres, which also express green fluorescent protein (GFP), to generate chimaeric mice containing cells with both hyper-long and normal telomeres. We show that chimaeric mice contain GFP-positive cells in all mouse tissues, display normal tissue histology and normal survival. Both hyper-long and normal telomeres shorten with age, but GFP-positive cells retain longer telomeres as mice age. Chimaeric mice with hyper-long telomeres also accumulate fewer cells with short telomeres and less DNA damage with age, and express lower levels of p53. In highly renewing compartments, such as the blood, cells with hyper-long telomeres are longitudinally maintained or enriched with age. We further show that wound-healing rates in the skin are increased in chimaeric mice. Our work demonstrates that mice with functional, longer and better preserved telomeres can be generated without the need for genetic manipulations, such as TERT overexpression.M. A. Blasco’s laboratory is funded by the Spanish Ministry of Economy and Competitiveness Project SAF2013-45111RETOS, the European Union FP7 Project EUROBATS, the European Research Council (ERC) Project TEL STEM CELL (GA#232854), the Regional Government of Madrid 2þ2 ReCaRe, the AXA Research Fund and the Fundacion BotınS
Estudio del yeísmo en el español de Barcelona a partir de materiales de PRESEEA
En enero de 2006, el equipo de investigación sociolingüística de la Universidad de
Barcelona, integrado por profesores y doctorandos del Departamento de Filología
Hispánica, se incorporó al Proyecto para el Estudio Sociolingüístico del Español de
España y de América (PRESEEA), vinculado a la Asociación de Lingüística y Filología
de América Latina (ALFAL), y que tiene como coordinador general a Francisco
Moreno Fernández, Catedrático de Lengua Española de la Universidad de Alcalá. Dicho
proyecto se organiza en una red internacional de equipos de investigación cuyo objetivo
central es el de reunir un ingente corpus oral, sociolingüísticamente representativo, de
un gran número de ciudades pertenecientes al mundo hispánico. La primera fase del
proyecto, que se presentó en 1996, abarca hasta el año 2010 (Moreno Fernández 2006).1
Para el estudio de Barcelona, en el seno del grupo PRESEEA – BARCELONA – ES
diseñamos una plantilla que contempla una representación de 108 informantes (los
cuales deben haber nacido en la ciudad, haber llegado a ella antes de cumplir los diez
años o llevar viviendo en el lugar más de veinte), distribuidos en tres variables de
preestratificación: sexo, edad y nivel de instrucción. A este perfil general añadimos la
variable ‘lengua primera’ (catalán / español), vista la repercusión que alcanza la
convivencia de las dos lenguas en la ciudad (Torres 2007).
En las páginas que siguen, nos proponemos abordar el avance real del yeísmo en la
Ciudad Condal a partir de unas muestras seleccionadas de los datos de PRESEEABARCELONA-
ES. El trabajo, que básicamente es de carácter fonético y presenta un
análisis acústico centrado en aspectos frecuenciales, de duración y de intensidad de las
muestras mencionadas, pretende ser un primer acercamiento al estadio en el que se encuentra el fenómeno en esta área específica
NSMCE2 suppresses cancer and aging in mice independently of its SUMO ligase activity.
The SMC5/6 complex is the least understood of SMC complexes. In yeast, smc5/6 mutants phenocopy mutations in sgs1, the BLM ortholog that is deficient in Bloom's syndrome (BS). We here show that NSMCE2 (Mms21, in Saccharomyces cerevisiae), an essential SUMO ligase of the SMC5/6 complex, suppresses cancer and aging in mice. Surprisingly, a mutation that compromises NSMCE2-dependent SUMOylation does not have a detectable impact on murine lifespan. In contrast, NSMCE2 deletion in adult mice leads to pathologies resembling those found in patients of BS. Moreover, and whereas NSMCE2 deletion does not have a detectable impact on DNA replication, NSMCE2-deficient cells also present the cellular hallmarks of BS such as increased recombination rates and an accumulation of micronuclei. Despite the similarities, NSMCE2 and BLM foci do not colocalize and concomitant deletion of Blm and Nsmce2 in B lymphocytes further increases recombination rates and is synthetic lethal due to severe chromosome mis-segregation. Our work reveals that SUMO- and BLM-independent activities of NSMCE2 limit recombination and facilitate segregation; functions of the SMC5/6 complex that are necessary to prevent cancer and aging in mice.The authors want to thank Jordi Torres and Mark O'Driscoll for comments on the manuscript. Work in OF laboratory related to this project was supported by Fundacion Botin, by Banco Santander through its Santander Universities Global Division and by grants from MINECO (SAF2011-23753 and SAF2014-57791-REDC), Howard Hughes Medical Institute, and the European Research Council (ERC-617840). Work in JM laboratory was funded by a grant from MINECO (BFU2013-49153P).S
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