Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.554661
Title: Involvement of human DNA polymerase kappa in nucleotide excision repair
Author: Cloney, Ross
Awarding Body: University of Sussex
Current Institution: University of Sussex
Date of Award: 2011
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
Nucleotide excision repair is one of the major repair pathways responsible for identifying and removing lesions in the DNA double helix. In higher eukaryotes, nucleotide excision repair is a coordinated response of over 30 proteins recruited in an ordered procession with distinct roles in the recognition, removal and repair of said lesions. A key step in the completion of the repair process is the resynthesis of the excised strand using the undamaged partner as a template. DNA polymerase kappa (polκ), a member of the Y-family, has been shown to have a role in nucleotide excision repair distinct from its traditional role in translesion synthesis. Cell lines lacking polκ showed clear defects in nucleotide excision repair and increased ultraviolet light sensitivity. Building on this established work, conserved residues were identified in the C-terminus of human polκ and mutated to alanines. Under transient expression, mutations in the ubiquitin binding domains severely impaired the recruitment to sites of damage. Cell lines defective in polκ that stably expressed these mutant polymerases showed sensitivity to ultraviolet radiation following exposure; intriguingly, this defect seems confined to the global genomic repair pathway as no substantial defect in transcription-coupled repair was observed. Following on from these observations, immunoprecipitation of the polymerase and partner proteins was investigated in an attempt to identify interactions disrupted by the mutations to the ubiquitin binding domains. These experiments indicated impairment in binding to ubiquitinated PCNA in the mutants. In further work, the recruitment of wild-type human polκ was shown to be independent of the 3' incision by the nuclease XPG during the repair process, consistent with a recently proposed model for NER.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.554661  DOI: Not available
Keywords: QD0415 Biochemistry ; QH0426 Genetics
Share: