Number of the records: 1
Processing and Bypass of a Site-Specific DNA Adduct of the Cytotoxic Platinum-Acridinylthiourea Conjugate by Polymerases Involved in DNA Repair: Biochemical and Thermodynamic Aspects
- 1.
SYSNO ASEP 0554462 Document Type J - Journal Article R&D Document Type Journal Article Subsidiary J Článek ve WOS Title Processing and Bypass of a Site-Specific DNA Adduct of the Cytotoxic Platinum-Acridinylthiourea Conjugate by Polymerases Involved in DNA Repair: Biochemical and Thermodynamic Aspects Author(s) Hreusová, Monika (BFU-R)
Brabec, Viktor (BFU-R) RID, ORCID
Nováková, Olga (BFU-R) RID, ORCIDNumber of authors 3 Article number 10838 Source Title International Journal of Molecular Sciences. - : MDPI
Roč. 22, č. 19 (2021)Number of pages 18 s. Publication form Online - E Language eng - English Country CH - Switzerland Keywords intrastrand cross-link ; i klenow fragment ; translesion synthesis ; antitumor oxaliplatin ; template-primers Subject RIV CE - Biochemistry OECD category Biochemistry and molecular biology R&D Projects GA21-27514S GA ČR - Czech Science Foundation (CSF) Method of publishing Open access Institutional support BFU-R - RVO:68081707 UT WOS 000706500400001 EID SCOPUS 85116473349 DOI 10.3390/ijms221910838 Annotation DNA-dependent DNA and RNA polymerases are important modulators of biological functions such as replication, transcription, recombination, or repair. In this work performed in cell-free media, we studied the ability of selected DNA polymerases to overcome a monofunctional adduct of the cytotoxic/antitumor platinum-acridinylthiourea conjugate [PtCl(en)(L)](NO3)(2) (en = ethane-1,2-diamine, L = 1-[2-(acridin-9-ylamino)ethyl]-1,3-dimethylthiourea) (ACR) in its favored 5 degrees CG sequence. We focused on how a single site-specific ACR adduct with intercalation potency affects the processivity and fidelity of DNA-dependent DNA polymerases involved in translesion synthesis (TLS) and repair. The ability of the G(N7) hybrid ACR adduct formed in the 5 '-TCGT sequence of a 24-mer DNA template to inhibit the synthesis of a complementary DNA strand by the exonuclease-deficient Klenow fragment of DNA polymerase I (KFexo-) and human polymerases eta, kappa, and iota was supplemented by thermodynamic analysis of the polymerization process. Thermodynamic parameters of a simulated translesion synthesis across the ACR adduct were obtained by using microscale thermophoresis (MST). Our results show a strong inhibitory effect of an ACR adduct on enzymatic TLS: there was only small synthesis of a full-length product (less than 10%) except polymerase eta (similar to 20%). Polymerase eta was able to most efficiently bypass the ACR hybrid adduct. Incorporation of a correct dCMP opposite the modified G residue is preferred by all the four polymerases tested. On the other hand, the frequency of misinsertions increased. The relative efficiency of misinsertions is higher than that of matched cytidine monophosphate but still lower than for the nonmodified control duplex. Thermodynamic inspection of the simulated TLS revealed a significant stabilization of successively extended primer/template duplexes containing an ACR adduct. Moreover, no significant decrease of dissociation enthalpy change behind the position of the modification can contribute to the enzymatic TLS observed with the DNA-dependent, repair-involved polymerases. This TLS could lead to a higher tolerance of cancer cells to the ACR conjugate compared to its enhanced analog, where thiourea is replaced by an amidine group: [PtCl(en)(L)](NO3)(2) (complex AMD, en = ethane-1,2-diamine, L = N-[2-(acridin-9-ylamino)ethyl]-N-methylpropionamidine). Workplace Institute of Biophysics Contact Jana Poláková, polakova@ibp.cz, Tel.: 541 517 244 Year of Publishing 2022 Electronic address https://www.mdpi.com/1422-0067/22/19/10838
Number of the records: 1