Analysis of gene network bifurcation during optic cup morphogenesis in zebrafish

Sight depends on the tight cooperation between photoreceptors and pigmented cells, which derive from common progenitors through the bifurcation of a single gene regulatory network into the neural retina (NR) and retinal-pigmented epithelium (RPE) programs. Although genetic studies have identified upstream nodes controlling these networks, their regulatory logic remains poorly investigated. Here, we characterize transcriptome dynamics and chromatin accessibility in segregating NR/RPE populations in zebrafish. We analyze cis-regulatory modules and enriched transcription factor motives to show extensive network redundancy and context-dependent activity. We identify downstream targets, highlighting an early recruitment of desmosomal genes in the flattening RPE and revealing Tead factors as upstream regulators. We investigate the RPE specification network dynamics to uncover an unexpected sequence of transcription factors recruitment, which is conserved in humans. This systematic interrogation of the NR/RPE bifurcation should improve both genetic counseling for eye disorders and hiPSCs-to-RPE differentiation protocols for cell-replacement therapies in degenerative diseases.This work is supported by the following grants: (I) To J.-R.M.-M.: From the Spanish Ministry of Science, Innovation, and Universities (MICINN): BFU2017-86339P with FEDER funds, MDM-2016-0687 and PY20_00006/Junta de Andalucía. (II) To O.B. Australian Research Council (ARC) Discovery Project (DP190103852). (III) To F.-J.D.-C.: Andalusian Ministry of Health, Equality and Social Policies (PI-0099-2018). (IV) To P.B.: BFU2016-75412-R with FEDER funds; PCIN-2015-176-C02-01/ERA-Net Neuron ImprovVision, and a CBMSO Institutional grant from the Fundación Ramón Areces. (V) To both J.-R.M.-M. and P.B.: BFU2016-81887-REDT, as well as Fundación Ramón Areces-2016 (Supporting L.B.)

A Functional Pipeline of Genome-Wide Association Data Leads to Midostaurin as a Repurposed Drug for Alzheimer’s Disease

Genome-wide association studies (GWAS) constitute a powerful tool to identify the different biochemical pathways associated with disease. This knowledge can be used to prioritize drugs targeting these routes, paving the road to clinical application. Here, we describe DAGGER (Drug Repositioning by Analysis of GWAS and Gene Expression in R), a straightforward pipeline to find currently approved drugs with repurposing potential. As a proof of concept, we analyzed a meta-GWAS of 1.6 × 107 single-nucleotide polymorphisms performed on Alzheimer’s disease (AD). Our pipeline uses the Genotype-Tissue Expression (GTEx) and Drug Gene Interaction (DGI) databases for a rational prioritization of 22 druggable targets. Next, we performed a two-stage in vivo functional assay. We used a C. elegans humanized model over-expressing the Aβ1-42 peptide. We assayed the five top-scoring candidate drugs, finding midostaurin, a multitarget protein kinase inhibitor, to be a protective drug. Next, 3xTg AD transgenic mice were used for a final evaluation of midostaurin’s effect. Behavioral testing after three weeks of 20 mg/kg intraperitoneal treatment revealed a significant improvement in behavior, including locomotion, anxiety-like behavior, and new-place recognition. Altogether, we consider that our pipeline might be a useful tool for drug repurposing in complex diseases.This work was mainly financed by Programa Operativo FEDER funds from the European Union through grant UMA20-FEDERJA-133. We thank Fundacion SantÁngela for co-funding with grant 83/23.04.2021. P.G.-G. is supported by the CIBERNED employment plan CNV-304-PRF-866. CIBERNED is integrated into Instituto de Salud Carlos III. I.d.R is supported by a national grant from the Instituto de Salud Carlos III FI20/00215. A.R. is supported by national grants PI13/02434, PI16/01861, PI17/01474, PI19/01240, and PI19/01301. A.M.B.-L. and M.J.M. were funded by grant PID2020-120463RB-I00 funded by the Spanish Ministerio de Ciencia e Innovación. A.C.-Z. holds a postdoctoral research contract from Secretaría General de Universidades, Investigación y Tecnología–Junta de Andalucía (POSTDOC21_00365). B.P.S (IFI21/00024) holds an “iPFIS” predoctoral contract from the National System of Health, EU-ERDF-ISCIII. M.d.C.M.-P. holds predoctoral grants from the Spanish Ministry of Science, Innovation and Universities (FPU17/00276). P.R. (CP19/00068) holds a “Miguel Servet” research contract from the National System of Health, ISCIII co-funded by the European Social Fund, “Investing in your future,” Gobierno de España. This research was funded by Delegación del Gobierno para el Plan Nacional sobre Drogas, Ministerio de Salud, Gobierno de España (PND2020/048). Ethovision XT software v17 (Noldus, Wageningen, The Netherlands) funded by Plan Propio, Universidad de Málaga

Nanoestructuras biocidas

Esta invención se refiere a un procedimiento de obtención de nanoestructuras que comprende las siguientes etapas: a) preparación de una suspensión que comprende al menos un óxido metálico semiconductor, carbón activo y al menos un compuesto de un metal noble; y b) adición de un agente reductor a la suspensión obtenida en la etapa (a).Peer reviewedUniversidad Pablo de Olavide, Consejo Superior de Investigaciones CientíficasA1 Solicitud de patente con informe sobre el estado de la técnic

Nanoestructuras biocidas

Esta invención se refiere a un procedimiento de obtención de nanoestructuras que comprende las siguientes etapas: a) preparación de una suspensión que comprende al menos un óxido metálico semiconductor, carbón activo y al menos un compuesto de un metal noble; y b) adición de un agente reductor a la suspensión obtenida en la etapa (a).Peer reviewedUniversidad Pablo de Olavide, Consejo Superior de Investigaciones CientíficasB1 Patente sin examen previ

Maob rs3027452 modifies mood improvement after tryptophan supplementation

© 2021 Gonzalez et al.[Purpose]: Tryptophan is the only precursor of serotonin, the hormone which helps regulate key human functions such as appetite, memory, mood, and sexual behavior. Connections have been identified between serotonin system dysfunction and the molecular etiology and treatment of mood disorders in a wide range of studies. Proposals have been put forward to co-administer tryptophan supplementation together with serotonin reuptake inhibitors in major depression patients, and also to exploit the sub-therapeutic depressive status in healthy populations. The reported responses, however, have been very dissimilar and this uneven effect may largely be explained by interindividual genetic differences.[Materials and Methods]: We studied mood change in 138 healthy subjects using both Goldberg’s General Health Questionnaire and the Profile of Mood States Questionnaire to determine the effects of a daily supplementation of 1g of tryptophan or placebo. Buccal DNA samples were provided and TPH1 (rs1800532), MAOA (rs3788862 and rs979605), MAOB (rs3027452), and COMT (rs6269 and rs4680) variants were genotyped.[Results]: MAOB rs3027452 was equally associated with tryptophan supplementation efficacy in the depression subscales of both questionnaires (ΔT-Score.D; ΔT-Score.TMD and ΔPOMS.D p-values < 0.01).[Conclusion]: Here we provide evidence that tryptophan supplementation has an uneven effect on mood improvement in the general population

Dysmorphic contribution of neurotransmitter and neuroendocrine system polymorphisms to subtherapeutic mood states

© The Author(s).[Objective]: From an evolutionary perspective, emotions emerged as rapid adaptive reactions that increase survival rates. Current psychobiology includes the consideration that genetic changes affecting neuroendocrine and neurotransmission pathways may also be affecting mood states. Following this hypothesis, abnormal levels of any of the aminergic neurotransmitters would be of considerable importance in the development of a pathophysiological state. [Materials and Methods]: A total of 668 students from the School of Medicine of the University of Malaga (Average = 22.41 ± 3; 41% men) provided self‐report measures of mood states using POMS and GHQ‐28 questionnaires and buccal cells for genotyping 19 polymorphisms from 14 selected neurotransmitter pathways genes (HTR1A; HTR2A; HTR2C; HTR3B; TPH1; SLC18A1; SLC18A2; COMT; MAOA; MAOB) and neuroendocrine system (AVPR1B; OPRM1; BDNF; OXTR). [Results]: MAOA rs3788862 genotype correlates with decreasing levels of Tension among females (beta = −0.168, p‐value = 0.003) but it is neutral among males in this subscale. On the contrary, it correlates with lower GHQ‐28 depression scores among males (beta = −0.196, p‐value = 0.008). Equivalently, SLC18A1 and HTR2A variants correlated with anger and vigor scores, only among males. From the neuroendocrine system, OPRM1 rs1799971 correlated increasing levels of female's Anxiety, depression and Social Dysfunction scores. [Conclusion]: Our findings suggest that these polymorphisms contribute to define general population mood levels, although exhibiting a clear sexual dimorphism

Nanoestructuras biocidas

[EN] The invention relates to a method for producing nanostructures, comprising the following steps: a) preparing a suspension comprising at least one semiconductive metal oxide, activated carbon and at least one compound of a noble metal; and b) adding a reducing agent to the suspension obtained in step (a).[ES] Esta invención se refiere a un procedimiento de obtención de nanoestructuras que comprende las siguientes etapas:a) preparación de una suspensión que comprende al menos un óxido metálico semiconductor, carbón activo y al menos un compuesto de un metal noble;y b) adición de un agente reductor a la suspensión obtenida en la etapa (a).Peer reviewedUniversidad Pablo de Olavide, Consejo Superior de Investigaciones CientíficasA1 Solicitud de patente con informe sobre el estado de la técnic

Analysis of cellular behavior and cytoskeletal dynamics reveal a constriction mechanism driving optic cup morphogenesis

Contractile actomyosin networks have been shown to power tissue morphogenesis. Although the basic cellular machinery generating mechanical tension appears largely conserved, tensions propagate in unique ways within each tissue. Here we use the vertebrate eye as a paradigm to investigate how tensions are generated and transmitted during the folding of a neuroepithelial layer. We record membrane pulsatile behavior and actomyosin dynamics during zebrafish optic cup morphogenesis by live imaging. We show that retinal neuroblasts undergo fast oscillations and that myosin condensation correlates with episodic contractions that progressively reduce basal feet area. Interference with lamc1 function impairs basal contractility and optic cup folding. Mapping of tensile forces by laser cutting uncover a developmental window in which local ablations trigger the displacement of the entire tissue. Our work shows that optic cup morphogenesis is driven by a constriction mechanism and indicates that supra-cellular transmission of mechanical tension depends on ECM attachment.The authors wish to thank the financial support given to M N-P by the FPI-MICINN program. This work was supported by grants BFU2011-22916, P11-CVI-7256, BFU2014-53765 and BFU2014-55738-REDT to JRMM.Peer Reviewe

Comprehensive Toxicity Assessment of PEGylated Magnetic Nanoparticles for in vivo applications

Magnetic nanoparticles (MNPs) represent one of the greatest promises for the development of a new generation of diagnostic agents for magnetic resonance imaging, with improved specificity and safety. Indeed, during the last decade the number of studies published in this field has grown exponentially. However, the clinical translation achieved so far has been very limited. This situation is likely related to the fact that most studies are focused on the in vitro characterization of these new nanomaterials, and very few provide an exhaustive in vivo characterization, where key aspects, such as pharmacokinetics, bioavailability, and, most importantly, toxicity, are properly evaluated. In this work, we propose a protocol for the comprehensive assessment of the toxicity of MNPs, based on the use of zebrafish embryos as an intermediate screening step between cell culture assays and studies in rodents. MNPs with different cores, ferrite and manganese ferrite oxide, and sizes between 3 and 20 nm, were evaluated. Cell viability at a concentration of 50 μg/mL of PEGylated MNPs was above 90 % in all cases. However, the exposure of zebrafish embryos to manganese based MNPs at concentrations above 100 μg/mL showed a low survival rate (<50 %). In contrast, no mortality (survival rate ∼100 %) and normal hatching rate were obtained for the iron oxide MNPs. Based on these results, together with the physicochemical and magnetic properties (r2 = 153.6 mM-1·s-1), the PEGylated 20 nm cubic shape iron oxide MNPs were selected and tested in mice, showing very good MRI contrast and, as expected, absence of toxicity.Financial support was provided by the Andalusian Ministry of Health (PI2013-0559 to MPL), the Spanish Ministry of Economy and Competitiveness (CTQ2017-86655-R to MPL and MLGM). MPL thanks to the V Plan Propio of the University of Seville for the Postdoctoral Fellowship

Evolutionary emergence of the rac3b/rfng/sgca regulatory cluster refined mechanisms for hindbrain boundaries formation

Letelier, Joaquin et al.Developmental programs often rely on parallel morphogenetic mechanisms that guarantee precise tissue architecture. While redundancy constitutes an obvious selective advantage, little is known on how novel morphogenetic mechanisms emerge during evolution. In zebrafish, rhombomeric boundaries behave as an elastic barrier, preventing cell intermingling between adjacent compartments. Here, we identify the fundamental role of the small-GTPase Rac3b in actomyosin cable assembly at hindbrain boundaries. We show that the novel rac3b/rfng/sgca regulatory cluster, which is specifically expressed at the boundaries, emerged in the Ostariophysi superorder by chromosomal rearrangement that generated new cis-regulatory interactions. By combining 4C-seq, ATAC-seq, transgenesis, and CRISPR-induced deletions, we characterized this regulatory domain, identifying hindbrain boundary-specific cis-regulatory elements. Our results suggest that the capacity of boundaries to act as an elastic mesh for segregating rhombomeric cells evolved by cooption of critical genes to a novel regulatory block, refining the mechanisms for hindbrain segmentation.This work was supported by La Marató-TV3 Grant 345/C/2014 (to C.P.), “Equipe FRM” (to S.R.), and the Spanish Ministry of Economy and Competitiveness [MINECO-FEDER; Grants BFU2012-31994 and BFU2015-67400-P (to C.P.)], Unidad de Excelencia María de Maetzu [Grants MDM-2014-0370 to DCEXS-UPF (Department of Experimental and Health Sciences-Universitat Pompeu Fabra); BFU2011-22916, P11-CVI-7256, BFU2014-53765, and BFU2014-55738-REDT (to J.R.M.-M.); and BFU2016-81887-REDT/AEI (to J.R.M.-M. and C.P.)]. J.L. and C.A.U. were funded by postdoctoral fellowships from the Becas Chile program (CONICYT, Chile). J.T. was a recipient of a postdoctoral Beatriu de Pinos fellowship (AGAUR, Generalitat de Catalunya), A.V. is a recipient of a predoctoral fellowship from LaCaixa, and I.B. holds a predoctoral Fromació d’Investigadors (FI) fellowship (AGAUR, Generalitat de Catalunya). C.P. is a recipient of an ICREA Academia Award (Institució Catalana per la Recerca i Estudis Avançats, Generalitat de Catalunya). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant 658521 (to I.M.).Peer reviewe