The Eutherian Armcx genes regulate mitochondrial trafficking in neurons and interact with Miro and Trak2

Producción CientíficaBrain function requires neuronal activity-dependent energy consumption. Neuronal energy supply is controlled by molecular mechanisms that regulate mitochondrial dynamics, including Kinesin motors and Mitofusins, Miro1-2 and Trak2 proteins. Here we show a new protein family that localizes to the mitochondria and controls mitochondrial dynamics. This family of proteins is encoded by an array of armadillo (Arm) repeat-containing genes located on the X chromosome. The Armcx cluster is unique to Eutherian mammals and evolved from a single ancestor gene (Armc10). We show that these genes are highly expressed in the developing and adult nervous system. Furthermore, we demonstrate that Armcx3 expression levels regulate mitochondrial dynamics and trafficking in neurons, and that Alex3 interacts with the Kinesin/Miro/Trak2 complex in a Ca2 + -dependent manner. Our data provide evidence of a new Eutherian-specific family of mitochondrial proteins that controls mitochondrial dynamics and indicate that this key process is differentially regulated in the brain of higher vertebrates.2015-03-3

Toward the RNA-World in the Interstellar Medium-Detection of Urea and Search of 2-Amino-oxazole and Simple Sugars

In the past decade, astrochemistry has witnessed an impressive increase in the number of detections of complex organic molecules. Some of these species are of prebiotic interest such as glycolaldehyde, the simplest sugar, or aminoacetonitrile, a possible precursor of glycine. Recently, we have reported the detection of two new nitrogen-bearing complex organics, glycolonitrile and Z-cyanomethanimine, known to be intermediate species in the formation process of ribonucleotides within theories of a primordial RNA-world for the origin of life. In this study, we present deep and high-sensitivity observations toward two of the most chemically rich sources in the galaxy: a giant molecular cloud in the center of the Milky Way (G + 0.693-0.027) and a proto-Sun (IRAS16293-2422 B). Our aim is to explore whether the key precursors considered to drive the primordial RNA-world chemistry are also found in space. Our high-sensitivity observations reveal that urea is present in G + 0.693-0.027 with an abundance of ∼5 × 10-11. This is the first detection of this prebiotic species outside a star-forming region. Urea remains undetected toward the proto-Sun IRAS16293-2422 B (upper limit to its abundance of ≤2 × 10-11). Other precursors of the RNA-world chemical scheme such as glycolaldehyde or cyanamide are abundant in space, but key prebiotic species such as 2-amino-oxazole, glyceraldehyde, or dihydroxyacetone are not detected in either source. Future more sensitive observations targeting the brightest transitions of these species will be needed to disentangle whether these large prebiotic organics are certainly present in space.With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737); This work has been partially supported by MINECO and FEDER (project numbers ESP2015-65597-C4-1, CTQ2017-89150-R, and ESP2017-86582-C4-1-R

Cruising y e-citas: un nuevo contexto para los encuentros sexuales entre hombres jóvenes que tienen sexo con hombres

Resumen El objetivo de este artículo es el de explorar el papel que juega, en la actualidad, la irrupción de la mediación tecnológica de la información y la comunicación en la configuración de nuevos contextos para la relación sexual. En concreto, hemos explorado una práctica determinada, el cruising, entre hombres jóvenes que tienen sexo con hombres contactado a través de las e-citas. Se ha apostado por la metodología cualitativa con la intención de recopilar los discursos sobre sexualidad, riesgos y salud que se generan y construyen entre el grupo de iguales. Según extraemos de nuestro estudio, el nuevo marco que confiere esta tecnología estaría caracterizado por (a) una mayor accesibilidad a dichas prácticas, (b) una mayor difusión de estas, (c) una mayor inmediatez de acceso a las propuestas, (d) la anticipación de lo que será ofrecido en la cita, (e) acceso anónimo que permite propuestas más atrevidas y (f) una apertura mayor a la diversidad de usuarios. Todos estos elementos confluyen en un cuadro que nos lleva a considerar una organización social renovada de la práctica sexual