Identifying Differential Gene Expression Related to Spinocerebellar Ataxia Type 3 in the Brain of Model Mice to Reveal Potential Pathological Mechanisms

Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominantly inherited neurodegenerative disorder caused by aggregation of polyglutamine ataxin-3 protein in the cerebellum and brainstem. The causative mechanisms of this disease have not been clearly identified in previous research, especially molecular changes that occur in the affected regions of the brain in disease phenotypes. Different differential gene expression (DGE) events identified in the brain of SCA3 mice can provide insights into biological changes occurring through stages of disease pathogenesis. RNA sequencing (RNA-seq) data collected from the brainstem and cerebellum of SCA3 model mice and wild-type (WT) mice of different ages is studied with DGE analysis programs to determine differentially expressed genes (DEGs) at different times in the lives of disease model mice compared to WT mice. No DEG was identified in the brain of 2-month-old SCA3 model mice, and 18, 10, and 5 DEGs were identified in the brain of 4-, 12-, and 17.5-month-old SCA3 model mice, respectively. The genes are involved in various distinct biological processes, including neurotransmission, white matter maturation, cell signaling, cell metabolism, and more. Different DEGs are identified in the brain of 4-, 12-, and 17.5-month-old SCA3 model mice, causing biological changes that may lead to disease phenotypes in early, mid, and late stages of disease progression. Neuronal dysfunction is a major consequence of differential expression in 4- and 12-month-old mice while DGE has more extended effects in 17.5-month-old mice.