Investigating the role of serine-ADP-ribosylation in human cells
<p>ADP-ribosylation (ADPr) is a widespread post-translational modification that controls many cellular processes, in particular DNA repair. Poly(ADP-ribose) polymerase 1 (PARP1) is the main ADPr enzyme that performs about 85-90% of DNA damage-induced ADPr. In response to DNA damage, PARP1 rapi...
| المؤلف الرئيسي: | |
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| مؤلفون آخرون: | |
| التنسيق: | أطروحة |
| اللغة: | English |
| منشور في: |
2022
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| _version_ | 1826316402359795712 |
|---|---|
| author | Prokhorova, E |
| author2 | Ahel, I |
| author_facet | Ahel, I Prokhorova, E |
| author_sort | Prokhorova, E |
| collection | OXFORD |
| description | <p>ADP-ribosylation (ADPr) is a widespread post-translational modification that controls many cellular processes, in particular DNA repair. Poly(ADP-ribose) polymerase 1 (PARP1) is the main ADPr enzyme that performs about 85-90% of DNA damage-induced ADPr. In response to DNA damage, PARP1 rapidly binds to DNA ends at the sites of DNA damage and modifies itself, histones and other proteins, thus promoting and regulating DNA repair. However, despite the critical role of PARP1 in DNA repair, for over 50 years the amino acid specificity of PARP1 remained controversial. Recently, our group and others discovered that PARP1 in complex with HPF1 predominantly performs ADPr at serine residues, both in response to exogenous DNA damage and under physiological conditions, and ARH3 is the hydrolase responsible for its timely reversal.</p>
<p>Here, we assessed the abundance of serine-ADPr in human cells, and performed the validation of several serine-ADPr substrates, including histones. Our results established serine as the primary site of ADPr in DNA damage signalling and described serine-ADPr as an additional component of histone code.</p>
<p>Then, we investigated the relationship between the levels of physiological serine-ADPr and cell sensitivity to PARP inhibitors, which are currently approved or in clinical trials against various types of cancer. We demonstrated that serine-ADPr, in particular on PARP1 serines 499, 507 and 519, counteracts PARP inhibitor-induced DNA damage and cell death, contributing to PARP inhibitor resistance.</p>
<p>Furthermore, we discovered a synthetic lethal interaction between ARH3 and the main poly-ADPr hydrolase PARG. We showed that simultaneous suppression of the two hydrolases results in excessive accumulation of poly-ADPr on serine residues, which disrupts histone modification and transcription states, and eventually leads to PARP-dependent cell death.</p>
<p>Overall, our findings provide novel insights into the role of serine-ADPr in human cells and highlight serine-ADPr regulators HPF1 and ARH3 as novel biomarkers for cancer cell sensitivity to PARP and PARG inhibitors. Fundamentally, our results allow us to suggest the existence of minimum and maximum thresholds for serine-ADPr, crossing of which would be detrimental to cellular homeostasis.</p> |
| first_indexed | 2024-03-07T07:33:09Z |
| format | Thesis |
| id | oxford-uuid:3e0187b6-23c8-4e47-bc38-b62df91f6ea3 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-12-09T03:44:30Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | oxford-uuid:3e0187b6-23c8-4e47-bc38-b62df91f6ea32024-12-07T15:58:54ZInvestigating the role of serine-ADP-ribosylation in human cellsThesishttp://purl.org/coar/resource_type/c_db06uuid:3e0187b6-23c8-4e47-bc38-b62df91f6ea3EnglishHyrax Deposit2022Prokhorova, EAhel, I<p>ADP-ribosylation (ADPr) is a widespread post-translational modification that controls many cellular processes, in particular DNA repair. Poly(ADP-ribose) polymerase 1 (PARP1) is the main ADPr enzyme that performs about 85-90% of DNA damage-induced ADPr. In response to DNA damage, PARP1 rapidly binds to DNA ends at the sites of DNA damage and modifies itself, histones and other proteins, thus promoting and regulating DNA repair. However, despite the critical role of PARP1 in DNA repair, for over 50 years the amino acid specificity of PARP1 remained controversial. Recently, our group and others discovered that PARP1 in complex with HPF1 predominantly performs ADPr at serine residues, both in response to exogenous DNA damage and under physiological conditions, and ARH3 is the hydrolase responsible for its timely reversal.</p> <p>Here, we assessed the abundance of serine-ADPr in human cells, and performed the validation of several serine-ADPr substrates, including histones. Our results established serine as the primary site of ADPr in DNA damage signalling and described serine-ADPr as an additional component of histone code.</p> <p>Then, we investigated the relationship between the levels of physiological serine-ADPr and cell sensitivity to PARP inhibitors, which are currently approved or in clinical trials against various types of cancer. We demonstrated that serine-ADPr, in particular on PARP1 serines 499, 507 and 519, counteracts PARP inhibitor-induced DNA damage and cell death, contributing to PARP inhibitor resistance.</p> <p>Furthermore, we discovered a synthetic lethal interaction between ARH3 and the main poly-ADPr hydrolase PARG. We showed that simultaneous suppression of the two hydrolases results in excessive accumulation of poly-ADPr on serine residues, which disrupts histone modification and transcription states, and eventually leads to PARP-dependent cell death.</p> <p>Overall, our findings provide novel insights into the role of serine-ADPr in human cells and highlight serine-ADPr regulators HPF1 and ARH3 as novel biomarkers for cancer cell sensitivity to PARP and PARG inhibitors. Fundamentally, our results allow us to suggest the existence of minimum and maximum thresholds for serine-ADPr, crossing of which would be detrimental to cellular homeostasis.</p> |
| spellingShingle | Prokhorova, E Investigating the role of serine-ADP-ribosylation in human cells |
| title | Investigating the role of serine-ADP-ribosylation in human cells |
| title_full | Investigating the role of serine-ADP-ribosylation in human cells |
| title_fullStr | Investigating the role of serine-ADP-ribosylation in human cells |
| title_full_unstemmed | Investigating the role of serine-ADP-ribosylation in human cells |
| title_short | Investigating the role of serine-ADP-ribosylation in human cells |
| title_sort | investigating the role of serine adp ribosylation in human cells |
| work_keys_str_mv | AT prokhorovae investigatingtheroleofserineadpribosylationinhumancells |