Tyrosyl DNA phosphodiesterase (TDP1) is a DNA 3'-end processing enzyme that preferentially hydrolyses the bond between the 3'-end of DNA and stalled DNA topoisomerase 1. the importance of TDP1 is highlighted by its association with the human genetic disease spinocerebellar ataxia with axonal neuropathy. TDP1 comprises of a highly conserved C-terminus phosphodiesterase domain and a less conserved N-terminus tail. the importance of the N-terminus domain was suggested by its interaction with Lig3alpha. Here we show that this interaction is promoted by serine 81 that is located within a putative S/TQ site in the N-terminus domain of TDP1. Although mutation of serine 81 to alanine had no impact on TDP1 activity in vitro and had little impact on the ability of TDP1 to mediate the rapid repair of CPT- or IR-induced DNA breaks in vivo, it led to marked reduction of protein stability. Moreover, it reduced the ability of TDP1 to promote cell survival following genotoxic stress. Together, our findings highlight a novel mechanism for regulating TDP1 function in mammalian cells that is not directly related to its enzymatic activity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.4161/cc.9.3.10598 | DOI Listing |
Bioorg Chem
December 2024
School of Pharmacy, Ningxia Medical University, Yinchuan 750004, PR China; Key Laboratory of Protection, Development and Utilization of Medicinal Resources in Liupanshan Area Ministry of Education, Ningxia Medical University, Yinchuan 750004, PR China; Collaborative Innovation Center for Ningxia Characteristic Traditional Chinese Medicine by Ningxia Hui Autonomous Region & Education Ministry of P.R. China, Ningxia Characteristic Traditional Chinese Medicine Modern Engineering and Technique Research Center, Ningxia Key Laboratory of Drug Development and Generic Drug Research, Key Laboratory of Ningxia Ethnomedicine Modernization, Ministry of Education, Yinchuan 750004, PR China. Electronic address:
Tyrosyl-DNA phosphodiesterase 1 (TDP1) is an enzyme that plays a crucial role in repairing DNA lesions caused by the entrapment of DNA topoisomerase IB (TOP1)-DNA break-associated crosslinks. TDP1 inhibitors exhibit synergistic effects with TOP1 inhibitors in cancer cells, effectively overcoming resistance to TOP1 inhibitors. Therefore, this approach presents a promising strategy for reversing tumor resistance to TOP1 inhibitors.
View Article and Find Full Text PDFCell Rep
December 2024
Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada; Biophysics Department, Faculty of Science, Cairo University, Giza 12613, Egypt. Electronic address:
Uncontrolled degradation and collapse of stalled replication forks (RFs) are primary sources of genomic instability, yet the molecular mechanisms for protecting forks from degradation/collapse remain to be fully elaborated. Here, we show that polynucleotide kinase-phosphatase (PNKP) localizes at stalled forks and protects stalled forks from excessive degradation. The loss of PNKP results in nucleolytic degradation of nascent DNA at stalled RFs.
View Article and Find Full Text PDFNucleic Acids Res
December 2024
Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, CB2 0RE, UK.
Int J Mol Sci
November 2024
Department of Medicinal Chemistry, N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, 9 Acad. Lavrentjev Ave., 630090 Novosibirsk, Russia.
Mol Biol Rep
November 2024
Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, Queen Square House, London, WC1N 3BG, UK.
Background: Spinocerebellar ataxia with axonal neuropathy type 1 (OMIM: 607250) is an extremely rare autosomal recessive disorder caused by a mutation in the tyrosyl-DNA phosphodiesterase 1 (TDP1) gene. Only a single missense variant (p.His493Arg) in this gene has been reported.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!