Expression and localization of NUB1 in Tauopathy and Alzheimer’s disease models

Alzheimer’s disease (AD) is characterized at a subcellular level by intracellular neurofibrillary tangles (NFTs), aggregates of hyperphosphorylated Tau, and by senile plaques, extracellular aggregates of amyloid beta peptides. Previous data revealed that Nedd8 ultimate buster 1 (NUB1) plays a role in reducing the aggregation and phosphorylation of Tau in an in vitro model. To clarify the role of NUB1 in AD, the spatiotemporal expression and localization of NUB1 was analyzed in T301L, a mouse model for Tauopathy characterized by NFTs, and in TASTPM mice, characterized by early development of senile plaques. The analysis revealed no change in the level of NUB1 expression in T301L mice and a significant decrease at 12 months in TASTPM mice. In brain cryosections, NUB1 expression was detected in the hippocampus and entorhinal cortex. Subcellularly, NUB1 was localized predominantly in the neuronal nuclei, but also in neuronal processes. In both mouse models at 12 months, NUB1 signal was observed to co-localize with AT8 positive cytoplasmic aggregates. Moreover in TASTPM mice, a NUB1 cytoplasmic signal was observed in non-neuronal cells. Our data confirm that NUB1 could be a therapeutic target in AD and also help to establish the appropriate window of opportunity for therapeutic intervention

Negative Regulator of Ubiquitin-Like Protein 1 modulates the autophagy-lysosomal pathway via p62 to facilitate the extracellular release of tau following proteasome impairment

Negative regulator of ubiquitin-like protein 1 (NUB1) and its longer isoform NUB1L are ubiquitin-like (UBL)/ubiquitin-associated (UBA) proteins that facilitate the targeting of proteasomal substrates, including tau, synphilin-1 and huntingtin. Previous data revealed that NUB1 also mediated a reduction in tau phosphorylation and aggregation following proteasome inhibition, suggesting a switch in NUB1 function from targeted proteasomal degradation to a role in autophagy. Here, we delineate the mechanisms of this switch and show that NUB1 interacted specifically with p62 and induced an increase in p62 levels in a manner facilitated by inhibition of the proteasome. NUB1 moreover increased autophagosomes and the recruitment of lysosomes to aggresomes following proteasome inhibition. Autophagy flux assays revealed that NUB1 affected the autophagy–lysosomal pathway primarily via the UBA domain. NUB1 localized to cytosolic inclusions with pathological forms of tau, as well as LAMP1 and p62 in the hippocampal neurons of tauopathy mice. Finally, NUB1 facilitated the extracellular release of tau following proteasome inhibition. This study thus shows that NUB1 plays a role in regulating the autophagy–lysosomal pathway when the ubiquitin proteasome system is compromised, thus contributing to the mechanisms targeting the removal of aggregation-prone proteins upon proteasomal impairment

The role of NUB1 in the clearance of tau aggregates in Alzheimer's disease

BACKGROUND: Intraneuronal aggregations of abnormal hyperphosphorylated tau are a hallmark of Alzheimer’s disease. Previous data revealed that NEDD8 ultimate buster 1 (NUB1) reduces the aggregation and phosphorylation of tau in an in vitro model. NUB1 is a ubiquitin-like (UBL)/ ubiquitin-associated (UBA) protein that targets the down regulation of ubiquitin-like modifiers (NEDD8, FAT10), and aggregation-prone proteins leading to neurodegenerative disease (synphilin-1, huntingtin). The aim of the study is to understand how NUB1 affects tau aggregation and phosphorylation. METHODS: A GFP-tau inducible neuroblastoma cell line was generated and treated with proteasome inhibitor to induce the formation of aggresomes. GFP-tau cells were transduced with NUB1 lentiviral vectors both in the absence and presence of proteasome inhibitor, followed by western blotting, filter trap assays, immunoprecipitation and immunofluorescence. RESULTS: Inhibition of the proteasome induced the formation of GFP-tau aggresomes that were positive for phospho-tau (p-tau) markers (AT8, pS396). Filter trap assays revealed that NUB1 significantly decreased the ratio of p-tau to tau in the total cellular fraction (both soluble and insoluble), as well as in only the detergent insoluble fraction, both with and without proteasome inhibition. However, the ratio of tau and p-tau in the insoluble fraction to that in the total fraction revealed that the NUB1-mediated decrease in the levels of detergent insoluble tau and p-tau exceeded that of the overall decline in total levels, suggesting NUB1 can target aggregation-prone tau and p-tau. This effect of NUB1 was more pronounced for p-tau following proteasome inhibition. Blocking the proteasome induced the upregulation of p62 and increased the ratio of LC3B-II to LC3B-I. NUB1 induced further upregulation of autophagy following proteasome inhibition as seen by an increase in the LC3B-II/LC3B-I ratio and changes in LC3B positive puncta in cells. Finally, GFP-tau aggresomes were positive for p62 and NUB1 overexpression promoted the interaction between GFP-tau and p62. CONCLUSIONS: These data suggest that NUB1 may play a role in the clearance of aggregation-prone tau and p-tau following inhibition of the proteasome via autophagy

Modelling autosomal dominant optic atrophy associated with OPA1 variants in iPSC-derived retinal ganglion cells

Autosomal dominant optic atrophy (DOA) is the most common inherited optic neuropathy, characterised by the preferential loss of retinal ganglion cells (RGCs), resulting in optic nerve degeneration and progressive bilateral central vision loss. Over 60% of genetically confirmed DOA patients carry variants in the nuclear OPA1 gene, which encodes for a ubiquitously expressed, mitochondrial GTPase protein. OPA1 has diverse functions within the mitochondrial network, facilitating inner membrane fusion and cristae modelling, regulating mitochondrial DNA maintenance and coordinating mitochondrial bioenergetics. There are currently no licensed disease-modifying therapies for DOA and the disease mechanisms driving RGC degeneration are poorly understood. Here, we describe the generation of isogenic, heterozygous OPA1 null iPSC (OPA1+/-) through CRISPR/Cas9 gene editing of a control cell line, in conjunction with the generation of DOA patient-derived iPSC carrying OPA1 variants, namely, the c.2708_2711delTTAG variant (DOA iPSC), and previously reported missense variant iPSC line (c.1334G>A, DOA+ iPSC) and CRISPR/Cas9 corrected controls. A two-dimensional (2D) differentiation protocol was used to study the effect of OPA1 variants on iPSC-RGC differentiation and mitochondrial function. OPA1+/-, DOA and DOA+ iPSC showed no differentiation deficit compared to control iPSC lines, exhibiting comparable expression of all relevant markers at each stage of differentiation. OPA1+/- and OPA1 variant iPSC-RGCs exhibited impaired mitochondrial homeostasis, with reduced bioenergetic output and compromised mitochondrial DNA maintenance. These data highlight mitochondrial deficits associated with OPA1 dysfunction in human iPSC-RGCs, and establish a platform to study disease mechanisms that contribute to RGC loss in DOA, as well as potential therapeutic interventions

Allele-specific editing ameliorates dominant retinitis pigmentosa in a transgenic mouse model

Retinitis pigmentosa (RP) is a group of progressive retinal degenerations of mostly monogenic inheritance, which cause blindness in about 1:3,500 individuals worldwide. Heterozygous variants in the rhodopsin (RHO) gene are the most common cause of autosomal dominant RP (adRP). Among these, missense variants at C-terminal proline 347, such as p.Pro347Ser, cause severe adRP recurrently in European affected individuals. Here, for the first time, we use CRISPR/Cas9 to selectively target the p.Pro347Ser variant while preserving the wild-type RHO allele in vitro and in a mouse model of adRP. Detailed in vitro, genomic, and biochemical characterization of the rhodopsin C-terminal editing demonstrates a safe downregulation of p.Pro347Ser expression leading to partial recovery of photoreceptor function in a transgenic mouse model treated with adeno-associated viral vectors. This study supports the safety and efficacy of CRISPR/Cas9-mediated allele-specific editing and paves the way for a permanent and precise correction of heterozygous variants in dominantly inherited retinal diseases

Modeling and Rescue of RP2 Retinitis Pigmentosa Using iPSC-Derived Retinal Organoids

RP2 mutations cause a severe form of X-linked retinitis pigmentosa (XLRP). The mechanism of RP2-associated retinal degeneration in humans is unclear, and animal models of RP2 XLRP do not recapitulate this severe phenotype. Here, we developed gene-edited isogenic RP2 knockout (RP2 KO) induced pluripotent stem cells (iPSCs) and RP2 patient-derived iPSC to produce 3D retinal organoids as a human retinal disease model. Strikingly, the RP2 KO and RP2 patient-derived organoids showed a peak in rod photoreceptor cell death at day 150 (D150) with subsequent thinning of the organoid outer nuclear layer (ONL) by D180 of culture. Adeno-associated virus-mediated gene augmentation with human RP2 rescued the degeneration phenotype of the RP2 KO organoids, to prevent ONL thinning and restore rhodopsin expression. Notably, these data show that 3D retinal organoids can be used to model photoreceptor degeneration and test potential therapies to prevent photoreceptor cell death

Development of the chronic obstructive pulmonary disease morning symptom diary (COPD-MSD).

BACKGROUND: The morning tends to be the most difficult time of day for many patients with chronic obstructive pulmonary disease (COPD) when symptoms can limit one's ability to perform even simple activities. Morning symptoms have been linked to higher levels of work absenteeism, thereby increasing the already substantial economic burden associated with COPD. A validated patient-reported outcome (PRO) instrument designed to capture morning symptoms will allow for a more comprehensive approach to the evaluation of treatment benefit in COPD clinical trials. METHODS: A qualitative interview study was conducted among a sample of symptomatic adults with COPD. Concept elicitation interviews (n = 35) were conducted to identify COPD morning symptoms, followed by cognitive interviews (n = 21) to ensure patient comprehension of the items, instructions and response options of the draft COPD Morning Symptom Diary (COPD-MSD). All interview transcript data were coded using ATLAS.ti software for content analysis. RESULTS: Mean age of the concept elicitation and cognitive interview sample was 65.0 years (±7.5) and 62.3 years (±8.3), respectively. The study sample represented the full range of COPD severity (Global Initiative for Chronic Lung Disease [GOLD] classifications I-IV) and included a mix of racial backgrounds, employment status and educational achievement. During the concept elicitation interviews, the three most frequently reported morning symptoms were shortness of breath (n = 35/35; 100 %), phlegm/mucus (n = 31/35; 88.6 %), and cough (n = 30/35; 85.7 %). A group of clinical and instrument development experts convened to review the concept elicitation data and develop the initial 32-item draft COPD-MSD. Cognitive interviews indicated subjects found the draft COPD-MSD to be comprehensive, clear, and easy to understand. The COPD-MSD underwent minor editorial revisions and streamlining based on cognitive interviews and input from the experts to yield the final 19-item daily diary. CONCLUSIONS: This study supports the content validity of the new COPD-MSD and positions the diary for quantitative psychometric testing

Productive integration, economic recession and employment in Europe: an assessment based on vertically integrated sectors

The Covid-19 crisis has revamped the discussion about the redefinition of GVC. This paper contributes to the debate, analysing the productive relationships between European countries in four key manufacturing activities. In particular, the paper addresses two objectives. First, it maps the degree of productive integration in Europe, focusing on the generation of employment in the production of exported intermediate inputs and final goods. Second, it provides a preliminary assessment of the potential impact on employment that the current economic crisis will have on some manufacturing activities across Europe. The analysis is realised employing the concept of vertically integrated labour (Pasinetti 1973) which allows to account for the employment directly and indirectly involved in the production of final goods. The estimations are derived from Multi-Regional Input–Output tables to map the supply chain and to differentiate between the employment involved in the production of exported intermediate inputs and final goods. The results show that most of the employment involved in the production of final output of the activities studied in the paper is linked to international trade. Although Europe shows a high degree of productive links, there are important differences in the modality of insertion in the productive structure of European countries. Moreover, the impact on the level of employment due to the current economic crisis can be significant, affecting more than 1.3 million of people in Europe. These results are relevant to policy makers, who should consider carefully the high degree of linkages of the European economies when designing industrial policies and measure of support to the economy

RUOLO DELLA METODOLOGIA GEOSTATISTICA E DELLE TECNICHE DI SIMULAZIONE NELLA VALORIZZAZIONE OTTIMALE DELLE RISERVE

Nell'articolo sono illustrati e discussi i criteri, i metodi e i risultati ottenuti per la caratterizzazione e la gestione delle riserve del giacimento utilizzando le tecniche della geostatistica mineraria nell'ambito della ottimizzazione del progetto di ristrutturazione della miniera di Funtana Raminosa e della pianificazione della produzione