Body-fat sensor triggers ribosome maturation in the steroidogenic gland to initiate sexual maturation in Drosophila

Fat stores are critical for reproductive success and may govern maturation initiation. Here, we report that signaling and sensing fat sufficiency for sexual maturation commitment requires the lipid carrier apolipophorin in fat cells and Sema1a in the neuroendocrine prothoracic gland (PG). Larvae lacking apolpp or Sema1a fail to initiate maturation despite accruing sufficient fat stores, and they continue gaining weight until death. Mechanistically, sensing peripheral body-fat levels via the apolipophorin/Sema1a axis regulates endocytosis, endoplasmic reticulum remodeling, and ribosomal maturation for the acquisition of the PG cells' high biosynthetic and secretory capacity. Downstream of apolipophorin/Sema1a, leptin-like upd2 triggers the cessation of feeding and initiates sexual maturation. Human Leptin in the insect PG substitutes for upd2, preventing obesity and triggering maturation downstream of Sema1a. These data show how peripheral fat levels regulate the control of the maturation decision-making process via remodeling of endomembranes and ribosomal biogenesis in gland cells

A method for multiple sampling mouse sperm in vivo

Mice are the most widely used animal model to study human diseases. However, the difficulty of in vivo recovery of mouse sperm has posed a limitation with its use in reproductive biology research. Several published techniques for obtaining sperm samples in vivo have been described, but most of them have several caveats. Critical limitations include poor reliability and significant mortality (Electroejaculation and drug-induced ejaculation), or the need for a large number of animals, careful programming, and laborious work (directed mating). Here, we describe a new approach for in vivo collection of sperm in the mouse via direct puncture of the epididymis to address these limitations. In addition, the technique is easy, safe and reliable, allowing the animal to recover and maintain its fertility. In this way, punctual experiments could be carried out, or even more so, serial sampling of the same animal over time. Therefore, our approach allows for long-term and time-course experiments to study sperm characteristics under different treatments or conditions while maintaining the spermatogenic niche in vivo. In summary, we present our original approach as a powerful research tool to facilitate the study of spermatozoa relevant to various areas of biomedical research.This work was supported by grants PID2021-123407OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe,” and PROMETEU/2021/027 funded by the Generalitat Valenciana to J.M. All authors have been supported by grant SEV-2017-0723 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe.”Peer reviewe

Subpallial origin of a population of projecting pioneer neurons during corticogenesis

Pyramidal neurons of the mammalian cerebral cortex are generated in the ventricular zone of the pallium whereas the subpallium provides the cortex with inhibitory interneurons. The marginal zone contains a subpial stream of migratory interneurons and two different classes of transient neurons, the pioneer neurons provided with corticofugal axons, and the reelin-expressing Cajal–Retzius cells. We found in cultured slices that the medial ganglionic eminence provides the reelin-negative pioneer neurons of the marginal zone. Pioneer neurons sent long projection axons that went through the cortical plate and reached the subplate and the lateral border of the lateral ganglionic eminence. In the cultured slices, pioneer neurons were functionally mature: they displayed a voltage-gated sodium current, expressed functional α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, and showed γ-aminobutyric acid type A (GABA(A)) postsynaptic events that were modulated by presynaptic AMPA receptors. Pioneer neurons expressed the adhesion molecules L1 and TAG-1; the latter has been reported to control tangential migrations to the neocortex [Denaxa, M., Chan, C.-H., Schachner, M., Parnavelas, J. & Karagogeos, D. (2001) Development (Cambridge, U.K.) 128, 4635–4644], and we show here that the pioneer neurons of the marginal zone are the cellular substrate of such a function. Finally, we show that, in early corticogenesis, reelin controls both the tangential migration of cortical interneurons toward the cortical plate and the tangential migration of pioneer neurons toward the marginal zone

Notational analysis of the game actions performed by female volleyball players in university competition

En los últimos años son numerosos los trabajos de investigación que han aplicado el análisis notacional al estudio del comportamiento técnico-táctico de los deportistas en contextos naturales de competición. El objetivo del presente trabajo fue describir el tipo de acciones realizadas en función del rol de juego desempeñado por jugadoras de voleibol durante la competición. Aplicando principios de análisis notacional se analizaron un total de 19635 acciones, correspondientes a 3 sets de cada uno de los 8 equipos que participaron en el Campeonato de España Universitario de Voleibol en categoría Femenina. Para la obtención de los datos se elaboraron instrumentos ad hoc de observación y registro. Dentro de las acciones realizadas por los diferentes roles de juego específicos, la central llevó a cabo más acciones de bloqueo (25,4%), la colocadora de colocación (31,6%), y la receptora, líbero y opuesta de defensa (38,5, 40,6 y 42,9%, respectivamente). El conocimiento de las acciones realizadas por las jugadoras es de gran ayuda para la optimización del rendimiento, ya que permite el diseño de tareas específicas en función del rol de las jugadoras.ABSTRACT: In recent years there have been a lot of studies that have implemented the notational analysis to the study of the technical-tactical behaviours of the athletes in competition. The aim of this study is to describe the type of actions carried out in relationship with the role of the playerby players of volleyball during the competition. Apply principles of notational analysis to a total of 19635 actions, corresponding to 3 sets of each of the 8 teams that participated in the Female Volleyball University Spanish Championship. Among the actions taken by the specific roles of the player, the middleblocker carried out more blocks (25,4%), the setter of setting (31,6%), and the receiver, libero and opposite of dig (38,5; 40,6 and 42,9%, respectively).The knowledge of the actions performed by the players is a great help in the optimization of the performance, because it allows the design of specific tasks depending on the role of the players

Raman microstructural analysis of silicon-on-insulator formed by high dose oxygen ion implantation: As-implanted structures

A microstructural analysis of silicon-on-insulator samples obtained by high dose oxygen ion implantation was performed by Raman scattering. The samples analyzed were obtained under different conditions thus leading to different concentrations of defects in the top Si layer. The samples were implanted with the surface covered with SiO2 capping layers of different thicknesses. The spectra measured from the as-implanted samples were fitted to a correlation length model taking into account the possible presence of stress effects in the spectra. This allowed quantification of both disorder effects, which are determined by structural defects, and residual stress in the top Si layer before annealing. These data were correlated to the density of dislocations remaining in the layer after annealing. The analysis performed corroborates the existence of two mechanisms that generate defects in the top Si layer that are related to surface conditions during implantation and the proximity of the top Si/buried oxide layer interface to the surface before annealing

Nuevo sistema optoelectrónico para acelerómetros de fibra óptica

The development of fiber optic transducer heads for measuring accelerations must be accompanied with the design of an optoelectronic system able to take advantage of the head characteristics. The optoelectronic system designed generates the light that will be modulated by the magnitude to be sensed. Furthermore, it detects the light received from the sensor head to produce an electric signal. This signal is processed to produce an output signal proportional to the acceleration experienced by the sensor head

A tau class glutathione-S-transferase is involved in trans-resveratrol transport out of grapevine cells

Vitis vinifera cell cultures respond to pathogens and elicitors by synthesizing and extracellularly accumulating stilbenoid phytoalexins. Large amounts of trans-resveratrol (t-R) are produced when a cell culture is elicited with methylated cyclodextrins (MBCD), either alone or combined with methyl jasmonate (MeJA). t-R transport to the extracellular medium, which represents the apoplastic space, would place this antifungal defense right in the battlefield to efficiently fight against pathogen attack. Yet despite their physiological relevance, these transport pathways are mostly unknown. A broad hypothesis-free DIGE-based proteomic experiment of a temporal series of elicited grapevine cell cultures was performed to explore the expression profiles of t-R biosynthetic proteins and other co-expressing proteins potentially involved in such a cell response. A correlation between two tau class glutathione-S-transferases (GSTs) with several stilbene synthase and phenylalanine ammonia-lyase isoforms, and with the t-R metabolite itself, was found and further assessed by a qRT-PCR gene expression analysis. The best candidate, GSTU-2, was cloned from the cDNA of the MBCD + MeJA-elicited grapevine cells and used for Agrobacterium-mediated grapevine cell transformation. The non-elicited lines that overexpressed GSTU-2 displayed an extracellular t-R accumulating phenotype, but stabilization of t-R required the addition to culture medium of adsorbent compounds, e.g., PVP or β-cyclodextrin. The wild-type cell cultures accumulated no t-R, not even in the presence of adsorbents. The transient expression of the GSTU-2-GFP fusion proteins in grapevine cells showed localisation in the plasma membrane, and the immunoprecipitation of HA-tagged GSTU-2 revealed its interaction with HIR, a plasma membrane-bound protein. These findings are consistent with a functional role in transport. This is the first report providing several pieces of experimental evidence for the involvement of a specific tau class GST in t-R transport to the extracellular medium

Temporal patterning of Drosophila medulla neuroblasts controls neural fates

In the Drosophila optic lobes, the medulla processes visual information coming from inner photoreceptors R7 and R8 and from lamina neurons. It contains ~40,000 neurons belonging to over 70 different types. We describe how precise temporal patterning of neural progenitors generates these different neural types. Five transcription factors--Homothorax, Eyeless, Sloppy-paired, Dichaete and Tailless--are sequentially expressed in a temporal cascade in each of the medulla neuroblasts as they age. Loss of either Eyeless, Sloppy-paired or Dichaete blocks further progression of the temporal sequence. We provide evidence that this temporal sequence in neuroblasts, together with Notch-dependent binary fate choice, controls the diversification of the neuronal progeny. Although a temporal sequence of transcription factors had been identified in Drosophila embryonic neuroblasts, our work illustrates the generality of this strategy, with different sequences of transcription factors being used in different contexts