Search bioRxiv⌕ Search

Biology subjects

Quattrone, A.

Publications and source records attributed to Quattrone, A..

At least 19 recordsLinked to original sources

Centrosome architecture and m6A-dependent gating of p53 surveillanceafter whole-genome doubling

Whole-genome doubling (WGD) generates a tetraploid state that challenges cellular homeostasis and is strongly selected against in TP53-proficient contexts. Although centrosome amplification serves as a structural correlate of genome doubling, how centrosomal features engage and sustain p53 surveillance remains incompletely understood. Here, we develop a genetically encoded MDM2-based fluorescent reporter to monitor Caspase-2 pathway activation in living cells after WGD. Combining pharmacological profiling and genome-wide CRISPR screening, we uncover a multi-layered regulation of p53 responses. We identify PLK1-dependent centriole maturation and subdistal appendage integrity as architectural determinants of PIDDosome-dependent Caspase-2 activation, independent of distal appendage assembly. We show that upon WGD, Caspase-2-mediated cleavage of MDM2 reshapes the p53-MDM2 regulatory loop, enabling sustained p53 signaling. This sustained output depends on the catalytic activity of METTL3 and associated m6A writer proteins. Together, these findings demonstrate that centrosome architecture and epitranscriptomic regulation cooperate to shape p53 surveillance after genome doubling. HighlightsO_LIWhole-genome doubling creates a surveillance state sensed by centrosome cluster architecture. C_LIO_LICaspase-2 activation converts the p53-MDM2 loop from negative to positive feedback. C_LIO_LIm6A methylation establishes competence of the p53 module for sustained output. C_LIO_LIA genetically encoded biosensor enables functional dissection of this circuit. C_LI

cell biology↗

Unveiling Oligodendrocyte-Lineage Differentiation in the Glioblastoma Infiltrative Zone Through Spatial Transcriptomics

IDH-wildtype glioblastoma (GBM) is the most aggressive primary brain tumor, characterized by limited therapeutic options and inevitable recurrence. This recurrence is driven by the highly infiltrative behavior of GBM cells, which prevents complete resection. Here, we performed spatially resolved transcriptomic profiling of four surgically defined GBM regions to characterize the infiltrative tumor compartment. Across multiple datasets and profiling approaches, the infiltrative zone showed reduced cellular heterogeneity compared with the tumor core. By comparison with an integrated reference of single-cell RNA sequencing data, we revealed that this reduction reflects a preferential differentiation of infiltrative GBM cells toward an oligodendrocyte-like lineage, accompanied by attenuated inflammatory signaling. In contrast, necrotic and proliferative regions display pronounced astrocyte-like and mesenchymal-like programs. Combined immunohistochemistry and fluorescence in situ hybridization confirmed the enrichment of oligodendrocyte-like tumor cells in the infiltrative area. Together, these findings identify the oligodendrocyte-like state as a defining feature and potential therapeutic vulnerability of infiltrative GBM driving brain invasion and relapse.

cancer biology↗

Non-neuronal, TGF-β- extracellular matrix restructuring promotes neurodegeneration in a PSP-Richardson syndrome model

Progressive supranuclear palsy-Richardson syndrome (PSP-RS) is a rapidly progressive tauopathy lacking effective therapies. Although tau aggregation is a defining feature, the initiating mechanisms remain elusive. Here we used patient-derived induced pluripotent stem cell midbrain organoids, integrating single-cell transcriptomics, bulk RNA profiling, and quantitative proteomics, to dissect early pathogenic events. We identified vascular leptomeningeal-like cells (VLMCs) as the first altered population, exhibiting TGF-{beta}-driven extracellular matrix (ECM) remodeling enriched in collagens, integrins, and TGFBI. The resulting pathological ECM increased stiffness, induced integrin clustering, and activated RhoA-ROCK-mediated cytoskeletal disorganization. These changes sustained PI3K-AKT and MAPK-ERK signaling, suppressed PP2A, hyperactivated mTOR, and impaired autophagy, culminating in tau hyperphosphorylation and mislocalization. Pharmacological inhibition of TGF-{beta}, AKT, ERK, or mTORC1 restored autophagic flux, reduced tau burden, and rescued neuronal architecture. Our findings establish non-neuronal, matrix-producing niche cells as upstream drivers of tauopathy and reveal TGF-{beta}-mediated ECM restructuring as a mechanochemical trigger of neurodegeneration, opening multiple therapeutic avenues for PSP-RS and related tauopathies.

neuroscience↗

Model-independent reorganization of translation in TDP-43 Amyotrophic Lateral Sclerosis

The RNA-binding protein TDP-43 is a major contributor and a pathological hallmark of Amyotrophic Lateral Sclerosis (ALS), yet how TDP-43 dysregulation mechanistically alters protein synthesis across neuronal compartments and disease models remains unclear. Here, we dissected TDP-43-driven translational alterations in both in vitro and in vivo TDP-43 models of ALS. Through ribosome and polysome profiling, computational, and biochemical analyses, we observed robust TDP-43-associated translational remodelling at cellular and subcellular resolution. Our findings reveal a conserved mechanism across models, characterized by enhanced ribosome recruitment on polysomes, elongation impairment, axonal downregulation and instability of TDP-43 target mRNAs and redistribution toward non-target transcripts. Notably, TDP-43 dysregulation alters ribosome dynamics and selectively impairs translation of TDP-43 target mRNAs, whilst favouring the translation of other transcripts. This process reflects a compensatory but maladaptive response to TDP-43-induced mRNA destabilization. Together, these data demonstrate that alterations in TDP-43 disrupts neuronal proteostasis through ribosome reorganization and loss of mRNA homeostasis, providing a unifying mechanistic framework for translational imbalance in ALS and revealing early molecular events that may underlie motor neuron vulnerability.

molecular biology↗

The three YTHDF paralogs and VIRMA are the major tumor drivers among the m6A core genes in a pan-cancer analysis

N6-methyladenosine (m6A) is the most abundant internal modification in mRNAs. Despite accumulating evidence for the profound impact of m6A on cancer biology, there are conflicting reports that alterations in genes encoding the m6A machinery proteins can either promote or suppress cancer, even in the same tumor type. Using data from The Cancer Genome Atlas, we performed a pan-cancer investigation of 15 m6A core factors in nearly 10,000 samples from 31 tumor types to reveal underlying cross-tumor patterns. Altered expression, largely driven by copy number variations at the chromosome arm level, results in the most common mode of dysregulation of these factors. YTHDF1, YTHDF2, YTHDF3, and VIRMA are the most frequently altered factors and the only ones to be uniquely altered when tumors are grouped according to the expression pattern of the m6A factors. These genes are also the only ones with coherent, pan-cancer predictive power for progression-free survival. On the contrary, METTL3, the most intensively studied m6A factor as a cancer target, shows much lower levels of alteration and no predictive power for patient survival. Therefore, we propose the non-enzymatic YTHDF and VIRMA genes as preferred subjects to dissect the role of m6A in cancer and as priority cancer targets. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/598899v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1e39eeborg.highwire.dtl.DTLVardef@d6628dorg.highwire.dtl.DTLVardef@e048a6org.highwire.dtl.DTLVardef@c19812_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Mosaic midbrain organoids: a new tool to study Progressive Supranuclear Palsy and advancing clinical neurology research

Progressive supranuclear palsy (PSP) is a severe neurodegenerative disease pathologically characterized by intracellular tangles of hyperphosphorylated tau protein, widely distributed across the neocortex, basal ganglia, and midbrain. Developing effective drugs for PSP presents challenges due to its complex underpinning mechanism and the absence of robust human models that accurately recapitulate biochemical and pathological features of the disease phenotype. Brain organoids have recently emerged as a three-dimensional tissue culture platform to study brain development and pathology. Here, we present a novel induced pluripotent stem cell (iPSC)-derived mosaic midbrain organoid (mMOs) system from four patients with progressive supranuclear palsy-Richardson syndrome (PSP-RS), aimed at reproducing key molecular disease features while reducing variability across organoids derived from different iPSC donors. The PSP-RS 3D model exhibited accumulation of hyperphosphorylated tau protein, predominance of 4R-tau, increased GFAP-positive cells, and PSP-associated histological alterations compared to organoids derived from healthy donors. Pathologically, diseased mMOs showed typical neurofibrillary tangles and tufted-shaped astrocytes, and poorly branched processes of Tyrosine Hydroxylase-immunoreactive cells with thin terminal branches. Our results suggest that mMOs represent a valuable experimental model for PSP research and hold great promise for future identification of new therapeutic targets for progressive supranuclear palsy. O_FIG O_LINKSMALLFIG WIDTH=185 HEIGHT=200 SRC="FIGDIR/small/597136v1_unfig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@8b2942org.highwire.dtl.DTLVardef@41e3baorg.highwire.dtl.DTLVardef@1cddaeeorg.highwire.dtl.DTLVardef@1e0716c_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

CD81-guided heterologous EVs present heterogeneous interactions with breast cancer cells

Extracellular vesicles (EVs) are cell-secreted particles conceived as natural vehicles for intercellular communication. The intrinsic biocompatibility, stability in biofluids, and heterogeneous molecular cargo of EVs promise advancements in targeted therapy applications. However, predicting cell-targeting spectrum and cargo delivery are fundamental challenges for exploiting EVs or hybrid formulations. In this work, we combined cell-based and biochemical approaches to understand if secreted EVs show predictable EV-cell interactions and consequent cargo delivery. We exploited the tetraspanin CD81 to encode full-length recombinant proteins with a C-terminal GFP reporter encompassing or not Trastuzumab light chains targeting the HER2 receptor. These fusion proteins participated in vesicular trafficking dynamics and accumulated on secreted EVs when transiently over-expressed in HEK293T cells. Despite the presence of GFP, secreted EV populations retained a HER2 receptor-binding capacity and were used in EV-cell interaction assays. In time-frames where the global GFP spot distribution did not change between HER2-positive (SK-BR-3) or -negative (MDA-MB-231) breast cancer cell lines, the HER2 manipulation in isogenic cells remarkably affected the tropism of heterologous EVs. In this line, secreted doxorubicin-EVs, which showed improved efficacy compared to the free drug, had a reduced cell-killing activity on SK-BR-3 with a knocked-out HER2 receptor. Interestingly, the fusion protein-corresponding transcripts also present as full-length mRNAs in recombinant EVs could reach orthotopic breast tumors in JIMT-1-xenografted mice, as detected by ddPCR in tissue biopsies, improving our sensitivity in detecting bioavailable cargoes. These data show multiple mechanisms underlying EV-cell interactions and prioritize the profiling of surfaceomes for better comprehension of cell engagement and design new generations of EV-based nanovehicles.

molecular biology↗

Zea mays genotype influences microbial and viral rhizobiome community structure

Plant genotype is recognized to contribute to variations in microbial community structure in the rhizosphere, soil adherent to roots. However, the extent to which the viral community varies has remained poorly understood and has the potential to contribute to variation in soil microbial communities. Here we cultivated replicates of two different genotypes of Zea mays parviglumis and Z. mays genotype B73 in a greenhouse and harvested the rhizobiome (rhizoplane and rhizosphere) to identify the abundance of cells and viruses as well as apply 16S rRNA gene amplicon sequencing and genome resolved metagenomics to identify the rhizobiome microbial and viral community. Our results demonstrate that viruses exceeded microbial abundance in the rhizobiome of parviglumis and B73 with a significant variation in both, the microbial and viral community between the two genotypes. Of the viral contigs identified only 4.5% (n =7) of total viral contigs were shared between the two genotypes, demonstrating that plants even at the level of genotype can significantly alter the surrounding soil viral community. An auxiliary metabolic gene associated with glycoside hydrolase (GH5) degradation was identified in one viral metagenome-assembled genome (vMAG) identified in the B73 rhizobiome infecting Propionibacteriaceae (Actinobacteriota) further demonstrating the viral contribution in metabolic potential for carbohydrate degradation and carbon cycling in the rhizosphere. This variation demonstrates the potential of plant genotype to contribute to microbial and viral heterogeneity in soil systems and harbor genes capable of contributing to carbon cycling in the rhizosphere.

microbiology↗

Insights from the IronTract challenge: optimal methods for mapping brain pathways from multi-shell diffusion MRI

Limitations in the accuracy of brain pathways reconstructed by diffusion MRI (dMRI) tractography have received considerable attention. While the technical advances spearheaded by the Human Connectome Project (HCP) led to significant improvements in dMRI data quality, it remains unclear how these data should be analyzed to maximize tractography accuracy. Over a period of two years, we have engaged the dMRI community in the IronTract Challenge, which aims to answer this question by leveraging a unique dataset. Macaque brains that have received both tracer injections and ex vivo dMRI at high spatial and angular resolution allow a comprehensive, quantitative assessment of tractography accuracy on state-of-the-art dMRI acquisition schemes. We find that, when analysis methods are carefully optimized, the HCP scheme can achieve similar accuracy as a more time-consuming, Cartesian-grid scheme. Importantly, we show that simple pre- and post-processing strategies can improve the accuracy and robustness of many tractography methods. Finally, we find that fiber configurations that go beyond crossing (e.g., fanning, branching) are the most challenging for tractography. The IronTract Challenge remains open and we hope that it can serve as a valuable validation tool for both users and developers of dMRI analysis methods.

neuroscience↗

One-shot analysis of translated mammalian lncRNAs with AHARIBO

A vast portion of the mammalian genome is transcribed as long non-coding RNAs (lncRNAs) acting in the cytoplasm with largely unknown functions. Surprisingly, lncRNAs have been shown to interact with ribosomes, encode uncharacterized proteins, or act as ribosome sponges. These functions still remain mostly undetected and understudied owing to the lack of efficient tools for genome-wide simultaneous identification of ribosome-associated lncRNAs and peptide-producing lncRNAs. Here we present AHARIBO, a method for the detection of lncRNAs either untranslated, but associated with ribosomes, or encoding small peptides. Using AHARIBO in mouse embryonic stem cells during neuronal differentiation, we isolated ribosome-protected RNA fragments, translated RNAs and corresponding de novo synthesized polypeptides. Besides identifying mRNAs under active translation and associated ribosomes, we found and distinguished lncRNAs acting as ribosome sponges or encoding micropeptides, laying the ground for a better functional understanding of hundreds lncRNAs.

cell biology↗

The m6A reader Ythdf restricts axonal growth in Drosophila through target selection modulation of the Fragile X mental retardation protein

N6-methyladenosine (m6A) regulates a variety of physiological processes through modulation of RNA metabolism. The modification is particularly enriched in the nervous system of several species, and its dysregulation has been associated with neurodevelopmental defects and neural dysfunctions. In Drosophila, loss of m6A alters fly behavior albeit the underlying mechanism and the role of m6A during nervous system development have remained elusive. Here we find that impairment of the m6A pathway leads to axonal overgrowth and misguidance at larval neuromuscular junctions as well as in the adult mushroom bodies. We identify Ythdf as the main m6A reader in the nervous system being required for limiting axonal growth. Mechanistically, we show that Ythdf directly interacts with Fragile X mental retardation protein to inhibit the translation of key transcripts involved in axonal growth regulation. Altogether, this study demonstrates that the m6A pathway controls development of the nervous system by modulating Fmr1 target selection.

molecular biology↗

p53-induced apoptosis is specified by a translation program regulated by PCBP2 and DHX30.

Activation of p53 by the small molecule Nutlin can result in a combination of cell cycle arrest and apoptosis. The relative strength of these events is difficult to predict by classical gene expression analysis, leaving uncertainty as to the therapeutic benefits of Nutlin. Here, we report a new translational control mechanism shaping p53-dependent apoptosis. Using polysome profiling, we establish Nutlin-induced apoptosis to be associated with the enhanced translation of mRNAs carrying multiple copies of a newly identified 3UTR CG-rich motif mediating p53-dependent death (CGPD-motif). We identified PCBP2 and DHX30 as CGPD-motif interactors. We found that in cells undergoing persistent cell cycle arrest in response to Nutlin, CGPD-motif mRNAs are repressed by the PCBP2-dependent binding of DHX30 to the motif. Thus, upon DHX30 depletion in these cells, the translation of CGPD-motif mRNAs is increased, and the response to Nutlin shifts towards apoptosis. Instead, DHX30 inducible overexpression in SJSA1 cells, that undergo Nutlin-induced apoptosis, leads to decreased translation of CGPD-motif mRNAs. Overall, this work establishes the role of PCBP2-DHX30 in controlling the translation of CGPD-motif mRNAs and thus provide a new mechanism to modulate the induction of p53-dependent apoptosis.

molecular biology↗

SMN-primed ribosomes modulate the translation of transcripts related to Spinal Muscular Atrophy

The contribution of ribosome heterogeneity and ribosome-associated factors to the molecular control of proteomes in health and disease remains enigmatic. We demonstrate that Survival Motor Neuron (SMN) protein, loss of which causes the neuromuscular disease spinal muscular atrophy (SMA), binds to ribosomes and that this interaction is tissue-dependent. SMN-primed ribosomes are positioned within the first five codons of a set of mRNAs which are enriched in IRES-like sequences in the 5UTR and rare codons at the beginning of their coding sequence. Loss of SMN at early-stages of SMA induces translational defects in vivo, characterized by ribosome depletion in rare codons at the third and fifth position of the coding sequence. These positional defects cause ribosome depletion from mRNAs bound by SMN-primed ribosomes and translational impairment of proteins involved in motor neuron function and stability, including acetylcholinesterase. Thus, SMN plays a crucial role in the regulation of ribosome fluxes along mRNAs which encode proteins relevant to SMA pathogenesis.

neuroscience↗

Hypomorphic mutation of the mouse Huntingtons disease gene orthologue

Rare individuals with hypomorphic inactivating mutations in the Huntingtons Disease (HD) gene (HTT), identified by CAG repeat expansion in the eponymous neurodegenerative disorder, exhibit variable abnormalities that imply HTT essential roles during organ development. Here we report phenotypes produced when increasingly severe hypomorphic mutations in Htt, the murine HTT orthologue (in HdhneoQ20, HdhneoQ50, HdhneoQ111 mice), were placed over a null allele (Hdhex4/5). The most severe hypomorphic allele failed to rescue null lethality at gastrulation, while the intermediate alleles yielded perinatal lethality and a variety of fetal abnormalities affecting body size, skin, skeletal and ear formation, and transient defects in hematopoiesis. Comparative molecular analysis of wild-type and Htt-null retinoic acid-differentiated cells revealed gene network dysregulation associated with organ development and proposed polycomb repressive complexes and miRNAs as molecular mediators. Together these findings demonstrate that the HD gene acts both pre- and post-gastrulation and possibly suggest pleiotropic consequences of HTT-lowering therapeutic strategies.\n\nAuthor SummaryThe HTT gene product mutated in Huntingtons Disease (HD) has essential roles during normal organism development, however, still not fully predictable are the functional consequences of its partial inactivation. Our genetic study provides a comprehensive effects description of progressively stronger suppression of Htt gene, the murine HTT counterpart. The most severe Htt reduction leads to embryo lethality, while intermediate Htt dosages yield a variety of developmental abnormalities affecting body size, skin, skeletal and ear formation, and hematopoiesis. Complementing molecular analysis in differentiating cells depleted of a functional Htt gene further elucidates genes networks dysregulated during organ development and proposes chromatin regulators and short non-coding RNAs as key molecular mediators. Together these findings demonstrate that the HD gene acts both at early and later stages of development, thus possibly suggesting long-term consequences associated to the newest HD therapeutic strategies aimed at lowering the HTT gene product.

genetics↗

An homeotic post-transcriptional network controlled by the RNA-binding protein RBMX

Post-transcriptional regulation (PTR) of gene expression is a powerful determinant of protein levels and cellular phenotypes. The 5 and 3 untranslated regions of the mRNA (UTRs) mediate this role through sequence and secondary structure elements bound by RNA-binding proteins (RBPs) and noncoding RNAs. While functional regions in the 3UTRs have been extensively studied, the 5UTRs are still relatively uncharacterized. To fill this gap, here we used a computational approach based on phylogenetic conservation to identify hyper-conserved elements in human 5UTRs (5HCEs). Our assumption, supported by the recovery of functionally characterized elements, was that 5HCEs would represent evolutionarily stable and hence important PTR sites.\n\nWe identified over 5000 short, clustered 5HCEs occurring in approximately 10% of human protein-coding genes. Among these, homeotic genes were highly enriched. Indeed, 52 of the 258 characterized homeotic genes contained at least one 5HCE, including members of all four Hox clusters and several other families. Homeotic genes are essential transcriptional regulators. They drive body plan and neuromuscular development, and the role of PTR in their expression is mostly unknown. By integrating computational and experimental approaches we then identified the RBMX RNA-binding protein as the initiator of a post-transcriptional cascade regulating many such homeotic genes. RBMX is known to control its targets by modulating transcript abundance and alternative splicing. Adding to that, we observed translational control as a novel mode of regulation by this RBP.\n\nThis work thus establishes RBMX as a versatile master controller of homeotic genes and of the developmental processes they drive.

genomics↗

Small effect size leads to reproducibility failure in resting-state fMRI studies

Thousands of papers using resting-state functional magnetic resonance imaging (RS-fMRI) have been published on brain disorders. Results in each paper may have survived correction for multiple comparison. However, since there have been no robust results from large scale meta-analysis, we do not know how many of published results are truly positives. The present meta-analytic work included 60 original studies, with 57 studies (4 datasets, 2266 participants) that used a between-group design and 3 studies (1 dataset, 107 participants) that employed a within-group design. To evaluate the effect size of brain disorders, a very large neuroimaging dataset ranging from neurological to psychiatric isorders together with healthy individuals have been analyzed. Parkinsons disease off levodopa (PD-off) included 687 participants from 15 studies. PD on levodopa (PD-on) included 261 participants from 9 studies. Autism spectrum disorder (ASD) included 958 participants from 27 studies. The meta-analyses of a metric named amplitude of low frequency fluctuation (ALFF) showed that the effect size (Hedges g) was 0.19 - 0.39 for the 4 datasets using between-group design and 0.46 for the dataset using within-group design. The effect size of PD-off, PD-on and ASD were 0.23, 0.39, and 0.19, respectively. Using the meta-analysis results as the robust results, the between-group design results of each study showed high false negative rates (median 99%), high false discovery rates (median 86%), and low accuracy (median 1%), regardless of whether stringent or liberal multiple comparison correction was used. The findings were similar for 4 RS-fMRI metrics including ALFF, regional homogeneity, and degree centrality, as well as for another widely used RS-fMRI metric namely seed-based functional connectivity. These observations suggest that multiple comparison correction does not control for false discoveries across multiple studies when the effect sizes are relatively small. Meta-analysis on un-thresholded t-maps is critical for the recovery of ground truth. We recommend that to achieve high reproducibility through meta-analysis, the neuroimaging research field should share raw data or, at minimum, provide un-thresholded statistical images.

neuroscience↗

Intracellular FMRpolyG-HSP70 complex: Possible use as biochemical marker of Fragile X Tremor Ataxia Syndrome

INTRODUCTION INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION Author Contributions AKNOWLEDGMENTS CONFLICT OF INTEREST References Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects about 25% of carriers of non-coding CGG-repeat expansions (55-200 repeats) in the premutation range within the fragile X gene (FMR1). Main clinical features include intention tremor, cerebellar ataxia, and Parkinsonism [1]. Recently, great emphasis on the pathogenetic role of toxic aggregates, produced by a RAN translation process on the 5 expanded CGG region, has been given [2,3]. These aggregates contain a small protein with a polyglycin stretch, (FMRpolyG), a ...

cell biology↗

HuD is a neural enhancer of global translation acting on mTORC1-responsive genes and sponged by the Y3 small non-coding RNA

The RNA-binding protein HuD promotes neurogenesis and favors recovery from peripheral axon injury. HuD interacts with many mRNAs, altering both stability and translation efficiency. UV-crosslinking and analysis of cDNA (CRAC) generated a nucleotide resolution map of the HuD RNA interactome in motor neuron-like cells. HuD target sites were identified in 1304 mRNAs, predominantly in the 3UTR, with enrichment for genes involved in protein synthesis and axonogenesis. HuD bound many mRNAs encoding mTORC1-responsive ribosomal proteins and translation factors. Altered HuD expression correlated with the translational efficiency of these mRNAs and overall protein synthesis, in a mTORC1-independent fashion. The predominant HuD target was the abundant, small non-coding RNA Y3, which represented 70% of HuD interaction signal. Y3 functions as a molecular sponge for HuD, dynamically limiting its activity. These findings uncover an alternative route to the mTORC1 pathway for translational control in motor neurons that is tunable by a small non-coding RNA.\n\nGraphical abstract\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC=\"FIGDIR/small/205658_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (69K):\norg.highwire.dtl.DTLVardef@17b2d21org.highwire.dtl.DTLVardef@1cfdc8borg.highwire.dtl.DTLVardef@1984f88org.highwire.dtl.DTLVardef@8da1ee_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗