20 research outputs found
Identification of PNG kinase substrates uncovers interactions with the translational repressor TRAL in the oocyte-to-embryo transition
The Drosophila Pan Gu (PNG) kinase complex regulates hundreds of maternal mRNAs that become translationally repressed or activated as the oocyte transitions to an embryo. In a previous paper (Hara et al., 2017), we demonstrated PNG activity is under tight developmental control and restricted to this transition. Here, examination of PNG specificity showed it to be a Thrkinase yet lacking a clear phosphorylation site consensus sequence. An unbiased biochemical screen for PNG substrates identified the conserved translational repressor Trailer Hitch (TRAL). Phosphomimetic mutation of the PNG phospho-sites in TRAL reduced its ability to inhibit translation in vitro. In vivo, mutation of tral dominantly suppressed png mutants and restored Cyclin B protein levels. The repressor Pumilio (PUM) has the same relationship with PNG, and we also show that PUM is a PNG substrate. Furthermore, PNG can phosphorylate BICC and ME31B, repressors that bind TRAL in cytoplasmic RNPs. Therefore, PNG likely promotes translation at the oocyte-to-embryo transition by phosphorylating and inactivating translational repressors.National Institutes of Health (U.S.) (Grant GM39341)National Institutes of Health (U.S.) (Grant GM118090
Strategic educational aspects of professional training for “Administration and Management” in the context of the international strategic security and defence environment
The main goal of the military education system, namely - to provide a high level of education in the field of security and defence, in particular the training and subsequent professional realisation of logistics officers, is based on providing effective training to the main target groups of the Vasil Levski National Military University - cadets and students. The main goal of this paper is to present educational aspects of the professional field for “Administration and Management” in the context of the international strategic security and defence environment in the Vasil Levski National Military University. As well as to show expected scholarly and educational results of international, national and local significance
Strategic Framework of Professional Preparation of Trainees in the Field of Security and Defense, Professional Field of Administration and Management : Socio-Demographic and Educational Aspects
Objectives: To clarify the factors that influence the individual’s career orientation and professional fulfillment of cadets, which can be deeply personal as well as dictated and conditioned by the external environment. Methods: A Survey of trainee opinion in the professional field of Administration and Management at the National Military University. Results: The study focuses on the socio-demographic and educational aspects of the need for training in the professional field of Administration and Management, following the example of the Department of Security Logistics, National Military University, Bulgaria. Respondents in the survey were 164 trainees from 5 consecutive years of study in the Bachelor's degree program in the professional field of “Military Affairs”. Conclusions: It is necessary to direct its efforts to recruit future trainees mainly from secondary schools, vocational high schools of economics and vocational high schools of mechanical and electrical engineering, trainees from families with low- and middle-income, trainees with strong personal motivation to practice the military profession, trainees who achieve high results in their education. The information channels for accessing better, timely and reliable information about the applying process and training at the Vasil Levski National Military University should be expanded using social networks, media and more information campaigns in schools. To a large extent, parental opinion about trainees’ choice of the military profession, also has an influence which was found to be very positive
Dissecting the role of Aurora A during spindle assembly
The centrosomal kinase Aurora A (AurA) is required for cell cycle progression, centrosome maturation and spindle assembly. However, the way it participates in spindle assembly is still quite unclear. Using the Xenopus egg extract system, we have dissected the role of AurA in the different microtubule (MT) assembly pathways involved in spindle formation. We developed a new tool based on the activation of AurA by TPX2 to clearly define the requirements for localization and activation of the kinase during spindle assembly. We show that localized AurA kinase activity is required to target factors involved in MT nucleation and stabilization to the centrosome, therefore promoting the formation of a MT aster. In addition, AurA strongly enhances MT nucleation mediated by the Ran pathway through cytoplasmic phosphorylation. Altogether, our data show that AurA exerts an effect as a key regulator of MT assembly during M phase and therefore of bipolar spindle formation
Optimized Mass Spectrometry Detection of Thyroid Hormones and Polar Metabolites in Rodent Cerebrospinal Fluid
Thyroid hormones (TH) are required for brain development and function. Cerebrospinal fluid (CSF), which bathes the brain and spinal cord, contains TH as free hormones or as bound to transthyretin (TTR). Tight TH level regulation in the central nervous system is essential for developmental gene expression, which governs neurogenesis, myelination, and synaptogenesis. This integrated function of TH highlights the importance of developing precise and reliable methods for assessing TH levels in CSF. We report an optimized liquid chromatography–mass spectrometry (LC-MS)-based method to measure TH in rodent CSF and serum, applicable to both fresh and frozen samples. Using this new method, we find distinct differences in CSF TH in pregnant dams vs. non-pregnant adults and in embryonic vs. adult CSF. Further, targeted LC-MS metabolic profiling uncovers distinct central carbon metabolism in the CSF of these populations. TH detection and metabolite profiling of related metabolic pathways open new avenues of rigorous research into CSF TH and will inform future studies on metabolic alterations in CSF during normal development
Dynamic redox balance directs the oocyte-to-embryo transition via developmentally controlled reactive cysteine changes
The metabolic and redox state changes during the transition from an arrested oocyte to a totipotent embryo remain uncharacterized. Here, we applied state-of-the-art, integrated methodologies to dissect these changes in Drosophila. We demonstrate that early embryos have a more oxidized state than mature oocytes. We identified specific alterations in reactive cysteines at a proteome-wide scale as a result of this metabolic and developmental transition. Consistent with a requirement for redox change, we demonstrate a role for the ovary-specific thioredoxin Deadhead (DHD). dhd-mutant oocytes are prematurely oxidized and exhibit meiotic defects. Epistatic analyses with redox regulators link dhd function to the distinctive redox-state balance set at the oocyte-to-embryo transition. Crucially, global thiol-redox profiling identified proteins whose cysteines became differentially modified in the absence of DHD. We validated these potential DHD substrates by recovering DHD-interaction partners using multiple approaches. One such target, NO66, is a conserved protein that genetically interacts with DHD, revealing parallel functions. As redox changes also have been observed in mammalian oocytes, we hypothesize a link between developmental control of this cell-cycle transition and regulation by metabolic cues. This link likely operates both by general redox state and by changes in the redox state of specific proteins. The redox proteome defined here is a valuable resource for future investigation of the mechanisms of redox-modulated control at the oocyte-to-embryo transition
Разпространение на хронично бъбречно заболяване сред населението на град Варна, Община Вълчи дол и Община Аврен
В световен мащаб хроничното бъбречно заболяване (ХБЗ) представлява нарастващ по тежест здравословен и икономически проблем. Според данните от Световния бъбречен ден близо 850 милиона хора по света страдат от ХБЗ с различна етиология, като 2,4 милиона души годишно умират от бъбречни заболявания. Тази честота поставя ХБЗ като 6-ата най-бързо зачестяваща причина за смъртност сред населението. Във финансов план лечението на терминалната бъбречна недостатъчност (ESRD) представлява огромна тежест за всяка държава, като хемодиализата се нарежда сред най-натоварващите бюджета на една държава вид лечение. По повод Световния бъбречен ден 2019 (14 март), Клиниката по нефрология на УМБАЛ „Св. Марина“ – Варна проведе безплатна скрининг кампания сред населението на град Варна, като поради големия интерес бяха обхванати и две общини във Варненска област – Аврен и Вълчи дол. Целта на програмата с мото „Здраве за всеки, навсякъде“ бе да открие латентно протичащи бъбречни заболявания, да акцентира върху най-сериозните рискови фактори, които биха довели до развитието на ХБЗ, както и да изостри вниманието на обществото към провежданата паралелно с програмата инициатива за донорство и трансплантация. В резултат на проведената кампания бяха обхванати общо 195 души, като при 75 от тях се откри хронично бъбречно заболяване, а 120 бяха без обективни данни за бъбречна патология. Получените данни дават основание да се смята, че са необходими по-мащабни стратегии за диагностика и превенция на хроничното бъбречно заболяване, което би се отразило благоприятно както върху здравния статус на населението, така и на финансовото и икономическо положение на държавата
Early clinical and electrophysiologic features of the two most common autosomal recessive forms of Charcot-Marie-Tooth disease in the Roma (Gypsies)
Genetic screens reveal a central role for heme metabolism in artemisinin susceptibility
© 2020, The Author(s). Artemisinins have revolutionized the treatment of Plasmodium falciparum malaria; however, resistance threatens to undermine global control efforts. To broadly explore artemisinin susceptibility in apicomplexan parasites, we employ genome-scale CRISPR screens recently developed for Toxoplasma gondii to discover sensitizing and desensitizing mutations. Using a sublethal concentration of dihydroartemisinin (DHA), we uncover the putative transporter Tmem14c whose disruption increases DHA susceptibility. Screens performed under high doses of DHA provide evidence that mitochondrial metabolism can modulate resistance. We show that disrupting a top candidate from the screens, the mitochondrial protease DegP2, lowers porphyrin levels and decreases DHA susceptibility, without significantly altering parasite fitness in culture. Deleting the homologous gene in P. falciparum, PfDegP, similarly lowers heme levels and DHA susceptibility. These results expose the vulnerability of heme metabolism to genetic perturbations that can lead to increased survival in the presence of DHA