Investigating TDP-43 related splicing changes and therapeutics in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive paralysing illness resulting from the degeneration of upper and lower motor neurons.

The pathological hallmark, present in 97% of patients, is the mislocalisation of TDP-43, an RNA-binding protein, from the nucleus to the cytoplasm.

Nuclear loss of TDP-43 results in aberrant splicing and the formation of cryptic exons (CEs; appearance of an exon in a normally intronic region), found in TDP-43 knockdown of human induced pluripotent stem cell (hiPSC)-derived cortical neurons and ALS post-mortem tissue.

These TDP-43-depletion related CEs may be important effectors in ALS pathophysiology through reduced expression of critical proteins and/or formation of novel potentially toxic proteins.

Using three complementary human disease models –SH-SY5Y neuronal cells, hiPSC-derived cortical neurons, and post-mortem tissue– I will investigate the molecular impact of a selection of these at the RNA and protein level, in vitro and in vivo.

In particular, I will focus on elucidating the functional impact of a CE in the insulin receptor on neuronal phenotypes and survival. By manipulating molecular pathways, I hope to identify novel ALS therapeutic targets, providing translational benefit. I also aim to rescue splicing in INSR and UNC13A, using antisense oligonucleotide and U7 small nuclear RNA therapies.