Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ.
To mitigate the devastating effects of unrepaired DNA damage, prokaryotes and eukaryotes alike have an abundance of mechanisms to correct potentially genome-destabilising insults as and when they arise. DNA repair helicases play an important role in coordinating this repair. Of particular intere...
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| Format: | Thesis (University of Nottingham only) |
| Language: | English |
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2024
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| Online Access: | https://eprints.nottingham.ac.uk/77398/ |
| _version_ | 1848800992391331840 |
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| author | Betts, Hannah |
| author_facet | Betts, Hannah |
| author_sort | Betts, Hannah |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | To mitigate the devastating effects of unrepaired DNA damage, prokaryotes and eukaryotes alike have an abundance of mechanisms to correct potentially genome-destabilising insults as and when they arise. DNA repair helicases play an important role in coordinating this repair.
Of particular interest is the human DNA repair helicase HelQ – a lesser-characterized protein, whose deletion in mice manifests as an increased prevalence of ovarian tumours and infertility. HelQ is thought to stabilize stalled replication forks in a recombination-independent manner. This includes stalled forks caused both by interstrand crosslinks and R-loops – RNA:DNA hybrids which in excess contribute to genome instability. In this respect, HelQ plays an anti-cancer role for the human genome. HelQ is known to interact with Replication Protein A (RPA), a ssDNA binding protein involved in homologous recombination and other repair mechanisms, known to stimulate the helicase activity of HelQ.
To investigate the function of HelQ in the context of R- loops resolution, we present immunocytochemical data indicating a possible but unverified link between HelQ expression and nuclear R-loop levels. Therefore, we further employ dot-blot based immunoassays to examine the factors contributing to R-loop removal, and report that HelQ is strongly associated with R-loop homeostasis through an ATP dependent and RPA-stimulated R-loop clearing role.
We further present biochemical data examining the structure of the N-terminal region of HelQ (N-HelQ). We provide supporting evidence that this protein fragment exhibits considerable intrinsic disorder. Experimentation with nuclear magnetic resonance (NMR) with N-HelQ and RPA suggest that N-HelQ is responsible for the HelQ:RPA interaction. |
| first_indexed | 2025-11-14T21:00:22Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-77398 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T21:00:22Z |
| publishDate | 2024 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-773982024-07-24T04:41:01Z https://eprints.nottingham.ac.uk/77398/ Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. Betts, Hannah To mitigate the devastating effects of unrepaired DNA damage, prokaryotes and eukaryotes alike have an abundance of mechanisms to correct potentially genome-destabilising insults as and when they arise. DNA repair helicases play an important role in coordinating this repair. Of particular interest is the human DNA repair helicase HelQ – a lesser-characterized protein, whose deletion in mice manifests as an increased prevalence of ovarian tumours and infertility. HelQ is thought to stabilize stalled replication forks in a recombination-independent manner. This includes stalled forks caused both by interstrand crosslinks and R-loops – RNA:DNA hybrids which in excess contribute to genome instability. In this respect, HelQ plays an anti-cancer role for the human genome. HelQ is known to interact with Replication Protein A (RPA), a ssDNA binding protein involved in homologous recombination and other repair mechanisms, known to stimulate the helicase activity of HelQ. To investigate the function of HelQ in the context of R- loops resolution, we present immunocytochemical data indicating a possible but unverified link between HelQ expression and nuclear R-loop levels. Therefore, we further employ dot-blot based immunoassays to examine the factors contributing to R-loop removal, and report that HelQ is strongly associated with R-loop homeostasis through an ATP dependent and RPA-stimulated R-loop clearing role. We further present biochemical data examining the structure of the N-terminal region of HelQ (N-HelQ). We provide supporting evidence that this protein fragment exhibits considerable intrinsic disorder. Experimentation with nuclear magnetic resonance (NMR) with N-HelQ and RPA suggest that N-HelQ is responsible for the HelQ:RPA interaction. 2024-07-24 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en cc_by https://eprints.nottingham.ac.uk/77398/1/H%20Betts%20Thesis%20PhD%20-%2014242934%20-%20Corrections%20Document%20Completed.pdf Betts, Hannah (2024) Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. PhD thesis, University of Nottingham. DNA helicases HelQ |
| spellingShingle | DNA helicases HelQ Betts, Hannah Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title | Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title_full | Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title_fullStr | Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title_full_unstemmed | Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title_short | Mechanisms of Replication Protein A-dependent R-loop resolution by the human DNA repair helicase, HelQ. |
| title_sort | mechanisms of replication protein a-dependent r-loop resolution by the human dna repair helicase, helq. |
| topic | DNA helicases HelQ |
| url | https://eprints.nottingham.ac.uk/77398/ |