Rotation 1: Role of DNA damage in neurodegenerative disease (ataxia telangiectasia)

BBSRC strategic theme: Understanding the rules of life

DNA damage is common to living organisms and is tackled by distinct repair mechanisms. Ataxia-telangiectasia (A-T) is a rare neurodegenerative disease associated with deficient DNA repair, manifesting progressive cerebellar neurodegeneration, telangiectasia, predisposition to cancer and immune deficiency. A-T is caused by mutations in the Ataxia-telangiectasia Mutated (ATM) gene, which encodes ATM kinase, a serine/threonine protein kinase first characterised as a critical component of the DNA damage response. Its involvement in redox homeostasis, proteostasis, nutrient management and mitochondrial health was uncovered recently. Truncating mutations in ATM result in defects in various pathways, contributing to the multisystemic nature of A-T. Persistent oxidative stress is a prominent feature of ATM deficiency and is likely to be the main contributing factor to the most devastating symptom of A-T, cerebellar ataxia. To identify therapeutic targets for rebalancing neurodegeneration in A-T patients, two whole-genome CRISPR screens have previously been conducted by the Balmus lab. Among the top enrichment hits, a transcription factor named Tfap2c was shown to rescue ATM-deficient cells under oxidative stress through its knockout. The current goal of this project is to reveal the mechanism behind this rescue, focusing on two Tfap2c isoforms and one of its interaction partners, WWOX. Complementation studies will be performed with Tfap2c and WWOX constructs with relevant mutations to reveal the significance of their interaction to the rescue process. Cell culture and molecular biology techniques including western blotting, immunofluorescence and comet assays will be used for mechanism analysis. Ultimately, it's hoped that an antisense oligonucleotide-based therapy directed at Tfap2c will be able to ameliorate neurodegenerative phenotypes of A-T patients.