Resistance to protoporphyrinogen oxidase inhibitors in giant ragweed (Ambrosia trifida).

BACKGROUND: Giant ragweed (Ambrosia trifida L.) is one of the most troublesome weed species in corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] cropping systems. Following numerous reports in 2018 of suspected herbicide resistance in several Ambrosia trifida populations from Wisconsin, our objective was to characterize the response of these accessions to acetolactate synthase (ALS), enolpyruvyl shikimate phosphate synthase (EPSPS), and protoporphyrinogen oxidase (PPO) inhibitors applied POST. RESULTS: Four accessions (AT1, AT4, AT6, and AT10) exhibited ≥ 50% plant survival after exposure to the cloransulam 3× rate. Two accessions (AT8 and AT10) and one accession (AT2) exhibited ≥ 50% plant survival after exposure to glyphosate and fomesafen 1× rates, respectively. The AT10 accession exhibited multiple resistance to cloransulam and glyphosate. The AT12 accession was 28.8-fold resistant to fomesafen and 3.7-fold resistant to lactofen. A codon change in PPX2 conferring a R98L substitution was identified as the most likely mechanism conferring PPO-inhibitor resistance. CONCLUSION: To our knowledge, this is the first confirmed case of PPO-inhibitor resistance in Ambrosia trifida globally and we identified the genetic mutation likely conferring resistance. Proactive and diversified integrated weed management strategies are of paramount importance for sustainable long-term Ambrosia trifida management. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

HDAC6 inhibition as a mechanism to prevent neurodegeneration in the mSOD1G93A mouse model of ALS.

The loss of upper and lower motor neurons, and their axons is central to the loss of motor function and death in amyotrophic lateral sclerosis (ALS). Due to the diverse range of genetic and environmental factors that contribute to the pathogenesis of ALS, there have been difficulties in developing effective therapies for ALS. One emerging dichotomy is that protection of the neuronal cell soma does not prevent axonal vulnerability and degeneration, suggesting the need for targeted therapeutics to prevent axon degeneration. Post-translational modifications of protein acetylation can alter the function, stability and half-life of individual proteins, and can be enzymatically modified by histone acetyltransferases (HATs) and histone deacetyltransferases (HDACs), which add, or remove acetyl groups, respectively. Maintenance of post-translational microtubule acetylation has been suggested as a mechanism to stabilize axons, prevent axonal loss and neurodegeneration in ALS. This study used an orally dosed potent HDAC6 inhibitor, ACY-738, prevent deacetylation and stabilize microtubules in the mSOD1G93A mouse model of ALS. Co-treatment with riluzole was performed to determine any effects or drug interactions and potentially enhance preclinical research translation. This study shows ACY-738 treatment increased acetylation of microtubules in the spinal cord of mSOD1G93A mice, reduced lower motor neuron degeneration in female mice, ameliorated reduction in peripheral nerve axon puncta size, but did not prevent overt motor function decline. The current study also shows peripheral nerve axon puncta size to be partially restored after treatment with riluzole and highlights the importance of co-treatment to measure the potential effects of therapeutics in ALS.

Exploring the Impact of Amyotrophic Lateral Sclerosis on Otolaryngological Functions.

IMPORTANCE: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive degeneration of upper and lower motor neurons at the spinal or bulbar level. OBJECTIVE: We aim to describe the most frequent otolaryngology (ORL) complaints and voice disturbances in patients with bulbar onset ALS. DESIGN: Retrospective cohort study. SETTING: Single-center study with combined ORL and ALS clinic evaluation. PARTICIPANTS: Patients with a confirmed diagnosis of ALS following an ORL visit and who underwent comprehensive voice assessments between January 2021 and January 2023. EXPOSURE: Objective voice assessments. MAIN OUTCOMES AND MEASURES: Glottal functional index (GFI), voice handicap index (VHI), reflux system index (RSI), and voice quality characteristics such as shimmer, jitter, maximum phonation time (MPT), and other essential parameters were assessed. RESULTS: One hundred and thirty-three patients (age 62.17 ± 10.79, 54.48% female) were included. Three patients were referred from the ORL department to the ALS clinic. The most frequent symptoms were; dysphagia, dysarthria, facial weakness, pseudobulbar affect, and sialorrhea. The mean of forced vital capacity was 59.85%, EAT-10 15.91 ± 11.66, RSI 25.84 ± 9.03, GFI 14.12 ± 5.58, VHI-10 42.81 ± 34.94, MPT 15.22 s ± 8.06. Many patients reported voice impairments mainly related to spastic dysarthria and the combination of lower and upper motor neuron dysarthria, hypernasality, reduced verbal expression, and articulatory accuracy. Shimmer was increased to 8.46% ± 7.20, and jitter to 2.26% ± 1.39. CONCLUSIONS AND RELEVANCE: Based on our cohort, this population with bulbar onset ALS has a higher frequency of voice disturbance characterized by hypernasality, spastic dysarthria, and reduced verbal expression. LEVEL OF EVIDENCE: Level 3.

Veterans with familial ALS and bulbar and respiratory presentations at onset had shorter survival.

OBJECTIVE: We sought to characterize the clinical prognostic factors in veterans with amyotrophic lateral sclerosis (ALS) followed in our ALS clinic. BACKGROUND: ALS is a rare, progressive neurodegenerative condition associated with decreased survival compared to that in the normal population. METHOD: The electronic medical records of 105 veterans diagnosed with ALS who are followed in our ALS clinic between 2010 and 2021 were reviewed. Approval from the institutional review board was obtained from the study protocol. Demographic and clinical variables included age at symptom onset, age at initial evaluation, survival (from symptom onset to death), gender, site of onset (appendicular, bulbar, and respiratory), initial amyotrophic lateral sclerosis functional-related score-revised (ALSFRS-R), total functional independence measure (TFIM) scores, initial forced vital capacity (FVC), and interventions (Riluzole, gastrostomy, noninvasive ventilation [NIV], and tracheostomy). Normally distributed data was expressed as mean ± standard deviation. Fischer's exact analysis of the distribution differences of categorical data. The Kaplan-Meier plot analyzed the time-to-event. RESULTS: The mean (SD) age at symptom onset was 62.0 (11.1) years, age at diagnosis was 65 (11) years, with 72% of the patients being over 60 years at diagnosis. The median survival time from symptom onset was 4.12 (3) years. Limb-onset ALS (appendicular) was the most frequent (52%) followed by bulbar-onset ALS (43%). The mean ALSFRS-R and TFIM scores were 31 (8) and 91 (25), respectively. Family history (familial), bulbar, and respiratory presentation at diagnosis were associated with shorter survival times. CONCLUSION: This study suggests that of the clinical prognostic factors veterans with familial ALS, bulbar, and respiratory onset at presentations had shorter survival. The presence of Agent Orange, PEG placement, and NIV did not affect survival.

Sigma-1 receptor recruits LC3 mRNA to ER-associated omegasomes to promote localized LC3 translation enabling functional autophagy.

Autophagosome formation initiated on the endoplasmic reticulum (ER)-associated omegasome requires LC3. Translational regulation of LC3 biosynthesis is unexplored. Here we demonstrate that LC3 mRNA is recruited to omegasomes by directly binding to the ER transmembrane Sigma-1 receptor (S1R). Cell-based and in vitro reconstitution experiments show that S1R interacts with the 3' UTR of LC3 mRNA and ribosomes to promote LC3 translation. Strikingly, the 3' UTR of LC3 is also required for LC3 protein lipidation, thereby linking the mRNA-3' UTR to LC3 function. An autophagy-defective S1R mutant responsible for amyotrophic lateral sclerosis cannot bind LC3 mRNA or induce LC3 translation. We propose a model wherein S1R de-represses LC3 mRNA via its 3' UTR at the ER, enabling LC3 biosynthesis and lipidation. Because several other LC3-related proteins use the same mechanism, our data reveal a conserved pathway for localized translation essential for autophagosome biogenesis with insights illuminating the molecular basis of a neurodegenerative disease.

TDP43 and Huntingtin Exon-1 Undergo A Conformationally Specific Interaction That Strongly Alters the Fibril Formation of Both Proteins.

Protein aggregation is a common feature of many neurodegenerative diseases. In Huntington's disease, mutant huntingtin is the primary aggregating protein, but the aggregation of other proteins, such as TDP43, is likely to further contribute to toxicity. Moreover, mutant huntingtin is also a risk factor for TDP pathology in ALS. Despite this co-pathology of huntingtin and TDP43, it remains unknown whether these amyloidogenic proteins directly interact with each other. Using a combination of biophysical methods, we show that the aggregation prone regions of both proteins, huntingtin exon-1 (Httex1) and the TDP43 low complexity domain (TDP43-LCD), interact in a conformationally specific manner. This interaction significantly slows Httex1 aggregation, while it accelerates TDP43-LCD aggregation. A key intermediate responsible for both effects is a complex formed by liquid TDP43-LCD condensates and Httex1 fibrils. This complex shields seeding competent surfaces of Httex1 fibrils from Httex1 monomers, which are excluded from the condensates. In contrast, TDP43-LCD condensates undergo an accelerated liquid-to-solid transition upon exposure to Httex1 fibrils. Cellular studies show co-aggregation of untagged Httex1 with TDP43. This interaction causes mislocalization of TDP43, which has been linked to TDP43 toxicity. The protection from Httex1 aggregation in lieu of TDP43-LCD aggregation is interesting, as it mirrors what has been found in disease models, namely that TDP43 can protect from huntingtin toxicity, while mutant huntingtin can promote TDP43 pathology. These results suggest that direct protein interaction could, at least in part, be responsible for the linked pathologies of both proteins.

Lysosomal TBK1 responds to amino acid availability to relieve Rab7-dependent mTORC1 inhibition.

Lysosomes play a pivotal role in coordinating macromolecule degradation and regulating cell growth and metabolism. Despite substantial progress in identifying lysosomal signaling proteins, understanding the pathways that synchronize lysosome functions with changing cellular demands remains incomplete. This study uncovers a role for TANK-binding kinase 1 (TBK1), well known for its role in innate immunity and organelle quality control, in modulating lysosomal responsiveness to nutrients. Specifically, we identify a pool of TBK1 that is recruited to lysosomes in response to elevated amino acid levels. This lysosomal TBK1 phosphorylates Rab7 on serine 72. This is critical for alleviating Rab7-mediated inhibition of amino acid-dependent mTORC1 activation. Furthermore, a TBK1 mutant (E696K) associated with amyotrophic lateral sclerosis and frontotemporal dementia constitutively accumulates at lysosomes, resulting in elevated Rab7 phosphorylation and increased mTORC1 activation. This data establishes the lysosome as a site of amino acid regulated TBK1 signaling that is crucial for efficient mTORC1 activation. This lysosomal pool of TBK1 has broader implications for lysosome homeostasis, and its dysregulation could contribute to the pathogenesis of ALS-FTD.

Multiple metal exposures associate with higher amyotrophic lateral sclerosis risk and mortality independent of genetic risk and correlate to self-reported exposures: a case-control study.

BACKGROUND: The pathogenesis of amyotrophic lateral sclerosis (ALS) involves both genetic and environmental factors. This study investigates associations between metal measures in plasma and urine, ALS risk and survival and exposure sources. METHODS: Participants with and without ALS from Michigan provided plasma and urine samples for metal measurement via inductively coupled plasma mass spectrometry. ORs and HRs for each metal were computed using risk and survival models. Environmental risk scores (ERS) were created to evaluate the association between exposure mixtures and ALS risk and survival and exposure source. ALS (ALS-PGS) and metal (metal-PGS) polygenic risk scores were constructed from an independent genome-wide association study and relevant literature-selected single-nucleotide polymorphisms. RESULTS: Plasma and urine samples from 454 ALS and 294 control participants were analysed. Elevated levels of individual metals, including copper, selenium and zinc, significantly associated with ALS risk and survival. ERS representing metal mixtures strongly associated with ALS risk (plasma, OR=2.95, CI=2.38-3.62, p<0.001; urine, OR=3.10, CI=2.43-3.97, p<0.001) and poorer ALS survival (plasma, HR=1.37, CI=1.20-1.58, p<0.001; urine, HR=1.44, CI=1.23-1.67, p<0.001). Addition of the ALS-PGS or metal-PGS did not alter the significance of metals with ALS risk and survival. Occupations with high potential of metal exposure associated with elevated ERS. Additionally, occupational and non-occupational metal exposures were associated with measured plasma and urine metals. CONCLUSION: Metals in plasma and urine associated with increased ALS risk and reduced survival, independent of genetic risk, and correlated with occupational and non-occupational metal exposures. These data underscore the significance of metal exposure in ALS risk and progression.

Cortical microstructural abnormalities in amyotrophic lateral sclerosis: a gray matter-based spatial statistics study.

Background: Amyotrophic lateral sclerosis (ALS)-related white-matter microstructural abnormalities have received considerable attention; however, gray-matter structural abnormalities have not been fully elucidated. This study aimed to evaluate cortical microstructural abnormalities in ALS and determine their association with disease severity. Methods: This study included 34 patients with ALS and 30 healthy controls. Diffusion-weighted data were used to estimate neurite orientation dispersion and density imaging (NODDI) parameters, including neurite density index (NDI) and orientation dispersion index (ODI). We performed gray matter-based spatial statistics (GBSS) in a voxel-wise manner to determine the cortical microstructure difference. We used the revised ALS Functional Rating Scale (ALSFRS-R) to assess disease severity and conducted a correlation analysis between NODDI parameters and ALSFRS-R. Results: In patients with ALS, the NDI reduction involved several cortical regions [primarily the precentral gyrus, postcentral gyrus, temporal cortex, prefrontal cortex, occipital cortex, and posterior parietal cortex; family-wise error (FWE)-corrected P<0.05]. ODI decreased in relatively few cortical regions (including the precentral gyrus, postcentral gyrus, prefrontal cortex, and inferior parietal lobule; FWE-corrected P<0.05). The NDI value in the left precentral and postcentral gyrus was positively correlated with the ALS disease severity (FWE-corrected P<0.05). Conclusions: The decreases in NDI and ODI involved both motor-related and extra-motor regions and indicated the presence of gray-matter microstructural impairment in ALS. NODDI parameters are potential imaging biomarkers for evaluating disease severity in vivo. Our results showed that GBSS is a feasible method for identifying abnormalities in the cortical microstructure of patients with ALS.

Circulating endocannabinoidome signatures of disease activity in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Preclinical studies of amyotrophic lateral sclerosis (ALS) have shown altered endocannabinoid (eCB) signalling that may contribute to the disease. Results from human studies are sparse and inconclusive. The aim of this study was to determine the association between serum levels of eCBs or their congeners, the so-called endocannabinoidome, and disease status and activity in ALS patients. METHODS: Serum concentrations of 2-arachidonoylglycerol and N-arachidonoylethanolamine (AEA), and AEA congeners palmitoylethanolamide (PEA), oleoylethanolamide (OEA), eicosapentaenoylethanolamide (EPEA), 2-docosahexaenoylglycerol (2-DHG) and docosahexaenoylethanolamide (DHEA) were measured in samples from 65 ALS patients, 32 healthy controls (HCs) and 16 neurological disease controls (NALS). A subset of 46 ALS patients underwent a longitudinal study. Disease activity and progression were correlated with eCB and congener levels. RESULTS: Most circulating mediators were higher in ALS than HCs (all p < 0.001), but not NALS. Across clinical stages, ALS patients showed increased levels of PEA, OEA and EPEA (all p < 0.02), which were confirmed by the longitudinal study (all p < 0.03). Serum PEA and OEA levels were independent predictors of survival and OEA levels were higher in patients complaining of appetite loss. Cluster analysis revealed two distinct profiles of circulating mediators associated with corresponding patterns of disease activity (severe vs. mild). Patients belonging to the 'severe' cluster showed significantly higher levels of OEA and PEA and lower levels of 2-DHG compared to NALS and HCs. CONCLUSION: Circulating endocannabinoidome profiles are indicative of disease activity, thus possibly paving the way to a personalized, rather than a 'one-fits-all', therapeutic approach targeting the endocannabinoidome.

An automatic measure for speech intelligibility in dysarthrias-validation across multiple languages and neurological disorders.

Introduction: Dysarthria, a motor speech disorder caused by muscle weakness or paralysis, severely impacts speech intelligibility and quality of life. The condition is prevalent in motor speech disorders such as Parkinson's disease (PD), atypical parkinsonism such as progressive supranuclear palsy (PSP), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). Improving intelligibility is not only an outcome that matters to patients but can also play a critical role as an endpoint in clinical research and drug development. This study validates a digital measure for speech intelligibility, the ki: SB-M intelligibility score, across various motor speech disorders and languages following the Digital Medicine Society (DiMe) V3 framework. Methods: The study used four datasets: healthy controls (HCs) and patients with PD, HD, PSP, and ALS from Czech, Colombian, and German populations. Participants' speech intelligibility was assessed using the ki: SB-M intelligibility score, which is derived from automatic speech recognition (ASR) systems. Verification with inter-ASR reliability and temporal consistency, analytical validation with correlations to gold standard clinical dysarthria scores in each disease, and clinical validation with group comparisons between HCs and patients were performed. Results: Verification showed good to excellent inter-rater reliability between ASR systems and fair to good consistency. Analytical validation revealed significant correlations between the SB-M intelligibility score and established clinical measures for speech impairments across all patient groups and languages. Clinical validation demonstrated significant differences in intelligibility scores between pathological groups and healthy controls, indicating the measure's discriminative capability. Discussion: The ki: SB-M intelligibility score is a reliable, valid, and clinically relevant tool for assessing speech intelligibility in motor speech disorders. It holds promise for improving clinical trials through automated, objective, and scalable assessments. Future studies should explore its utility in monitoring disease progression and therapeutic efficacy as well as add data from further dysarthrias to the validation.

Hollow tubular sea-urchin structure with high catalytic activity of NiCo2Se4@CS2 cathodes for high-performance Al/S batteries.

The shuttle effect of aluminum polysulfides (AlPSs) have been a source of concern for studying Al/S batteries. Due to the weak adsorption of CS composites, research on cathode materials for Al/S batteries has been delayed. As it is generally known that Al2S3 decomposition demands a large Gibbs free energy, this work has tried to reduce the Al2S3 decomposition potential energy. Herein, the Ni/Co bimetallic selenide reduces the energy barrier conversion and mitigates the polarization effects, while morphology control enables the storage and anchoring of S, alleviating the shuttle effect. Additionally, the intermediate products serve as single-atom catalysts, increasing the active sites, synergistically enhancing the ion diffusion kinetics. DFT calculations verify that NiCo2Se4 has a moderate Gibbs free energy change during the rate-limiting step of S reduction and the most robust adsorption energy to Al2S3. NiCo2Se4@CS2/Al has a remaining capacity of 135 mAh/g after 450 cycles (at 200 mA g-1), pioneering novel ideas for the development of Al/S batteries.

The Answer ALS return of results study: Answering the duty to disclose.

Objective: The Return of Answer ALS Results (RoAR) Study was designed to provide a mechanism for participants in Answer ALS, a large, prospectively designed natural history and biorepository study to receive select clinical genetic testing results and study participants' experience with the results disclosure. Methods: Participants consented to receive results of five ALS genes (C9orf72, SOD1, FUS, TARDP, TBK1) and/or 59 medically actionable genes as designated by the American College of Medical Genetics. Patient-reported genetic testing outcomes were measured via a post-disclosure survey. Results: Of 645 eligible Answer ALS enrollees, 143 (22%) enrolled and completed participation in RoAR. Pathogenic variants were identified in 22/143 (15.4%) participants, including 13/143 (9.0%) in ALS genes and 9/143 (6.3%) in ACMG genes. Participant-reported measures of result utility indicated the research result disclosure was as or more successful than published patient-reported outcomes of result disclosure the clinical setting. Conclusions: This study serves as a model of a "disclosure study" to share results from genomic research with participants who were not initially offered the option to receive results, and our findings can inform the design of future, large scale genomic projects to empower research participants to access their genetic information.

Taxonomic and functional changes in wheat rhizosphere microbiome caused by imidazoline-based herbicide and genetic modification.

Genetically modified (GM) crop cultivation has received a lot of attention in recent years due to the substantial public debate. Consequently, an in-depth investigation of excessively used GM herbicide-tolerant crops is a vital step for the biosafety of genetically modified plants. Several studies have been conducted to study the impact of transgenic GM crops on soil microbial composition; however, research into the effects of non-transgenic GM crops is inadequate. In the current work, high-throughput sequencing was used to evaluate the impact of the acetolactate synthase (ALS)-mutant (WK170B), its control (YN19B), and the imazamox (IM) herbicide on the wheat rhizobiome. Under normal growth conditions, our work revealed a minimal impact of ALS-mutant WK170B on the rhizosphere microbiome compared to the control YN10B, except for some cyanobacterial microorganisms that showed a significant increase in abundance. This suggests that the gene mutation could potentially have a beneficial impact on the bacterial communities present in the rhizosphere. Following IM exposure, taxonomic analysis revealed a significant reduction in the relative abundance of Ralstonia pickettii and an unidentified member of the genus Ancylothrix 8PC. Analyses of both alpha and beta diversity revealed a statistically significant increase in both microbial richness and species diversity. IM-induced relative abundance modulation was also evident through Linear discriminant analysis Effect Size (LEfSe), MetaStat, and heatmap analyses. The SIMPER analysis revealed that the microbial taxa Massilia, Limnobacter, Hydrogenophaga, Ralstonia, Nitrospira, and Ramlibacter exhibited the highest vulnerability to IM exposure. The functional attributes analysis revealed that the relative abundance of genes associated with the extracellular matrix-receptor interaction, which is responsible for structural support and stress response, increased significantly following IM exposure. Collectively, our study identifies key microbial taxa in the wheat rhizobiome that are sensitive to IM herbicides and provides a foundation for assessing the environmental risks associated with IM herbicide use.

Abnormal Splicing Events due to Loss of Nuclear Function of TDP-43: Pathophysiology and Perspectives.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are neurodegenerative diseases with a progressive and fatal course. They are often comorbid and share the same molecular spectrum. Their key pathological features are the formation of the aggregation of TDP-43, an RNA-binding protein, in the cytoplasm and its depletion from the nucleus in the central nervous system. In the nucleus, TDP-43 regulates several aspects of RNA metabolism, ranging from RNA transcription and alternative splicing to RNA transport. Suppressing the aberrant splicing events during RNA processing is one of the significant functions of TDP-43. This function is impaired when TDP-43 becomes depleted from the nucleus. Several critical cryptic splicing targets of TDP-43 have recently emerged, such as STMN2, UNC13A, and others. UNC13A is an important ALS/FTD risk gene, and the genetic variations, single nucleotide polymorphisms, cause disease via the increased susceptibility for cryptic exon inclusion under the TDP-43 dysfunction. Moreover, TDP-43 has an autoregulatory mechanism that regulates the splicing of its mRNA (TARDBP mRNA) in the healthy state. This study provides recent findings on the splicing regulatory function of TDP-43 and discusses the prospects of using these aberrant splicing events as efficient biomarkers.

Overexpression of Toxic Poly(Glycine-Alanine) Aggregates in Primary Neuronal Cultures Induces Time-Dependent Autophagic and Synaptic Alterations but Subtle Activity Impairments.

The pathogenic expansion of the intronic GGGGCC hexanucleotide located in the non-coding region of the C9orf72 gene represents the most frequent genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). This mutation leads to the accumulation of toxic RNA foci and dipeptide repeats (DPRs), as well as reduced levels of the C9orf72 protein. Thus, both gain and loss of function are coexisting pathogenic aspects linked to C9orf72-ALS/FTD. Synaptic alterations have been largely described in C9orf72 models, but it is still not clear which aspect of the pathology mostly contributes to these impairments. To address this question, we investigated the dynamic changes occurring over time at the synapse upon accumulation of poly(GA), the most abundant DPR. Overexpression of this toxic form induced a drastic loss of synaptic proteins in primary neuron cultures, anticipating autophagic defects. Surprisingly, the dramatic impairment characterizing the synaptic proteome was not fully matched by changes in network properties. In fact, high-density multi-electrode array analysis highlighted only minor reductions in the spike number and firing rate of poly(GA) neurons. Our data show that the toxic gain of function linked to C9orf72 affects the synaptic proteome but exerts only minor effects on the network activity.

Structural basis for RNA recognition by the C-terminal RRM domain of human RBM45.

RBM45 is an RNA-binding protein with roles in neural development by regulating RNA splicing. Its dysfunction and aggregation are associated with neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar dementia (FTLD). RBM45 harbors three RRM domains that potentially bind RNA. While the recognitions of RNA by its N-terminal tandem RRM domains (RRM1 and RRM2) have been well understood, the RNA-binding property of its C-terminal RRM (RRM3) remains unclear. In this work, we identified that the RRM3 of RBM45 sequence-specifically binds RNA with a GACG sequence, similar but not identical to those recognized by the RRM1 and RRM2. Further, we determined the crystal structure of RBM45RRM3 in complex with a GACG sequence-containing single-stranded DNA. Our structural results, together with the RNA-binding assays of mutants at key amino acid residues, revealed the molecular mechanism by which RBM45RRM3 recognizes an RNA sequence. Our finding on the RNA-binding property of the individual RRM module of RBM45 provides the foundation for unraveling the RNA-binding characteristics of full-length RBM45 and for understanding the biological functions of RBM45.

Evaluation of the applicability of weak shoulder and arm sparing signs in amyotrophic lateral sclerosis by multiple neurologists and neurology residents: A single-center study.

INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) exhibits selective muscle weakness. The weak shoulder and arm sparing signs, assessed by a single experienced neurologist, have been reported to be superior to previous signs in sensitivity and specificity. However, it is unknown whether the same results are observed when assessed by multiple neurologists. METHODS: Subjects were retrospectively identified from our department's inpatient database from 2014 to 2023. Medical Research Council (MRC) scores of the deltoid (Del), biceps brachii (BB), triceps brachii (TB), and first dorsal interosseous (FDI) muscles were evaluated. The weak shoulder sign was defined as positive when Del was weaker than BB and TB. The arm sparing sign was defined as positive when both Del and FDI were weaker than BB and TB. Sensitivity was analyzed in all ALS patients and in subgroups based on the region of symptom onset, presence or absence of upper motor neuron (UMN) signs, and the Japanese ALS Severity Classification. RESULTS: Seventy-one patients with ALS were identified. Eight neurologists and three neurology residents evaluated each patient's MRC scores. The weak shoulder and arm sparing signs were observed in 72% and 48% of patients, respectively, with no significant difference in sensitivity across patient subgroups. DISCUSSION: The weak shoulder and arm sparing signs showed high and moderate sensitivity, respectively, consistent with a previous report, even when evaluated by multiple examiners. This expands the clinical utility and increases the reliability of these signs, potentially contributing to accurate ALS diagnosis when combined with other clinical features and objective assessments.

AAV-NRIP gene therapy ameliorates motor neuron degeneration and muscle atrophy in ALS model mice.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is characterized by progressive motor neuron (MN) degeneration, leading to neuromuscular junction (NMJ) dismantling and severe muscle atrophy. The nuclear receptor interaction protein (NRIP) functions as a multifunctional protein. It directly interacts with calmodulin or α-actinin 2, serving as a calcium sensor for muscle contraction and maintaining sarcomere integrity. Additionally, NRIP binds with the acetylcholine receptor (AChR) for NMJ stabilization. Loss of NRIP in muscles results in progressive motor neuron degeneration with abnormal NMJ architecture, resembling ALS phenotypes. Therefore, we hypothesize that NRIP could be a therapeutic factor for ALS. METHODS: We used SOD1 G93A mice, expressing human SOD1 with the ALS-linked G93A mutation, as an ALS model. An adeno-associated virus vector encoding the human NRIP gene (AAV-NRIP) was generated and injected into the muscles of SOD1 G93A mice at 60 days of age, before disease onset. Pathological and behavioral changes were measured to evaluate the therapeutic effects of AAV-NRIP on the disease progression of SOD1 G93A mice. RESULTS: SOD1 G93A mice exhibited lower NRIP expression than wild-type mice in both the spinal cord and skeletal muscle tissues. Forced NRIP expression through AAV-NRIP intramuscular injection was observed in skeletal muscles and retrogradely transduced into the spinal cord. AAV-NRIP gene therapy enhanced movement distance and rearing frequencies in SOD1 G93A mice. Moreover, AAV-NRIP increased myofiber size and slow myosin expression, ameliorated NMJ degeneration and axon terminal denervation at NMJ, and increased the number of α-motor neurons (α-MNs) and compound muscle action potential (CMAP) in SOD1 G93A mice. CONCLUSIONS: AAV-NRIP gene therapy ameliorates muscle atrophy, motor neuron degeneration, and axon terminal denervation at NMJ, leading to increased NMJ transmission and improved motor functions in SOD1 G93A mice. Collectively, AAV-NRIP could be a potential therapeutic drug for ALS.

Is gut microbiota of patients with ALS different from that of healthy individuals?

Background/aim: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Several studies have shown that alterations of microbiota increase the risk of neurodegenerative disorders. We aimed to reveal whether there is a difference in the gut microbiota of patients with ALS. Materials and methods: The participants are divided into three groups. Group 1 comprised patients with ALS. Healthy family members living in the same house of the patients formed Group 2. Lastly, sex- and age-matched healthy people were included in Group 3. Fecal samples were collected in 15-mL falcon tubes and stored at -80 °C. Genomic DNA isolation was performed on samples. Bacterial primers selected from the 16S rRNA region for the bacterial genome and ITS1 and ITS4 (internal transcribed spacer) were used for the identification of DNA. Next generation sequence analysis (NGS) and taxonomic analyses were performed at the level of bacterial phylum, class, order, family, genus, and species. Alpha and beta diversity indexes were used. The linear discriminant analysis (LDA) effect size method (LEfSe) was applied to identify a microbial taxon specific to ALS disease. Results: The relative abundances of the Succinivibrionaceae and Lachnospiraceae families were significantly lower in patients. The dominant families among patients were Streptococcaceae and Ruminococcaceae, while the dominant families among healthy controls were Bacteroidaceae and Succinivibrionaceae. The LEfSe analysis revealed that four families (Atopobiaceae, Actinomycetaceae, Erysipelatoclostridiaceae, Peptococcacceae) differed significantly between the patients and healthy controls (LDA values> 2.5, p < 0.05). Conclusion: Comparison with family members living in the same house is the strength of this study. We found that there were changes in the microbiota of the patients, consistent with the literature. Studies that analyze the composition of the gut microbiota in the predisease period may be needed to understand whether dysbiosis is caused by the mechanisms inherent in the disease or whether it is dysbiosis that initiates the disease.