Marilena Lauerer, Jennifer Faber, Nicolas Casadei, Magda M Santana, Georg Auburger, Michaela Pogoda, Jakob Admard, Lea Kaupp, Patricia Laura Kos, Mafalda Raposo, Manuela Lima, Luis Pereira de Almeida, Hector Garcia-Moreno, Paola Giunti, Jeroen de Vries, Bart P van de Warrenburg, Judith van Gaalen, Marcus Grobe-Einsler, Berkan Koyak, Kathrin Reetz, Friedrich Erdlenbruch, Heike Jacobi, Jon Infante, Holger Hengel, Ludger Schöls, Thomas Klockgether, Olaf Rieß, Jeannette Hübener-Schmid
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引用次数: 0
Abstract
Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disease whose exact disease pathogenesis is not yet fully understood. We performed a genetic in-depth analysis of ataxin-2 (ATXN2), a gene that has already been described as a modulator of neurodegenerative diseases. We focused on the influence of an intermediate CAG repeat, a 9bp duplication (9bp), and isoform expression of ATXN2 on the pathogenesis of SCA3.Clinical and genetic data from a large European SCA3 cohort (total 390 probands) were analyzed. Fragment analyses were performed to determine the cytosine-adenine-guanine (CAG) repeat length and the 9bp duplication in ATXN2. RNA sequencing was performed on blood and cerebellum to evaluate ATXN2 isoform profile. Cell culture and SCA3 mice were used to investigate the influence of intermediate ATXN2 length on ataxin-3 protein abundance, aggregation, and cell viability.SCA3 carriers with an intermediate ATXN2 repeat presented a significant increase in non-ataxic symptoms. A greater age at onset and faster disease progression were found in SCA3 carriers with a 9bp duplication. Co-expression of ATXN2 and ATXN3 in cell models revealed an influence of ATXN2 on ataxin-3 abundance and aggregation patterns. Determination of soluble ATXN2 abundance demonstrated a significant genotype-independent reduction in mouse brain. Aggregate analyses indicated that ataxin-2 is not co-localized with ataxin-3-containing aggregates.Our comprehensive genetic study confirmed ATXN2 as a modulator of SCA3 pathogenesis, including onset and presence of clinical symptoms. For the first time, the ATXN2 isoform profile was compared in blood and cerebellar tissue, revealing a unique profile depending on the genotype and tissue. Here, a significant higher expression of ATXN2 splice variant type I in blood and significantly lower expression in cerebellar tissue were found compared to ATXN2 splice variant type II. Molecular and biochemical analyses in SCA3 mice and cell culture provide further evidence on mechanistic aspects, including differences in protein abundance and co-aggregation propensity. In summary, our study provides new insights into the modulatory effects of ATXN2 on SCA3 pathogenesis.
期刊介绍:
"Acta Neuropathologica Communications (ANC)" is a peer-reviewed journal that specializes in the rapid publication of research articles focused on the mechanisms underlying neurological diseases. The journal emphasizes the use of molecular, cellular, and morphological techniques applied to experimental or human tissues to investigate the pathogenesis of neurological disorders.
ANC is committed to a fast-track publication process, aiming to publish accepted manuscripts within two months of submission. This expedited timeline is designed to ensure that the latest findings in neuroscience and pathology are disseminated quickly to the scientific community, fostering rapid advancements in the field of neurology and neuroscience. The journal's focus on cutting-edge research and its swift publication schedule make it a valuable resource for researchers, clinicians, and other professionals interested in the study and treatment of neurological conditions.