Intron 5 of Ars2 contains internal ribosomal entry sites that control expression of cytoplasmic ARS2 protein isoforms
| dc.contributor.author | Ngo, Quang Loc | |
| dc.contributor.supervisor | Howard, Perry L. | |
| dc.date.accessioned | 2025-01-08T21:14:05Z | |
| dc.date.available | 2025-01-08T21:14:05Z | |
| dc.date.issued | 2024 | |
| dc.degree.department | Department of Biochemistry and Microbiology | |
| dc.degree.level | Master of Science MSc | |
| dc.description.abstract | Ars2 is an essential gene in RNA metabolism that can undergo alternative splicing in which either all or a portion of its highly conserved intron 5 is retained. The retention of this intron 5, while resulting in transcripts with long 5’UTRs and uORFs that are sensitive to nonsense-mediated decay and are suboptimal to cap-dependent translation, generates cytoplasmic protein isoform of ARS2 (ARS2c) that are required for response to arsenic stress. Using a reporter plasmid that can generate circular RNAs, I demonstrated that mouse Ars2 intron 5 contains at least 3 internal ribosomal entry sites (IRESs). The presence of these IRESs within intron 5 may explain the translation of ARS2c, and its upregulation in arsenic stress, which normally result in global attenuation of cap-dependent translation. Structural prediction in combination with mutagenesis indicate that these IRESs are highly structured and form pseudoknots at their 3’ ends which are important for their activity. Additionally, my reporter system also indicated that intron 5 and its splice variants contain regulatory elements that modulate the activity of the IRESs. Taken together, my findings provide mechanistic insights into the translation controls of ARS2c. Given that ARS2c is involved in cellular stress response and is a potential cancer suppressor, this work may aid in the development of novel cancer therapeutic strategies. | |
| dc.description.embargo | 2025-12-18 | |
| dc.description.scholarlevel | Graduate | |
| dc.identifier.uri | https://hdl.handle.net/1828/20925 | |
| dc.language | English | eng |
| dc.language.iso | en | |
| dc.rights | Available to the World Wide Web | |
| dc.subject | Ars2 | |
| dc.subject | Cytoplasmic Ars2 | |
| dc.subject | Cellular stress | |
| dc.subject | Internal ribosomal entry sites | |
| dc.subject | Alternative splicing | |
| dc.subject | Retained intron | |
| dc.subject | Translation | |
| dc.subject | Cap-independent translation | |
| dc.title | Intron 5 of Ars2 contains internal ribosomal entry sites that control expression of cytoplasmic ARS2 protein isoforms | |
| dc.type | Thesis |