Molecular mechanisms of ARF regulation in response to DNA damage

<p>DNA is a highly unstable molecule. Endogenous souces of DNA damage, such as reactive oxygen species (ROS), can cause DNA damage and it has been estimated that 20000 lesions occur in a cell per day. BER is the major pathway for the repair of these lesions and therefore maintains genome stabi...

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Main Author: Orlando, G
Other Authors: Dianov, G
Format: Thesis
Language:English
Published: 2014
Subjects:
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author Orlando, G
author2 Dianov, G
author_facet Dianov, G
Orlando, G
author_sort Orlando, G
collection OXFORD
description <p>DNA is a highly unstable molecule. Endogenous souces of DNA damage, such as reactive oxygen species (ROS), can cause DNA damage and it has been estimated that 20000 lesions occur in a cell per day. BER is the major pathway for the repair of these lesions and therefore maintains genome stability, thus preventing the development of human diseases such as neurodegenerative diseases and cancer. Therefore, if BER cannot accomplish the repair, accumulation of DNA damage occurs, triggering different cellular responses, such as cell cycle delay and senescence.</p> <p>The ARF tumour suppressor protein, the gene of which is frequently mutated in many human cancers, plays an important role in the cellular stress response by orchestrating upregulation of p53 protein. Moreover, ARF expression is upregulated in senescent cells, suggesting that ARF induction might be triggerred in response to persistent DNA damage. Although ARF has been reported to be important in the regulation of proteins involved in the DNA damage response, its role is still controversial.</p> <p>Here, it has been shown that <em>ARF</em> gene transcription is induced by DNA strand breaks (SBs) and that ARF protein accumulates in response to persistent DNA damage generated by disabling BER. These data suggest that PARP1-dependent poly(ADP-ribose) synthesis at the sites of SBs initiates DNA damage signal transduction by reducing the cellular concentration of NAD<sup>+</sup>, thus inhibiting SIRT1 activity and consequently activating E2F1-dependent <em>ARF</em> transcription. These findings suggest a vital role for ARF in DNA damage signalling, and furthermore explain the critical requirement for ARF inactivation in cancer cells, which are frequently deficient in DNA repair and accumulate DNA damage.</p>
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spelling oxford-uuid:fde8ab19-bc7f-4ad8-8396-6c5f5f385d342022-03-27T13:32:14ZMolecular mechanisms of ARF regulation in response to DNA damageThesishttp://purl.org/coar/resource_type/c_db06uuid:fde8ab19-bc7f-4ad8-8396-6c5f5f385d34DNA damage signallingEnglishOxford University Research Archive - Valet2014Orlando, GDianov, G<p>DNA is a highly unstable molecule. Endogenous souces of DNA damage, such as reactive oxygen species (ROS), can cause DNA damage and it has been estimated that 20000 lesions occur in a cell per day. BER is the major pathway for the repair of these lesions and therefore maintains genome stability, thus preventing the development of human diseases such as neurodegenerative diseases and cancer. Therefore, if BER cannot accomplish the repair, accumulation of DNA damage occurs, triggering different cellular responses, such as cell cycle delay and senescence.</p> <p>The ARF tumour suppressor protein, the gene of which is frequently mutated in many human cancers, plays an important role in the cellular stress response by orchestrating upregulation of p53 protein. Moreover, ARF expression is upregulated in senescent cells, suggesting that ARF induction might be triggerred in response to persistent DNA damage. Although ARF has been reported to be important in the regulation of proteins involved in the DNA damage response, its role is still controversial.</p> <p>Here, it has been shown that <em>ARF</em> gene transcription is induced by DNA strand breaks (SBs) and that ARF protein accumulates in response to persistent DNA damage generated by disabling BER. These data suggest that PARP1-dependent poly(ADP-ribose) synthesis at the sites of SBs initiates DNA damage signal transduction by reducing the cellular concentration of NAD<sup>+</sup>, thus inhibiting SIRT1 activity and consequently activating E2F1-dependent <em>ARF</em> transcription. These findings suggest a vital role for ARF in DNA damage signalling, and furthermore explain the critical requirement for ARF inactivation in cancer cells, which are frequently deficient in DNA repair and accumulate DNA damage.</p>
spellingShingle DNA damage signalling
Orlando, G
Molecular mechanisms of ARF regulation in response to DNA damage
title Molecular mechanisms of ARF regulation in response to DNA damage
title_full Molecular mechanisms of ARF regulation in response to DNA damage
title_fullStr Molecular mechanisms of ARF regulation in response to DNA damage
title_full_unstemmed Molecular mechanisms of ARF regulation in response to DNA damage
title_short Molecular mechanisms of ARF regulation in response to DNA damage
title_sort molecular mechanisms of arf regulation in response to dna damage
topic DNA damage signalling
work_keys_str_mv AT orlandog molecularmechanismsofarfregulationinresponsetodnadamage