TDP-43 Misregulation in neurodegeneration

TDP-43 is a conserved RNA binding protein central to the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). TDP-43 normally autoregulates its expression by binding to the 3’UTR of its cognate transcript. We have linked disrupted TDP-43 autoregulation to disease, showing that disease-linked TDP-43 missense mutations disturb TDP-43 autoregulation causing a gain of function, finding that ALS patients harbour non-coding variants in the 5’ and 3’UTRs of TDP-43 that could disturb TDP-43 expression and observing that TDP-43 misregulation in mice causes selective brain atrophy reminiscent of human ALS-FTD. We will follow these leads to understand the causes and consequences of TDP-43 misregulation and elucidate therapeutic targets and biomarkers for ALS-FTD. Specifically, we will dissect the TDP-43 autoregulation protein interactome in wild-type and TDP-43 missense mutant cells by performing in-cell protein-RNA interaction studies and native mass spectrometry. To determine the significance of ALS-linked UTR variants in regulating TDP-43 expression we will perform an in-vitro CRISPR/Cas9 mutagenesis screen with parallel genomic and transcriptomic sequencing. To understand how TDP-43 misregulation causes regional and cell type-specific neurodegeneration we will use in situ sequencing of mouse brain sections to obtain transcriptomic information with single cell resolution.