Molecular Machines in the Synapse: Overlapping Protein Sets Control Distinct Steps in Neurosecretion

Activity regulated neurotransmission shapes the computational properties of a neuron and involves the concerted action of many proteins. Classical, intuitive working models often assign specific proteins to specific steps in such complex cellular processes, whereas modern systems theories emphasize more integrated functions of proteins. To test how often synaptic proteins participate in multiple steps in neurotransmission we present a novel probabilistic method to analyze complex functional data from genetic perturbation studies on neuronal secretion. Our method uses a mixture of probabilistic principal component analyzers to cluster genetic perturbations on two distinct steps in synaptic secretion, vesicle priming and fusion, and accounts for the poor standardization between different studies. Clustering data from 121 perturbations revealed that different perturbations of a given protein are often assigned to different steps in the release process. Furthermore, vesicle priming and fusion are inversely correlated for most of those perturbations where a specific protein domain was mutated to create a gain-of-function variant. Finally, two different modes of vesicle release, spontaneous and action potential evoked release, were affected similarly by most perturbations. This data suggests that the presynaptic protein network has evolved as a highly integrated supramolecular machine, which is responsible for both spontaneous and activity induced release, with a group of core proteins using different domains to act on multiple steps in the release process

Protocol for the establishment and characterization of an endometrial-derived epithelial organoid and stromal cell co-culture system

Summary: Postnatal development of the uterus involves the specification of undifferentiated epithelium into uterine-type epithelium. That specification is regulated by stromal-epithelial interactions as well as intrinsic cell-specific transcription factors and gene regulatory networks. Here, we present a co-culture system to study the effects of stromal-derived factors on epithelial cell growth and differentiation into organoids. First, we describe epithelial cell isolation and organoid growth characterization. Second, we detail a co-culture system that allows the study of stromal-derived paracrine factors on epithelial development.For complete details on the use and execution of this protocol, please refer to Rizo et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics

Diferencias en nodulación y desarrollo de líneas avanzadas de frijol común (Phaseolus vulgaris L.) en suelos deficientes en nitrógeno

24 p.El frijol (Phaseolus vulgaris L.) es un cultivo de importancia económica por su valiosa contribución de proteínas en la dieta de la mayoría de habitantes en países de África y América Latina. Posee la capacidad de fijar nitrógeno atmosférico al asociarse con bacterias del género Rhizobium, lo que le permite adaptarse a suelos con bajo contenido de este nutrimento. El objetivo del presente estudio fue evaluar 25 genotipos de frijol común, incluyendo 23 líneas avanzadas y dos testigos, Amadeus 77 (mejorado) y Seda (criollo), en condiciones de bajo contenido de nitrógeno, a través de tres ensayos. El primer ensayo consistió en la evaluación en campo en La Vega 5, Zamorano, en un suelo de bajo contenido de materia orgánica y N total, limitantes frecuentemente presentes en fincas de pequeños productores de frijol en Centro América. El segundo ensayo se realizó en casa malla, utilizando un sistema de canaletas con un medio inerte de arena gruesa con el objetivo de evaluar la nodulación temprana (velocidad de nodulación) de las 25 líneas de frijol inoculadas con las cepas CIAT 632 (R. tropici) y CIAT 899 (R. etli). El último ensayo se realizó en bancales o camas de 1.2 m ancho x 20 m largo con un sustrato suelo: arena (1:1) bajo en M.O. y N total, con el fin de evaluar la nodulación y producción de biomasa bajo estas condiciones. En los ensayos se midieron además de la nodulación, los pesos secos de follaje, vainas y semillas, y los índices de partición de vainas (IPV) y de cosecha (IC). Se encontraron diferencias en rendimiento, IPV, IC y peso seco de 100 semillas por efectos de genotipos en el ensayo de campo; efecto de cepas de Rhizobium en la nodulación en el ensayo de canaletas en casa de malla; y diferencias en peso seco de nódulos de los genotipos de frijol en los bancales

Estrogen receptor alpha regulates uterine epithelial lineage specification and homeostasis

Summary: Postnatal development of the uterus involves specification of undifferentiated epithelium into uterine-type epithelium. That specification is regulated by stromal-epithelial interactions as well as intrinsic cell-specific transcription factors and gene regulatory networks. This study utilized mouse genetic models of Esr1 deletion, endometrial epithelial organoids (EEO), and organoid-stromal co-cultures to decipher the role of Esr1 in uterine epithelial development. Organoids derived from wild-type (WT) mice developed a normal single layer of columnar epithelium. In contrast, EEO from Esr1 null mice developed a multilayered stratified squamous type of epithelium with basal cells. Co-culturing Esr1 null epithelium with WT uterine stromal fibroblasts inhibited basal cell development. Of note, estrogen treatment of EEO-stromal co-cultures and Esr1 conditional knockout mice increased basal epithelial cell markers. Collectively, these findings suggest that Esr1 regulates uterine epithelium lineage plasticity and homeostasis and loss of ESR1 promotes altered luminal-to-basal differentiation driven by ESR1-mediated paracrine factors from the stroma

Patterns of oral anticoagulant use and outcomes in Asian patients with atrial fibrillation: a post-hoc analysis from the GLORIA-AF Registry

Background: Previous studies suggested potential ethnic differences in the management and outcomes of atrial fibrillation (AF). We aim to analyse oral anticoagulant (OAC) prescription, discontinuation, and risk of adverse outcomes in Asian patients with AF, using data from a global prospective cohort study. Methods: From the GLORIA-AF Registry Phase II-III (November 2011-December 2014 for Phase II, and January 2014-December 2016 for Phase III), we analysed patients according to their self-reported ethnicity (Asian vs. non-Asian), as well as according to Asian subgroups (Chinese, Japanese, Korean and other Asian). Logistic regression was used to analyse OAC prescription, while the risk of OAC discontinuation and adverse outcomes were analysed through Cox-regression model. Our primary outcome was the composite of all-cause death and major adverse cardiovascular events (MACE). The original studies were registered with ClinicalTrials.gov, NCT01468701, NCT01671007, and NCT01937377. Findings: 34,421 patients were included (70.0 ± 10.5 years, 45.1% females, 6900 (20.0%) Asian: 3829 (55.5%) Chinese, 814 (11.8%) Japanese, 1964 (28.5%) Korean and 293 (4.2%) other Asian). Most of the Asian patients were recruited in Asia (n = 6701, 97.1%), while non-Asian patients were mainly recruited in Europe (n = 15,449, 56.1%) and North America (n = 8378, 30.4%). Compared to non-Asian individuals, prescription of OAC and non-vitamin K antagonist oral anticoagulant (NOAC) was lower in Asian patients (Odds Ratio [OR] and 95% Confidence Intervals (CI): 0.23 [0.22-0.25] and 0.66 [0.61-0.71], respectively), but higher in the Japanese subgroup. Asian ethnicity was also associated with higher risk of OAC discontinuation (Hazard Ratio [HR] and [95% CI]: 1.79 [1.67-1.92]), and lower risk of the primary composite outcome (HR [95% CI]: 0.86 [0.76-0.96]). Among the exploratory secondary outcomes, Asian ethnicity was associated with higher risks of thromboembolism and intracranial haemorrhage, and lower risk of major bleeding. Interpretation: Our results showed that Asian patients with AF showed suboptimal thromboembolic risk management and a specific risk profile of adverse outcomes; these differences may also reflect differences in country-specific factors. Ensuring integrated and appropriate treatment of these patients is crucial to improve their prognosis. Funding: The GLORIA-AF Registry was funded by Boehringer Ingelheim GmbH

Correction to: Comparative effectiveness and safety of non-vitamin K antagonists for atrial fibrillation in clinical practice: GLORIA-AF Registry

International audienceIn this article, the name of the GLORIA-AF investigator Anastasios Kollias was given incorrectly as Athanasios Kollias in the Acknowledgements. The original article has been corrected