Targeting Staufen 1 with antisense oligonucleotides for treating ALS and SCA2

Abstract

Staufen1 (STAU1) is a multifunctional RNA binding protein that controls mRNA degradation and subcellular localization. STAU1 interacts with the ATXN2 protein, that is polyglutamine expanded in spinocerebellar ataxia type 2 (SCA2). We previously showed that STAU1 is elevated and aggregated in cells from SCA2 patients, cells from amyotrophic lateral sclerosis (ALS) patients, and in SCA2 and ALS mouse models. We also found that reduction of STAU1 abundance in vivo by genetic interaction improved motor behavior in an SCA2 mouse model, normalized the levels of several SCA2-related proteins, and reduced aggregation of polyglutamine-expanded ATXN2. Here we developed antisense oligonucleotides (ASOs) lowering STAU1 expression toward developing a therapeutic that may be effective for treating SCA2 and ALS. We performed a screen of 118 20mer phosphorothioate 2-prime-O-methoxyethyl (MOE) ASO gapmers targeting across the STAU1 mRNA coding region for lowering STAU1 expression in HEK-293 cells. ASO hits lowering STAU1 by >45 % were rescreened in SCA2 patient fibroblasts, and 10 of these were tested for lowering STAU1 abundance in vivo in a new BAC-STAU1 mouse model. This identified efficacious ASOs targeting human STAU1 in vivo that normalized autophagy marker proteins, including ASO-45 that also targets mouse Stau1. When delivered by intracerebroventricular (ICV) injection, ASO-45 normalized autophagy markers and abnormal mRNA abundances in cerebella of ATXN2-Q127 SCA2 mice, as well as ChAT, NeuN and cleaved caspase-3 in spinal cord of Thy1-TDP-43 transgenic mice. Targeting STAU1 may be an effective strategy for treating ALS and SCA2 as well as other disorders characterized by its overabundance.

A novel naïve Bayes approach to identifying grooming behaviors in the force-plate actometric platform

“…In contrast to previous automation approaches, we used the force-plate actometer developed by Fowler and colleagues to track an rodent's center of mass and enable automated, high-throughput quantification of behavior 16 . We have previously used force plate actometery to quantify gait abnormalities in another mouse model of tic disorders 17,18 , and we have also modified force plate acometers to enable specific quantifications of gait ataxia, tremor, and other behaviors [19][20][21][22][23] . In this work, we aim to make grooming analysis higher throughput, automated, and bias-free; further, while force-plate-based metrics may not distinguish facial vs. body grooming as easily as video-based approaches, we aimed to make our procedure capable of quantifying differences in grooming behaviors based on force, which may provide mechanistic insight.…”