De-centralizing the Central Dogma: mRNA translation in space and time

Molecular Cell, Journal Year: 2023, Volume and Issue: 83(3), P. 452 - 468

Published: Jan. 19, 2023

As our understanding of the cell interior has grown, we have come to appreciate that most cellular operations are localized, is, they occur at discrete and identifiable locations or domains. These domains contain enzymes, machines, other components necessary carry out regulate these localized operations. Here, review features one such operation: localization translation mRNAs within subcellular compartments observed across types organisms. We describe conceptual advantages "ingredients" mechanisms local translation. focus on nature mRNAs, how travel get this process is regulated. also evaluate current protein synthesis machines (ribosomes) their cadre regulatory elements, factors.

Language: Английский

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Convergent generation of atypical prions in knockin mouse models of genetic prion disease

Journal of Clinical Investigation, Journal Year: 2024, Volume and Issue: 134(15)

Published: July 31, 2024

Most cases of human prion disease arise due to spontaneous misfolding WT or mutant protein, yet recapitulating this event in animal models has proven challenging. It remains unclear whether generation can occur within the mouse lifespan absence protein overexpression and how disease-causing mutations affect strain properties. To address these issues, we generated knockin mice that express misfolding-prone bank vole (BVPrP). While expressing BVPrP (I109 variant) remained free from neurological disease, a subset with (D178N E200K) causing genetic developed progressive illness. Brains spontaneously ill contained disease-specific neuropathological changes as well atypical protease-resistant BVPrP. Moreover, brain extracts D178N- E200K-mutant BVPrP-knockin exhibited seeding activity transmitted Surprisingly, properties prions appeared identical before after transmission, suggesting both guide formation similar strain. These findings imply develop bona fide diseases may share uniform initial mechanism action.

Language: Английский

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Anti-prion drugs do not improve survival in novel knock-in models of inherited prion disease

PLoS Pathogens, Journal Year: 2024, Volume and Issue: 20(4), P. e1012087 - e1012087

Published: April 1, 2024

Prion diseases uniquely manifest in three distinct forms: inherited, sporadic, and infectious. Wild-type prions are responsible for the sporadic infectious versions, while mutant cause inherited variants like fatal familial insomnia (FFI) Creutzfeldt-Jakob disease (fCJD). Although some drugs can prolong prion incubation times up to four-fold rodent models of diseases, no effective treatments FFI fCJD have been found. In this study, we evaluated efficacy various anti-prion on newly-developed knock-in mouse fCJD. These express bank vole protein (PrP) with pathogenic D178N E200K mutations. We applied drug regimens known be highly against wild-type vivo as well a brain-penetrant compound that inhibits PrP Sc propagation vitro . None tested (Anle138b, IND24, Anle138b + cellulose ether, PSCMA) significantly extended disease-free survival or prevented accumulation either model, despite their ability induce strain adaptation prions. Our results show originally developed treat do not necessarily work recombinant sPMCA is reliable platform identifying compounds target This underscores need develop therapies validate screening assays specifically prions, strategies strain-dependent.

Language: Английский

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Therapeutic Trial of anle138b in Mouse Models of Genetic Prion Disease

Journal of Virology, Journal Year: 2023, Volume and Issue: 97(2)

Published: Jan. 18, 2023

There is an urgent need to develop drugs for prion disease, a currently untreatable neurodegenerative disease. In this effort, there debate over which animal models can best support drug development program.

Language: Английский

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Selective Vulnerability to Neurodegenerative Disease: Insights from Cell Type-Specific Translatome Studies

Biology, Journal Year: 2024, Volume and Issue: 13(2), P. 67 - 67

Published: Jan. 23, 2024

Neurodegenerative diseases (NDs) manifest a wide variety of clinical symptoms depending on the affected brain regions. Gaining insights into why certain regions are resistant while others susceptible is vital for advancing therapeutic strategies. While gene expression changes offer clues about disease responses across regions, mixture cell types therein obscures experimental results. In recent years, methods that analyze transcriptomes individual cells (e.g., single-cell RNA sequencing or scRNAseq) have been widely used and provided invaluable specific types. Concurrently, transgene-based techniques dissect type-specific translatomes (CSTs) in model systems, like RiboTag bacTRAP, unique advantages but received less attention. This review juxtaposes merits drawbacks both methodologies, focusing use CSTs understanding conditions amyotrophic lateral sclerosis (ALS), Huntington’s (HD), Alzheimer’s (AD), prion fatal familial insomnia (FFI), genetic Creutzfeldt–Jakob (gCJD), acquired disease. We conclude by discussing emerging trends observed multiple methods.

Language: Английский

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Cerebellar granule neurons induce Cyclin D1 before the onset of motor symptoms in Huntington’s disease mice

Acta Neuropathologica Communications, Journal Year: 2023, Volume and Issue: 11(1)

Published: Jan. 20, 2023

Abstract Although Huntington’s disease (HD) is classically defined by the selective vulnerability of striatal projection neurons, there increasing evidence that cerebellar degeneration modulates clinical symptoms. However, little known about cell type-specific responses neurons in HD. To dissect early mechanisms cerebellum and cerebrum, we analyzed translatomes neuronal types from both regions a new HD mouse model. For this, HdhQ200 knock-in mice were backcrossed with calm 129S4 strain, to constrain experimental noise caused variable hyperactivity C57BL/6 background. Behavioral neuropathological characterization showed these S4-HdhQ200 had very mild behavioral abnormalities starting around 12 months age remained up 18 months. By 9 months, observed abundant Huntingtin-positive intranuclear inclusions (NIIs) striatum cerebellum. The translatome analysis GABAergic cells cerebrum further confirmed changes typical HD-induced pathology. Surprisingly, strongest response 626 differentially expressed genes glutamatergic cerebellum, population consisting primarily granule cells, commonly considered resistant. Our findings suggest vesicular fusion exocytosis, as well differentiation-related pathways are affected neurons. Furthermore, increased expression cyclin D1 ( Ccnd1 ) granular layer upregulated polycomb group complex protein cycle regulators Cbx2, Cbx4 Cbx8 point putative role aberrant regulation disease.

Language: Английский

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Convergent generation of atypical prions in knock-in mouse models of genetic prion disease

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Sept. 27, 2023

Abstract Most cases of human prion disease arise due to spontaneous misfolding wild-type or mutant protein. Though recapitulating conversion in animal models has proven challenging, transgenic mice expressing the misfolding-prone bank vole protein (BVPrP) recreate certain key aspects sporadic and genetic disease. However, it remains unclear whether generation can occur absence over-expression how disease-causing mutations affect strain properties. To address these issues, we generated knock-in physiological levels either BVPrP with isoleucine at codon 109. While remained free from neurological disease, a subset that cause fatal familial insomnia (D178N) Creutzfeldt-Jakob (E200K) developed progressive illness. Brains spontaneously ill contained disease-specific neuropathological changes as well atypical protease-resistant Moreover, brain extracts D178N- E200K-mutant transmitted BVPrP. Surprisingly, properties prions appeared identical both pre- post-transmission, suggesting guide formation highly similar strain. These findings imply develop bona fide causing diseases may share uniform initial mechanism action. Therefore, represent useful tools for studying early stages diseases.

Language: Английский

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Etiology matters: genetic and acquired prion diseases engage different mechanisms at a presymptomatic stage

Neural Regeneration Research, Journal Year: 2023, Volume and Issue: 18(12), P. 2707 - 2708

Published: April 13, 2023

One of the most enigmatic problems in biomedical research surrounds phenomenon that neurodegenerative diseases target specific cell types and brain regions. This is difficult to explain because proteins cause them are widely expressed, often highest resistant mystery further complicated by fact some disease-causing associated with multiple diseases. For example, protein alpha-synuclein forms toxic aggregates including Parkinson’s disease, dementia Lewy bodies, systems atrophy, whereas TDP43 can amyotrophic lateral sclerosis or frontotemporal lobar degeneration (Alegre-Abarrategui et al., 2019; Schweingruber Hedlund, 2022). Alzheimer’s disease from two proteins, amyloid precursor (APP) Tau. Familial mutations APP enzymes process APP. In contrast, Tau not linked but instead frontal temporal dementia, non-mutated also several other (Carroll 2021). Huntington’s one few strictly genetic. It caused an abnormally long polyglutamine tract Huntingtin protein, longer earlier emerges. Remarkably, very tracts a wider distribution affected regions, presenting different clinical signs. The prion (PrP) causes multiple, distinct diseases, collectively called (Jackson, 2014). Prion come three basic forms. infamous form involves infection exogenous source, such as contaminated food medical procedures. infectious agents, prions, consist mostly aggregated PrP (Prusiner, 1982; Bueler 1993; Brandner 1996). Although these acquired main farmed wild animals, they account for only 1% all human A more common humans, accounting about 15% cases, gene encoding PrP. especially fascinating it be separated into subclasses known fatal familial insomnia (FFI), genetic Creutzfeldt-Jakob (gCJD), Gerstmann-Sträussler-Scheinker syndrome, where each has neuropathological changes signs final sporadic, which simply means there no mutation evidence infection. amount, distribution, shapes vary tremendously. Furthermore, hallmarks namely density spongiform concentration infectivity, greatly, barely detectable highly abundant. age at onset varies greatly. easy understand sporadic disease-triggering events may happen any age, present throughout life. mutations, D178N causing FFI E200K gCJD, have ages ranging 12 89 31 92 gCJD (Minikel 2019). Interestingly, when cis M129V substitution. Therefore, mammalian express mutant decades without overt abnormalities this wide variation exist experimental models. To molecular pathways acting researchers employ mouse fact, earliest models were since could established before discovery genes development methods engineering mice. Thus, became studied early days research. Perhaps intensively model developed Rocky Mountain Laboratories (RML) US. was originally derived goat scrapie subsequently passaged tens times through species, until RML strain mouse-adapted established. After passaging, virulent, fastest-killing prions selected. Later, following invention methods, ability study emerged. Mouse based on randomly integrated transgenes dominated field their ease generation high expression levels typically enhance neurological disease. However, overexpression, feature natural animal creates confounders. During synthesis, passes endoplasmic reticulum Golgi apparatus finally resides surface. overexpressed unnatural processing, chaperoning, degradation burden organelles displaces molecules should otherwise occupy those spaces. These issues then confounded added: emerges models, how much effect due overexpression problems, mutation? Another issue spatial patterns differ between transgenic lines random locations genome (Kaczmarczyk Jackson, 2015). pattern variability another confounder: phenotypes emerge sequences, difference differences, sequence differences? over-expression variable avoided knock-in mice variants expressed gene’s native location. Even though avoid serious issues, rarely used important limitations. First, engineer, although CRISPR/Cas-based tools lowering barrier. Second, develop mild Indeed, mice, alleles engineered carry four mildly affected, normal lifespan (Saito accelerate severe enough children (Lin 2001). Nonetheless, phenotype, shortened lifespan. Similarly, bearing single (Jackson 2009, 2013). Importantly, despite having phenotypes, been useful discovering pre-onset stages recent studies, type-specific responses analyzed first employed wild-type 2022), while second expressing equivalent (Bauer Notably, controls same, endogenous location genome, avoiding confounders described above. discover responses, epitope-tagged ribosomes using RiboTag (Figure 1). From homogenates diseased control immunopurified, attached mRNAs, representing genome-wide pool translating mRNAs (translatome), next-generation sequencing methods. There technical differences Illumina platforms, overall similarities, same background, enable comparison results.Figure 1: Capture mRNA RiboTag.Paramagnetic beads labeled antibody HA (hemagglutinin) epitope added (left) made tissues RiboTag-labeled (HA fused ribosomal l22) type interest. antibody::bead complexes capture (middle), purified away undesired (right).In study, identify time points, activity serially measured electroencephalography (EEG) progressed When EEG showed behavioral had yet developed. happened week 18 23-week course considered stage. At 10, identical profiles changes; therefore hemispheres olfactory bulb removed. Analyses translatomes stage revealed massive similar types, even looked healthy. stage, cells responses. glutamatergic neurons, excitatory 38 differentially (DEGs) involving cytoskeleton components regulators cytoskeleton, Arc GABAergic inhibitory 83 DEGs, core circadian rhythm pathway. Surprisingly, parvalbumin large subset neurons previously reported vulnerable many essentially response 3 DEGs. somatostatin (SST) subset, 1 DEG, indicating rhythm-related seen broad population narrow includes neither nor SST subpopulations. astrocytes responded reduced mitochondrial making up 139 lack EEG, timepoint, certain specific, coordinated others all. analyses build previous characterizations Both 21 months leaving unchanged notion around 16 months. chosen translatome analysis 9 months, estimated study. contrast did include astrocytes. cerebellum rest (considered cerebrum) cerebrum separately. Like model, little response, 2 DEGs model. robust 684 153 DEGS, respectively. Some notable included translation ribosome biogenesis, actin Rho GTPases regulate upregulated. Further indicated rapamycin pathway signature both detected data. surprising clinically damage thalamus hippocampus gCJD. regions enriched corresponding samples cerebral relatively 11 strongest 47 28 14 64 Despite total number unrelated metal binding, T synapses. refined approach cerebrum, enhanced detection if comparisons lead conclusion that, stages, surprisingly quite onset, thousands them. examined unfortunate would know converge resemble Such finding support therapy applied targeting ineffective lots need modulated. scenario, therapies needed change course. conclude, beginning perspective alpha-synuclein, viewed comparing significance thinking effective do thus work I like thank members our lab constructive feedback. supported Wallenberg Center Molecular Medicine, Knut Alice foundation, King Gustaf Queen Victoria foundation (to WSJ). Open peer reviewer:Elena De Cecco, University Zurich, Switzerland. Additional file:Open review report 1.P-Reviewer: Cecco E; C-Editors: Zhao M, Liu WJ, Qiu Y; T-Editor: Jia Y

Language: Английский

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Single-cell transcriptomics unveils molecular signatures of neuronal vulnerability in a mouse model of prion disease that overlap with Alzheimer’s disease

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Nov. 23, 2024

Language: Английский

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Therapeutic trial of anle138b in mouse models of genetic prion disease

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Oct. 12, 2022

Abstract Phenotypic screening has yielded small molecule inhibitors of prion replication that are effective in vivo against certain strains but not others. Here we sought to test the anle138b multiple mouse models disease. In mice inoculated with RML strain prions, doubled survival and durably suppressed astrogliosis measured by live animal bioluminescence imaging. knock-in D178N E200K mutations cause genetic disease, however, were unable identify a clear, quantifiable disease endpoint which measure therapeutic efficacy. Among untreated animals, did impact overall survival, remained low out >20 months age. Vacuolization PrP deposition observed some brain regions subset mutant appeared carry weight primary study. We conclude all suited well-powered efficacy studies, care should be taken choosing will support drug development programs.

Language: Английский

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