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Olender, T.

Publications and source records attributed to Olender, T..

At least 19 recordsLinked to original sources

A massively parallel reporter screen defines the syntax of SECReTE, a secretion-enhancing cis regulatory targeting element, in mammalian cells

Messenger RNA (mRNA) localization to specific subcellular regions is crucial for proper protein translation and localization. Potential means to localize mRNAs include cis-acting or structural motifs embedded within the sequence. We previously identified a secretion-enhancing cis regulatory targeting element (SECReTE) enriched in mRNAs encoding secreted proteins from prokaryotes, eukaryotes, and viruses, found to enhance both protein synthesis and secretion by localizing mRNAs to the endoplasmic reticulum (ER) membrane. Defined as at least 10 consecutive NNY triplets (where N is any nucleotide and Y is a pyrimidine), this highly degenerate motif can be specified by approximately ~10^15 different sequence combinations. Yet, some combinations may prove more efficient than others in regulating mRNA localization and protein secretion. To better understand SECReTE syntax and to identify robust combinations, we designed and synthesized a library of ~5 x 10^4 variants and inserted them into the 3' untranslated region (3'UTR) of two reporter genes, green fluorescent protein (GFP) and immunoglobulin light chain. We expressed each variant in Chinese hamster ovary cells and assayed their activity using parallel assays to measure the effect of each variant upon mRNA partitioning between the ER and cytoplasm, and protein secretion. Our results reveal that ER-associated mRNAs are enriched with SECReTE elements of a defined syntax. Notably, RRY repeats (where R is purine) were superior to NNY repeats. Variants conferring a high mRNA ER localization score consistently enhanced protein secretion, confirming the mechanistic relationship between mRNA targeting to the ER and secretion efficiency. The correlation between variant performances across both reporters suggests a shared regulatory mechanism. Additional analysis identified a novel secretion-promoting cis element, called "split NNS" (where S is G or C). This work refines the syntactic definition of mRNA localization motifs that regulate protein secretion in both natural and heterologous expression systems.

cell biology↗

RTTN moonlights beyond the centrosome to control ribosome biogenesis and tRNA modification in human brain organoids

RTTN (rotatin) is a centrosomal protein mutated in severe malformations of cortical development, yet how its dysfunction disrupts human corticogenesis has remained unclear. Here, we show that RTTN has an unrecognized function at the core of the translation machinery. Using human telencephalic and hippocampal organoids carrying distinct RTTN alleles, together with single-cell and bulk transcriptomics, polysome profiling, and tRNA pseudouridine sequencing, we find that RTTN is enriched in cycling first-trimester neural progenitors and physically associates with ribosome-biogenesis and RNA-processing factors. RTTN mutations impair rRNA biogenesis and polysome assembly, reduce cytoplasmic ribosome density and nascent protein synthesis, and remodel the tRNA pseudouridylation landscape through both a PUS7L-dependent variable-arm signature and a broader RTTN-specific defect. These translational deficits are accompanied by prolonged mitosis, reduced entry into S-phase, and impaired interkinetic nuclear migration in mutant progenitors. Our findings redefine RTTN as a regulator of ribosome homeostasis and mRNA translation and implicate defective translational capacity as a driver of RTTN-associated microcephaly. Graphical AbstractRTTN sustains ribosome and tRNA homeostasis in human neural progenitors; its mutation disrupts mRNA translation, stalling progenitor proliferation and interkinetic nuclear migration, and driving cortical malformation and growth failure. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/744412v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@16124aaorg.highwire.dtl.DTLVardef@ae23f7org.highwire.dtl.DTLVardef@bb588forg.highwire.dtl.DTLVardef@1b35028_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

A low-dimensional transcriptional code enables decoding of BMP/TGFβ signaling from single-cell transcriptomes

Cells interpret complex extracellular environments through signaling pathways that compress diverse ligand inputs into a limited set of intracellular mediators. How this information is encoded in transcriptional responses, and whether it can be decoded to infer the original signaling environment, remains unclear. Here, we systematically map BMP/TGF{beta} transcriptional responses using single-cell RNA sequencing across 48 ligand-concentration conditions, generating a multi-ligand dose-response atlas. We find that, for each ligand, transcriptional responses collapse onto a one-dimensional, highly coordinated program in which concentration modulates response amplitude without altering gene identity. Across ligands, we find a small number of distinct, ligand-dependent transcriptional programs. We leverage this structured encoding to define a quantitative perception score that captures pathway activity at single-cell resolution. Finally, we train a machine learning model to decode extracellular ligand concentrations from single-cell transcriptomes. The model further generalizes to in vivo intestinal epithelium, where it reconstructs the spatial BMP gradient profile. Together, these results reveal a low-dimensional transcriptional code in BMP/TGF{beta} signaling that constrains cellular responses and enables quantitative inference of extracellular signaling environments from gene expression.

systems biology↗

Lysosome-Related Organelles Orchestrate Guanine Crystal Formation in Pigment Cells

Iridosomes, the guanine crystal-forming organelles of pigment-producing iridophores, are among the most versatile, visually striking yet mechanistically uncharacterized organelles in vertebrate biology. Lysosome-related organelles (LROs) support cell type-specific functions by adapting endolysosomal pathways for specialized roles. Here, we show that iridosomes represent a previously unrecognized subtype of LROs. Using transcriptomic profiling of zebrafish iridophores, CRISPR-Cas9-mediated gene disruption, and cryogenic transmission electron microscopy, we define the molecular program underlying iridosome biogenesis. Iridosomes have evolved unique adaptations for crystal growth while retaining core features of other LROs. Key regulators, including RAB32a, AP3M2, and HPS5, are essential for crystal formation, with gene knockouts causing reduced crystal number, altered morphology, and distinct maturation defects. We further identify hallmark LRO features in iridosomes, including intraluminal vesicles and pH-regulated developmental transitions. Cross-species transcriptomic analysis confirms that iridosomes share an LRO signature across vertebrates, including teleost fish and reptiles, suggesting ancient evolutionary origins. These findings establish iridosomes as crystalline LROs and as a model for investigating how cells construct structurally specialized organelles through coordinated trafficking, acid-base regulation, and crystallization, with implications for LRO evolution and human disease.

developmental biology↗

Neural Progenitors as a Novel Pathogenic Mechanism in Microcephaly

Despite their significance, the genetic and molecular bases of neurodevelopmental disorders remain poorly understood. In this study, using human brain organoids and mouse models, we show that loss of NDE1, a gene closely associated with microcephaly, disrupts progenitor identity, prolongs mitosis, and alters regional patterning in the forebrain. NDE1 knockout leads to a caudal identity shift of neural progenitor cells in the organoids and mouse brains, coinciding with aberrant ERK signaling. Notably, downstream activation of the ERK pathway restored rostral PAX6 expression in human brain organoids. Parallel analyses of Nde1 knockout mice confirmed disrupted regional patterning of the forebrain. Together, our data establish NDE1 as a critical regulator of early human brain regionalization and elucidate molecular mechanisms underlying the structural abnormalities observed in NDE1-associated microcephaly.

developmental biology↗

Specialized Molecular Pathways Drive the Formation of Light-Scattering Assemblies in Leucophores

Pigmentation plays a vital role in the survival of organisms, supporting functions such as camouflage, communication, and mate attraction. In vertebrates, these functions are mediated by specialized pigment cells known as chromatophores of which, uric acid crystal-forming leucophores remain the least understood, with little known about their molecular mechanisms. A key question in pigment cell biology is whether different crystal chemistries require distinct molecular pathways, or whether similar cellular processes drive the formation of diverse crystals. This study was designed to unravel the uncharacterized process of uric acid crystallization in leucophores and compare them to guanine crystal formation in iridophores and pterin formation in xanthophores. The results of our transcriptomic, ultrastructural, and metabolomic analyses, demonstrate that leucophores share molecular pathways with iridophores, particularly those connected to organelle organization and purine metabolism, but express discrete genes involved in uric acid biosynthesis and storage. Additionally, leucophores share intracellular trafficking and pterin biosynthesis genes with xanthophores, suggesting universally conserved processes. Ultrastructural studies reveal star-like fibrous structures in leucosomes, which likely serve as scaffolds for unique one-dimensional uric acid assemblies that radiate from the core and act as efficient light scatterers. These findings provide new insights into leucophore cell biology and the specialized mechanisms driving molecular crystalline assembly, and reveal that while some cellular processes are conserved, the specific chemistry of each crystal type drives the evolution of distinct molecular pathways.

cell biology↗

The RNA-binding protein PRRC2B preserves 5' TOP mRNA during starvation to maintain ribosome biogenesis during nutrient recovery

PRRC2B is an intrinsically disordered RNA-binding protein that is part of the cells translation machinery. Here we show that PRRC2B has two alternatively spliced mRNA transcripts producing major long and minor short isoforms. Mass spectrometry-based interaction studies indicated that both isoforms associate with the 40S ribosomal subunit and translation initiation factors. Importantly, the long isoform also interacted with additional RNA-binding proteins through its unique Arg/Gly-rich region. Among these is LARP1, a regulator of 5 terminal oligopyrimidine (TOP) mRNAs under conditions of mTOR inhibition. We discovered that like LARP1, PRRC2B is necessary for preservation of 5 TOP mRNA levels, particularly those encoding ribosomal proteins, during amino acid starvation. In its absence, the rapid de novo translation of ribosomal proteins that takes place upon nutrient recovery is impeded. Overall, our study elucidates a newly discovered function for PRRC2B as an RNA-binding protein that regulates ribosomal biogenesis upon metabolic shift, in addition to its established function in initiating translation of specific mRNA targets.

molecular biology↗

A new targeting motif for endoplasmic reticulum surface proteins

The Endoplasmic Reticulum (ER) is the entry site to the secretory pathway, serving as the targeting destination for [~]30% of the proteome. The mechanisms for targeting soluble or integral membrane secretory pathway proteins are well-studied. However, it is currently unknown how the tens of ER surface proteins (SuPs), central for organelle function, reach the outer leaflet of the membrane. It was previously shown that an amphipathic helix (AH) from the Brome mosaic virus protein 1a, is both necessary and sufficient for targeting to the ER surface in bakers yeast. We therefore utilized this helix as a model substrate and performed a high-content screen to uncover factors that affect SuP targeting. Our results suggest a role for membrane lipid composition in targeting specificity. To see if the presence of an AH is a more general mechanism for SuP targeting, we searched for their presence within SuPs of both yeast and humans. Five endogenous yeast SuPs contained AHs, and of these four were sufficient for ER localization. Moreover, the presence of an AH was conserved to human SuP orthologs. By altering helix features we determine the parameters that affect this new targeting motif. Hence our work demonstrates how specific properties of AHs encode affinity for the ER membrane. More globally, understanding how SuPs are targeted correctly takes us a step forward in determining the underlying mechanisms of cellular localization and secretory pathway functions. The authors declare that they have no conflict of interest.

cell biology↗

Altered Extracellular Matrix Structure and Elevated Stiffness in a Brain Organoid Model for Disease

The viscoelasticity of tissues impacts their shape, as well as the growth and differentiation of their cells. Nevertheless, little is known about changes in viscoelastic properties during brain malformations. Lissencephaly is a severe malformation of cortical development caused by LIS1 mutations, which results in a lack of cortical convolutions. Here, we show that human-derived brain organoids with LIS1 mutation are stiffer than control ones at multiple developmental times. This stiffening is accompanied by abnormal ECM expression and organization, as well as elevated water content, as measured by diffusion-weighted MRI. Proteolytic cleavage of ECM components by short-term treatment with the catalytic subunit of MMP9 reduced the stiffening and water diffusion levels of mutated organoids to control levels. Finally, based on the molecular and rheological properties obtained, we generated a computational microstructure mechanical model that can successfully predict mechanical changes that follow differential ECM localization and integrity in the developing brain. Overall, our study reveals that LIS1 is essential for the expression and organization of ECM proteins during brain development, and its mutation leads to a substantial viscoelastic change. To our knowledge, this is the first study to elucidate how tissue mechanics change in disease states using human brain organoids.

developmental biology↗

Loss of EIF4G2 Mediates Aggressiveness in Distinct Human Endometrial Cancer Subpopulations with Poorer Survival Outcome in Patients

The non-canonical translation initiation factor EIF4G2 plays essential roles in embryonic development and differentiation, and contributes to the cellular stress response via translation of selective mRNA cohorts. Currently there is limited and conflicting information regarding the potential involvement of EIF4G2 in cancer development and progression. Endometrial cancer (EC) is the most pervasive gynecological cancer in the developed world, with increasing incidence every year. High grade ECs are largely refractory to conventional treatments, presenting poor survival rates and lacking suitable prognostic markers. Here we assayed a cohort of 280 EC patients across different types, grades, and stages, and found that low EIF4G2 expression highly correlated with poor overall and recurrence free survival in Grade 2 EC patients, monitored over a period of up to 12 years. To establish a causative connection between low EIF4G2 expression and cancer progression, we analyzed in parallel two independent human EC cell lines and demonstrated that stable EIF4G2 knock-down resulted in increased resistance to conventional therapies. Depletion of EIF4G2 also increased the prevalence of molecular markers for aggressive cell subsets, and altered their transcriptional and proteomic landscapes. Prominent among the proteins with decreased abundance were Kinesin-1 motor proteins KIF5B and KLC1, 2, 3. Multiplexed imaging of the tumors from this EC patient cohort showed a correlation between decreased protein expression of either KIF5B or KLC1, and poor survival in patients of certain grades and stages. The findings herein reveal potential novel biomarkers for Grade 2 EC with potential ramifications for patient stratification and therapeutic interventions. SignificanceDecreased EIF4G2 protein results in increased drug resistance of aggressive sub-populations of endometrial cancer cells, is associated with poor patient survival, and may serve as a novel prognosis marker for endometrial cancer.

cancer biology↗

Sedentary behavior may accelerate aging through impact on epigenome and transcriptome: lessons from muscle inactivation in Drosophila larvae

AimThe biological mechanisms linking sedentary lifestyles and metabolic derangements are incompletely understood. Our animal model mimics sedentary behavior during early life, enabling us to explore the associated chromatin epigenetic and transcriptomic landscapes. MethodsDrosophila larvae carrying a temperature-sensitive mutation in the shibire1 (shi) gene were used. shi homozygous mutant larvae undergo instant arrest of muscle contraction at a restrictive temperature (30{degrees}C), without affecting other systems. Both shi and control (y,w) larvae were held at permissive temperature (18{degrees}C), and transferred to restrictive temperature (30{degrees}C) for six hours. Larvae were then dissected, fixed, and double-labeled with antibodies specific for epigenetic marks of chromatin activation (H3K9ac) and repression (H3K27me3), and their fluorescence signal was quantified. In addition, whole genome analysis of RNA-Pol II binding to DNA in muscle-specific inactive, or control larvae was performed using muscle-specific targeted DamID (TaDa) protocol. ResultsInducing muscle inactivity in shi larvae at 300C yielded a significantly higher ratio between chromatin activation and repression, based upon H3K9ac/H3K27me3 signals (p=0.025), relative to all control groups for which this ratio was comparable (p=0.995). Furthermore, muscle inactivation led to altered Pol II binding to 121 out of 2010 genes (6%). The suppressed protein-coding genes included genes associated with longevity, DNA repair, muscle function, and ubiquitin-dependent proteostasis. In addition, a three-fold enrichment of genes coding for lncRNAs was noted in the muscle-inactive larvae. ConclusionInducing muscle inactivation exerted a multi-level impact upon chromatin, triggering an altered epigenetic balance, as well as downregulation of the transcriptional activity of genes essential for muscle function, carbohydrate metabolism, longevity and others. Extrapolating these findings to humans holds promise for establishing a molecular link between sedentary behavior and metabolic diseases.

physiology↗

PRDM16 co-operates with LHX2 to shape the human brain

PRDM16 is a dynamic transcriptional regulator of various stem cell niches, including adipocytic, hematopoietic, cardiac progenitors, and neural stem cells. PRDM16 has been suggested to contribute to 1p36 deletion syndrome, one of the most prevalent subtelomeric microdeletion syndromes. We report a patient with a de novo nonsense mutation in the PRDM16 coding sequence, accompanied by lissencephaly and microcephaly features. Human stem cells were genetically modified to mimic this mutation, generating cortical organoids that exhibited altered cell cycle dynamics. RNA sequencing of cortical organoids at day 32 unveiled changes in cell adhesion and WNT-signaling pathways. ChIP-seq of PRDM16 identified binding sites in postmortem human fetal cortex, indicating the conservation of PRDM16 binding to developmental genes in mice and humans, potentially at enhancer sites. A shared motif between PRDM16 and LHX2 was identified and further examined through comparison with LHX2 ChIP-seq data from mice. These results suggested a collaborative partnership between PRDM16 and LHX2 in regulating a common set of genes and pathways in cortical radial glia cells, possibly via their synergistic involvement in cortical development.

developmental biology↗

Metabolic rewiring of the probiotic bacterium Lacticaseibacillus rhamnosus GG contributes to cell wall remodeling and antimicrobials production

Lacticaseibacillus rhamnosus GG (LGG) is a Gram-positive beneficial bacterium that resides in the human intestinal tract and belongs to the family of lactic acid bacteria (LAB). This bacterium is a widely used probiotic and was suggested to provide numerous benefits for human health. However, as in most LAB strains, the molecular mechanisms that mediate the competitiveness of probiotics under different diets remain unknown. Fermentation is a fundamental process in LAB, allowing the oxidation of simple carbohydrates (e.g., glucose, mannose) for energy production under conditions of oxygen limitation, as in the human gut. Our results indicate that fermentation reshapes the metabolome, volatilome, and proteome architecture in LGG. Furthermore, fermentation alters cell envelope remodeling and peptidoglycan biosynthesis, which leads to altered cell wall thickness, aggregation properties, and cell wall composition. In addition, fermentable sugars induced secretion of known and novel metabolites and proteins targeting the enteric pathogens Enterococcus faecalis and Salmonella Enterica serovar Typhimurium. Overall, our results link the common metabolic regulation of cell wall remodeling, aggregation to host tissues, biofilm formation in probiotic strains, and connect the production of antimicrobial effectors with metabolome reprogramming. These findings provide novel insights into the role of nutrition in the establishment of LGG in the gastrointestinal tract.

microbiology↗

Pten regulates endocytic trafficking of cell adhesion and signaling molecules to pattern the retina

The retina is an exquisitely patterned tissue, with neuronal somata positioned at regular intervals to completely sample the visual field. Cholinergic amacrine cells are spectacular exemplars of precision, distributing in two radial layers and tangentially, forming regular mosaics. Here, we investigated how the intracellular phosphatase Pten and the cell adhesion molecule Dscam cooperate to regulate amacrine cell patterning. Using double mutants to test epistasis, we found that Pten and Dscam function in parallel pathways to regulate amacrine cell positioning. Mechanistically, Pten regulates endocytic remodeling of cell adhesion molecules (Dscam, Megf10, Fat3), which are aberrantly redistributed in Pten conditional-knock-out (cKO) amacrine cells. Furthermore, extracellular vesicles derived from multivesicular endosomes have altered proteomes in PtencKO retinas. Consequently, Wnt signaling is elevated in PtencKO retinal amacrine cells, the pharmacological disruption of which phenocopies PtencKO patterning defects. Pten thus controls endocytic trafficking of critical cell adhesion/signaling molecules to control amacrine cell spacing. HIGHLIGHTSO_LIPten and Dscam act in parallel pathways to regulate amacrine cell spacing C_LIO_LIEndocytic remodeling of cell adhesion molecules is perturbed in PtencKO retinas C_LIO_LIExtracellular vesicle content is altered in PtencKO retinas C_LIO_LIPerturbation of Wnt signaling phenocopies defects in amacrine cell positioning C_LI eTOC BLURBPatterns in nature range from stereotyped distributions of colored patches on butterfly wings to precise neuronal spacing in the nervous system. Waddington proposed that built-in constraints canalize developmental patterns. Touahri et al. identified Pten-mediated endocytic trafficking of cell adhesion/signaling molecules as a novel constraint measure controlling retinal amacrine cell patterning.

neuroscience↗

Arabidopsis thaliana induces multigenerational stress tolerance against biotic and abiotic stressors and memorization of host colonization in Bacillus subtilis

Bacillus subtilis is a beneficial bacterium that supports plant growth and protects it from bacterial, fungal, and viral infections. Here using a simplified system of B. subtilis, and Arabidopsis thaliana interactions, we found that history-dependent behavior is a potentially important manifestation of host colonization, worth classifying and quantifying. To study history-dependent adaptation to plant hosts, we develop a simple framework for measuring the physiological memory of B. subtilis following its interaction with Arabidopsis thaliana. We found that A. thaliana secretions reduce the lag time in pre-exposed bacteria compared with naive B. subtilis cells, even after their complete removal. Pre-exposed B. subtilis cells colonized plant roots more efficiently than naive bacteria, and were more resistant to biotic and abiotic stressors such as salicylic acid, and high salinity. Descendants of bacteria treated with plant secretions had an advantage in the competition against unexposed bacteria for root colonization. The effect of plant secretions was independent of their roles as nitrogen and carbon sources. Transcriptome analysis of both ancestors and descendants revealed that a specific set of plant-induced processes, among them c-di-AMP homeostasis, and the general stress response, maintain the signature of association with the plant in descendants of pre-exposed bacteria. Consistently, plant secretions compensated for the loss of c-di-AMP cyclases but required the general stress response and the master regulator Spo0A to exert their short and long-term effects. Overall, our work demonstrates that bacterial memory manifested by multigenerational reversible adaptation to plant hosts confirms an advantage to symbiotic bacteria during competition.

microbiology↗

LIS1 RNA-binding orchestrates the mechanosensitive properties of embryonic stem cells in AGO2-dependent and independent ways

Lissencephaly-1 (LIS1) is associated with neurodevelopmental diseases and is known to regulate the activity of the molecular motor cytoplasmic dynein. Here we show that LIS1 is essential for the viability of mouse embryonic stem cells (mESCs), and it regulates the physical properties of these cells. LIS1 dosage substantially affects gene expression, and we uncovered an unexpected interaction of LIS1 with RNA and RNA-binding proteins, most prominently the Argonaute complex. We demonstrate that LIS1 overexpression partially rescued the expression of extracellular matrix (ECM) and mechanosensitive genes conferring stiffness to Argonaute null mESCs. Collectively, our data transforms the current perspective on the roles of LIS1 in post- transcriptional regulation underlying development and mechanosensitive processes.

cell biology↗

Global analysis of human-to-mouse intercellular RNA transfer in cell culture

Full-length mRNAs can transfer between adjacent mammalian cells via direct cell-to-cell connections called tunneling nanotubes (TNTs). However, the extent of mRNA transfer at the transcriptome-wide level (the transferome) is unknown. Here, we analyzed whole transcriptome mRNA and lncRNA transfer between heterogeneous human-mouse cell populations in in vitro co-culture using RNA-sequencing. Our data indicate that mRNA transfer is non-selective, prevalent across the human transcriptome, and that the amount of transfer to mouse embryonic fibroblasts (MEFs) strongly correlates with the endogenous level of gene expression in donor human breast cancer cells (MCF7). These results were validated by both quantitative RT-PCR and in situ hybridization, and analysis shows that typically <1% of endogenous mRNAs and lncRNAs undergo transfer. Non-selective expression-dependent RNA transfer was further validated using synthetic RNA reporters. Notably, significant differential changes in the native MEF transcriptome were observed in response to co-culture, including the upregulation of multiple cancer and cancer-associated fibroblast-related genes and pathways. Together, these results lead us to suggest that TNT-mediated RNA transfer could be a phenomenon of physiological importance under both normal and pathogenic conditions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=183 SRC="FIGDIR/small/470233v2_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@13a7176org.highwire.dtl.DTLVardef@1ef1c75org.highwire.dtl.DTLVardef@1355eeforg.highwire.dtl.DTLVardef@ebc275_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

Non-Coding Genetic Analysis Implicates Interleukin 18 Receptor Accessory Protein 3'UTR in Amyotrophic Lateral Sclerosis

The non-coding genome is substantially larger than the protein-coding genome but is largely unexplored by genetic association studies. Here, we performed region-based burden analysis of >25,000 variants in untranslated regions of 6,139 amyotrophic lateral sclerosis (ALS) whole-genomes and 70,403 non-ALS controls. We identified Interleukin-18 Receptor Accessory Protein (IL18RAP) 3'UTR variants significantly enriched in non-ALS genomes, replicated in an independent cohort, and associated with a five-fold reduced risk of developing ALS. Variant IL18RAP 3'UTR reduces mRNA stability and the binding of RNA-binding proteins. Variant IL18RAP 3'UTR further dampens neurotoxicity of human iPSC-derived C9orf72-ALS microglia that depends on NF-{kappa}B signaling. Therefore, the variant IL18RAP 3'UTR provides survival advantage for motor neurons co-cultured with C9-ALS microglia. The study reveals direct genetic evidence and therapeutic targets for neuro-inflammation, and emphasizes the importance of non-coding genetic association studies. One Sentence SummaryNon-coding genetic variants in IL-18 receptor 3UTR decrease ALS risk by modifying IL-18-NF-{kappa}B signaling in microglia.

neuroscience↗