Microtubule-dependent ribosome localization in C. elegans neurons.

Subcellular localization of ribosomes defines the location and capacity for protein synthesis. Methods for in vivo visualizing ribosomes in multicellular organisms are desirable in mechanistic investigations of the cell biology of ribosome dynamics. Here, we developed an approach using split GFP for tissue-specific visualization of ribosomes in Caenorhabditis elegans. Labeled ribosomes are detected as fluorescent puncta in the axons and synaptic terminals of specific neuron types, correlating with ribosome distribution at the ultrastructural level. We found that axonal ribosomes change localization during neuronal development and after axonal injury. By examining mutants affecting axonal trafficking and performing a forward genetic screen, we showed that the microtubule cytoskeleton and the JIP3 protein UNC-16 exert distinct effects on localization of axonal and somatic ribosomes. Our data demonstrate the utility of tissue-specific visualization of ribosomes in vivo, and provide insight into the mechanisms of active regulation of ribosome localization in neurons

Motor Neuron Synapse and Axon Defects in a C. elegans Alpha-Tubulin Mutant

Regulation of microtubule dynamics underlies many fundamental cellular mechanisms including cell division, cell motility, and transport. In neurons, microtubules play key roles in cell migration, axon outgrowth, control of axon and synapse growth, and the regulated transport of vesicles and structural components of synapses. Loss of synapse and axon integrity and disruption of axon transport characterize many neurodegenerative diseases. Recently, mutations that specifically alter the assembly or stability of microtubules have been found to directly cause neurodevelopmental defects or neurodegeneration in vertebrates. We report here the characterization of a missense mutation in the C-terminal domain of C. elegans alpha-tubulin, tba-1(ju89), that disrupts motor neuron synapse and axon development. Mutant ju89 animals exhibit reduction in the number and size of neuromuscular synapses, altered locomotion, and defects in axon extension. Although null mutations of tba-1 show a nearly wild-type pattern, similar axon outgrowth defects were observed in animals lacking the beta-tubulin TBB-2. Genetic analysis reveals that tba-1(ju89) affects synapse development independent of its role in axon outgrowth. tba-1(ju89) is an altered function allele that most likely perturbs interactions between TBA-1 and specific microtubule-associated proteins that control microtubule dynamics and transport of components needed for synapse and axon growth

Caenorhabditis elegans Flamingo Cadherin fmi-1 Regulates GABAergic Neuronal Development

This is the publisher's version, also available electronically from http://www.jneurosci.org/content/32/12/4196.In a genetic screen for regulators of synaptic morphology, we identified the single Caenorhabditis elegans flamingo-like cadherin fmi-1. The fmi-1 mutants exhibit defective axon pathfinding, reduced synapse number, aberrant synapse size and morphology, as well as an abnormal accumulation of synaptic vesicles at nonsynaptic regions. Although FMI-1 is primarily expressed in the nervous system, it is not expressed in the ventral D-type (VD) GABAergic motorneurons, which are defective in fmi-1 mutants. The axon and synaptic defects of VD neurons could be rescued when fmi-1 was expressed exclusively in non-VD neighboring neurons, suggesting a cell nonautonomous action of FMI-1. FMI-1 protein that lacked its intracellular domain still retained its ability to rescue the vesicle accumulation defects of GABAergic motorneurons, indicating that the extracellular domain was sufficient for this function of FMI-1 in GABAergic neuromuscular junction development. Mutations in cdh-4, a Fat-like cadherin, cause similar defects in GABAergic motorneurons. The cdh-4 is expressed by the VD neurons and seems to function in the same genetic pathway as fmi-1 to regulate GABAergic neuron development. Thus, fmi-1 and cdh-4 cadherins might act together to regulate synapse development and axon pathfinding

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

First Attempt with Maya

3d modeling and rendering is one of the thinks I really like. Talking about 3D Studio Max or Cinema 4D it was very easy to understand and I just get used to it, wile Maya is absolutely different. So I starting to learn it by myself and it seems to be very interesting. Here is the first render. It is an old silver Russian ruble

Systematic Analyses of rpm-1 Suppressors Reveal Roles for ESS-2 in mRNA Splicing in Caenorhabditis elegans

The PHR (Pam/Highwire/RPM-1) family of ubiquitin E3 ligases plays conserved roles in axon patterning and synaptic development. Genetic modifier analysis has greatly aided the discovery of the signal transduction cascades regulated by these proteins. In Caenorhabditis elegans, loss of function in rpm-1 causes axon overgrowth and aberrant presynaptic morphology, yet the mutant animals exhibit little behavioral deficits. Strikingly, rpm-1 mutations strongly synergize with loss of function in the presynaptic active zone assembly factors, syd-1 and syd-2, resulting in severe locomotor deficits. Here, we provide ultrastructural evidence that double mutants, between rpm-1 and syd-1 or syd-2, dramatically impair synapse formation. Taking advantage of the synthetic locomotor defects to select for genetic suppressors, previous studies have identified the DLK-1 MAP kinase cascade negatively regulated by RPM-1. We now report a comprehensive analysis of a large number of suppressor mutations of this screen. Our results highlight the functional specificity of the DLK-1 cascade in synaptogenesis. We also identified two previously uncharacterized genes. One encodes a novel protein, SUPR-1, that acts cell autonomously to antagonize RPM-1. The other affects a conserved protein ESS-2, the homolog of human ES2 or DGCR14. Loss of function in ess-2 suppresses rpm-1 only in the presence of a dlk-1 splice acceptor mutation. We show that ESS-2 acts to promote accurate mRNA splicing when the splice site is compromised. The human DGCR14/ES2 resides in a deleted chromosomal region implicated in DiGeorge syndrome, and its mutation has shown high probability as a risk factor for schizophrenia. Our findings provide the first functional evidence that this family of proteins regulate mRNA splicing in a context-specific manner

Пошук перспективних видів підродин Amygdaloideae та Pyroideae з використанням хемотаксономії

World flora has more than 1000 species of the genus Сrataegus L., more than 30 species belong to the subgenus Prunus L., genus Malus Mill. has 100 species, subgenus Cerasus Juss. includes more than 150 species. Despite the diversity of species and a sufficient resource base, only a few representatives of the genus sufficiently researched and found their use as sources of biologically active substances (BAS).Aim of research. To conduct a chemotaxonomic study of representatives of the genus Сrataegus L., Prunus L., Malus Mill., Cerasus Juss.; to establish a promising sources of biologically active substances for the drugs production.Materials and methods. Chemotaxonomic study was carried out using the method of the graph analysis. The chemomarkers were phenolic compounds and terpenoids, identified in the generative and vegetative organs of the representatives of the genus Сrataegus L., Prunus L., Malus Mill., Cerasus Juss. The terpenoids and organic acids were identified by a chromatography-mass-spectrometric method on an Agilent Technology 6890N chromatograph with a 5973N mass-spectrometric detector. Flavonoids and hydroxycinnamic acids were detected by chromatography.Results. The chemical profiles of vegetative and generative organs of 34 species of the genus Сrataegus L. are established, 5 species of the genus Prunus L., 7 species of the genus Malus Mill., 4 species of the genus Cerasus Juss. The promising species of hawthorn, wich accumulated a general group BAS of genus was detected.Conclusion. According to the results of a chemotaxonomic study of representatives of subgenus Amygdaloideae and Pyroideae was detected a promising sources of biologically active substances (BAS) among species of  the genus Crataegus L., Prunus L., Malus Mill. and Cerasus Juss. The chemical profiles are forming flavonoids, terpenoids and aromatic acids. The promising species of hawthorn was added to the complex «Kratophyt»Мировая флора насчитывает более 1000 видов рода Сrataegus L., к подроду Prunus L. относится более 30 видов, род Malus Mill. насчитывает 100 видов, подрод Cerasus Juss. включает более 150 видов. Несмотря на разнообразие видов и достаточную сырьевую базу, только отдельные представители данных родов достаточно исследованы и нашли свое использование как источники биологически активных веществ (БАВ).Цель. Провести хемотаксономическое исследование представителей родов Сrataegus L., Prunus L., Malus Mill., Cerasus Juss.; установить перспективные источники БАВ для получения лекарственных средств.Методы исследования. Хемотаксономическое исследование проводили с использованием метода граф-анализа. Хемомаркерами выступали фенольные соединения и терпеноиды, идентифицированные в генеративных и вегетативных органах представителей родов Сrataegus L., Prunus L., Malus Mill., Cerasus Juss. Идентификацию терпеноидов и органических кислот проводили хромато-масс-спектрометричним методом на хроматографе Agilent Technology 6890N с масс-спектрометрическим детектором 5973N. Флавоноиды и гидроксикоричные  кислоты выявляли хроматографически.Результаты исследования. Установлены химические профили вегетативных и генеративных органов 34 видов рода Сrataegus L., 5 видов рода Prunus L., 7 видов рода Malus Mill., 4 видов рода Cerasus Juss. Установлены перспективные виды боярышников, которые содержат основную группу БАВ рода.Выводы. По результатам хемотаксономического исследования представителей подродов Amygdaloideae и Pyroideae установлены перспективные источники биологически активних веществ (БАВ) видов родов Crataegus L., Prunus L., Malus Mill. и Cerasus Juss. Химический профиль исследуемых родов формируют флавоноиды, терпеноиды и ароматические кислоты. Перспективные виды боярышника были включены в состав фитокомплекса «Кратофит»Світова флора нараховує понад 1000 видів роду Сrataegus L., до підроду Prunus L. належать понад 30 видів, рід Malus Mill. містить 100 видів, до підріду Cerasus Juss. відноситься понад 150 видів. Незважаючи на різноманіття видів та достатню сировинну базу, лише деяки представники цих родів достатньо досліджені та знайшли своє використання як джерела біологічно активних речовин (БАР).Мета. Провести хемотаксономічне дослідження представників родів Сrataegus L., Prunus L., Malus Mill., Cerasus Juss.; встановити перспективні джерела БАР для одержання лікарських засобів.Методи дослідження. Хемотаксономічне дослідження проводили з використанням методу граф-аналізу. Хемомаркерами служили фенольні сполуки та терпеноїди, ідентифіковані у генеративних та вегетативних органах представників родів Сrataegus L., Prunus L., Malus Mill., Cerasus Juss. Ідентифікацію терпеноїдів та органічних кислот проводили хромато-мас-спектрометричним методом на хроматографі Agilent Technology 6890N з мас-спектрометричним детектором 5973N. Флавоноїди та гідроксикоричні кислоти визначали хроматографічно.Результати дослідження. Встановлені хімічні профілі вегетативних та генеративних органів 34 видів роду Сrataegus L., 5 видів роду Prunus L., 7 видів роду Malus Mill., 4 видів роду Cerasus Juss. Встановлені перспективні види глоду, які містять основну групу БАР роду.Висновки. За результатами хемотаксономічного дослідженя представників підродів Amygdaloideae та Pyroideae встановлені перспективні джерела біологічно активних речовин (БАР) видів родів Crataegus L., Prunus L., Malus Mill. та Cerasus Juss. Встановлено, що хімічний профіль досліджених родів формують флавоноїди, терпеноїди та ароматичні кислоти. Перспективні види глоду були введені до складу фітокомплексу «Кратофіт

Intermediate filament accumulation can stabilize microtubules in Caenorhabditis elegans motor neurons

Neural circuits utilize a coordinated cellular machinery to form and eliminate synaptic connections, with the neuronal cytoskeleton playing a prominent role. During larval development of Caenorhabditis elegans, synapses of motor neurons are stereotypically rewired through a process facilitated by dynamic microtubules (MTs). Through a genetic suppressor screen on mutant animals that fail to rewire synapses, and in combination with live imaging and ultrastructural studies, we find that intermediate filaments (IFs) stabilize MTs to prevent synapse rewiring. Genetic ablation of IFs or pharmacological disruption of IF networks restores MT growth and rescues synapse rewiring defects in the mutant animals, indicating that IF accumulation directly alters MT stability. Our work sheds light on the impact of IFs on MT dynamics and axonal transport, which is relevant to the mechanistic understanding of several human motor neuron diseases characterized by IF accumulation in axonal swellings

Dynamic Microtubules Drive Circuit Rewiring in the Absence of Neurite Remodeling

A striking neuronal connectivity change in C. elegans involves the coordinated elimination of existing synapses and formation of synapses at new locations, without altering neuronal morphology. Here, we investigate the tripartite interaction between dynamic microtubules (MTs), kinesin-1, and vesicular cargo during this synapse remodeling. We find that a reduction in the dynamic MT population in motor neuron axons, resulting from genetic interaction between loss of function in the conserved MAPKKK dlk-1 and an α-tubulin mutation, specifically blocks synapse remodeling. Using live imaging and pharmacological modulation of the MT cytoskeleton, we show that dynamic MTs are increased at the onset of remodeling and are critical for new synapse formation. DLK-1 acts during synapse remodeling, and its function involves MT catastrophe factors including kinesin-13/KLP-7 and spastin/SPAS-1. Through a forward genetic screen, we identify gain-of-function mutations in kinesin-1 that can compensate for reduced dynamic MTs to promote synaptic vesicle transport during remodeling. Our data provide in vivo evidence supporting the requirement of dynamic MTs for kinesin-1-dependent axonal transport and shed light on the role of the MT cytoskeleton in facilitating neural circuit plasticity