Project description:This study investigates the role of peroxiredoxin 2 (PRDX2) in mediating oxidative adaptations in human skeletal muscle myotubes subjected to mechanical contraction and hydrogen peroxide (H2O2) exposure. additionally, the effect of an electrical stimulation protocol was assessed pre and post PRDX2 KD along with two concentrations of H2O2.
Project description:Background: Prion diseases such as bovine spongiform encephalopathies (BSE) are transmissible neurodegenerative diseases which are presumably caused by an infectious conformational isoform of the cellular prion protein. Previous work has provided evidence that in murine prion disease the endogenous retrovirus (ERV) expression is altered in the brain. To determine if prion-induced changes in ERV expression are a general phenomenon we used a non-human primate model for prion disease. Results: Cynomolgus macaques (Macaca fasicularis) were infected intracerebrally with BSE-positive brain stem material from cattle and allowed to develop prion disease. Brain tissue from the basis pontis and vermis cerebelli of the six animals and the same regions from four healthy controls were subjected to ERV expression profiling using a retrovirus-specific microarray and quantitative real-time PCR. We could show that Class I gammaretroviruses HERV-E4-1, ERV-9, and MacERV-4 increase expression in BSE-infected macaques. In a second approach, we analysed ERV-K-(HML-2) RNA and protein expression in extracts from the same cynomolgus macaques. Here we found a significant downregulation of both, the macaque ERV-K-(HML-2) Gag protein and RNA in the frontal/parietal cortex of BSE-infected macaques. Conclusions: We provide evidence that dysregulation of ERVs in response to BSE-infection can be detected on both, the RNA and the protein level. To our knowledge, this is the first report on the differential expression of ERV-derived structural proteins in prion disorders. Our findings suggest that endogenous retroviruses may induce or exacerbate the pathological consequences of prion-associated neurodegeneration. Cynomolgus macaques (Macaca fasicularis) were infected intracerebrally with BSE-positive brain stem material from cattle and allowed to develop prion disease. Brain tissue from the basis pontis and vermis cerebelli of the six animals and the same regions from four healthy controls were subjected to ERV expression profiling using a retrovirus-specific microarray and quantitative real-time PCR. In a second approach, ERV-K-(HML-2) RNA and protein expression was analysed in extracts from the same cynomolgus macaques.
Project description:Supported by the Michael J Fox Foundation we established a biorepository of blood cells from G2019S LRRK2-PD patients recruited at the Hospital Clínic de Barcelona (Barcelona). Using this cohort, we performed a phospho-proteomic pilot study by mass spectrometry and identified a differential combination of phosphorylated proteins associated with the G2019S mutation. Here, we aim to validate and expand these findings using additional G2019S and R1441G cohorts (PMID: 35049090 By state-of-the-art DIA phospho-proteomics we aim to validate and expand our preliminary findings in additional G2019S and R1441G LRRK2 cohorts of similar design, size, and blood cell collection methods collected at additional centers in Spain (Hospital de Valdecilla in Santander, Hospital de Donostia in San Sebastian). We expect to identify differential protein phosphorylation changes in LRRK2-PD patients affected by the G2019S and R1441G mutations that could be useful as LRRK2 pharmacodynamic biomarkers. In asymptomatic LRRK2 mutation carriers, we will explore the presence of these phosphorylation changes and evaluate their applicability as early disease biomarkers.
Project description:Supported by the Michael J Fox Foundation we established a biorepository of blood cells from G2019S LRRK2-PD patients recruited at the Hospital Clínic de Barcelona (Barcelona). Using this cohort, we performed a phospho-proteomic pilot study by mass spectrometry and identified a differential combination of phosphorylated proteins associated with the G2019S mutation. Here, we aim to validate and expand these findings using additional G2019S and R1441G cohorts (PMID: 35049090 By state-of-the-art DIA phospho-proteomics we aim to validate and expand our preliminary findings in additional G2019S and R1441G LRRK2 cohorts of similar design, size, and blood cell collection methods collected at additional centers in Spain (Hospital de Valdecilla in Santander, Hospital de Donostia in San Sebastian). We expect to identify differential protein phosphorylation changes in LRRK2-PD patients affected by the G2019S and R1441G mutations that could be useful as LRRK2 pharmacodynamic biomarkers. In asymptomatic LRRK2 mutation carriers, we will explore the presence of these phosphorylation changes and evaluate their applicability as early disease biomarkers.
Project description:The experiment was designed to gain more insight into the role of DNA (de)methylation in the regulation of Arabidopsis thaliana gene transcription during a compatible interaction with the downy mildew pathogen Hyaloperonospora arabidopsidis strain WACO9 (Hpa). For this study, comparisons were made between Col-0 (wild-type), nrpe1-11 (which is affected in DNA methylation and globally hypo-methylated) and ros1-4 (impaired in DNA de-methylation and globally hyper-methylated). The latter two mutants have opposite phenotypes with respect to basal resistance and salicylic acid-dependent defence against Hpa. Samples were taken at 48 and 72 hours after spray-inoculation with either 10^5 spores ml^-1 Hyaloperonospora arabidopsidis strain WACO9 in water or water only (mock).
Project description:Beta-amino butyric acid (BABA) is an endogenous stress signalling molecule in plants. External application (e.g. by soil-drenching) of BABA induces high levels of resistance in Arabidopsis (and other plants) against the oomycete pathogen Hyaloperonospora arabidopsidis. However, high doses of BABA also trigger a metabolic stress response and stunt plant growth. Perception of BABA is mediated by the protein IBI1. The ibi1-1 mutant is deficient in BABA-induced resistance, but hypersensitive to BABA-induced stress. To identify pathways that contribute to BABA-induced resistance and stress, respectively, we compared the transcriptome of Arabidopsis wild-type and ibi1-1 mutant plants after pre-treatment with water or BABA, followed by inoculation with Hyaloperonospora arabidopsidis (or mock).
Project description:Down syndrome (DS) results from trisomy of human chromosome 21 (HSA21), and DS research has been greatly advanced by the use of mouse models. We previously generated a humanized mouse model of DS, TcMAC21, which carries the long arm of HSA21. These mice exhibit learning and memory deficits, and may reproduce neurodevelopmental alterations observed in humans with DS. Here we performed histologic studies of the TcMAC21 forebrain from embryonic to adult stages. The TcMAC21 neocortex showed reduced proliferation of neural progenitors and delayed neurogenesis. These abnormalities were associated with a smaller number of projection neurons and interneurons. Further, (phospho-)proteomic analysis of adult TcMAC21 cortex revealed alterations in the phosphorylation levels of a series of synaptic proteins. The TcMAC21 mouse model shows similar brain development abnormalities as DS, and will be a valuable mode to investigate prenatal and postnatal causes of intellectual disability in humans with DS.
Project description:Dix domain containing 1 (Dixdc1) is an important regulator of neuronal development including cortical neurogenesis, neuronal migration and synaptic connectivity, and sequence variants in the gene have been linked to autism spectrum disorders (ASD). Previous studies indicate that Dixdc1 controls neurogenesis through Wnt signaling, while its regulation of dendrite and synapse development requires Wnt and cytoskeletal signaling. However, the prediction of these signaling pathways is primarily based on the structure of Dixdc1. Given the role of Dixdc1 in neural development and brain disorders, we hypothesized that Dixdc1 may regulate additional signaling pathways in the brain. We performed proteomic analyses of Dixdc1 KO mouse cortices to reveal such alterations.
Project description:14-3-3 proteins impact protein-protein interactions (PPIs) that regulate neuronal functions. The 14-3-3θ isoform is protective in Parkinson’s disease (PD) and Dementia with Lewy Bodies (DLB) models. Human PD and DLB brains show increased 14-3-3θ phosphorylation at S232. To understand the impact of 14-3-3θ phosphorylation on brain PPIs, we performed affinity-purification mass spectrometry (AP-MS) using S232 phospho-mutant knock-in models. Proteins binding 14-3-3θ in Cre control cortical lysates were enriched in proteins involved in neuronal morphogenesis and microtubule dynamics. We found a dramatic decrease in proteins binding to 14-3-3θ in S232D mice compared to S232A mice. Axonal trafficking associated with these differentially binding proteins. Live imaging of acidic vesicles in axons revealed reduced net velocity in S232A and S232D neurons compared to Cre controls. In S232D neurons, this was due to a dramatic increase in vesicle pausing, while S232A neurons showed reduced segmental velocity, suggesting disrupted dynein motility. We conclude 14-3-3θ phosphorylation fine tunes axonal transport of acidic vesicles. Disruption of axonal transport with aberrant phosphorylation observed in PD and DLB could contribute to impaired clearance of aggregated proteins in these disorders.