The Ewing sarcoma protein regulates DNA damage-induced alternative splicing

Area of Science:

• Molecular Biology
• Cancer Research
• Genetics

Background:

• The Ewing sarcoma (EWS) protein, part of the TET family, binds RNA and DNA and is implicated in cancer.
• EWS protein expression is altered in various cancers, suggesting its role in disease pathogenesis.

Purpose of the Study:

• To investigate the role of EWS protein in DNA damage response and alternative splicing.
• To elucidate the cotranscriptional binding of EWS to target RNAs and its regulation by UV irradiation.

Main Methods:

• EWS depletion using molecular techniques.
• Analysis of alternative splicing changes in DNA repair and stress signaling genes (e.g., ABL1, CHEK2, MAP4K2).
• Chromatin and RNA crosslinking immunoprecipitation (CLIP) to study EWS-RNA interactions.
• Cell viability and proliferation assays post-UV irradiation.

Main Results:

• EWS depletion caused significant alternative splicing changes in DNA repair and genotoxic stress signaling genes.
• EWS cotranscriptionally binds to target RNAs, with reduced association observed after UV irradiation.
• UV irradiation led to EWS enrichment in nucleoli and alternative splicing alterations, reducing c-ABL protein expression.
• EWS depletion impaired cell viability and proliferation following UV exposure, an effect mitigated by restoring c-ABL expression.

Conclusions:

• EWS protein plays a critical role in the posttranscriptional regulation of DNA damage response through alternative splicing.
• EWS-mediated alternative splicing of genes like ABL1 is crucial for cellular survival and proliferation under genotoxic stress.
• These findings offer insights into the mechanisms by which TET proteins contribute to DNA damage response pathways.