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O. I. Lavrik - One of the best experts on this subject based on the ideXlab platform.
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The contribution of PARP1, PARP2 and poly(ADP-ribosyl)ation to base excision repair in the nucleosomal context
Scientific reports, 2021Co-Authors: M. M. Kutuzov, S. N. Khodyreva, I. A. Vasil’eva, E. A. Belousova, T. A. Kurgina, A.a. Ukraintsev, O. I. LavrikAbstract:The regulation of repair processes including base excision repair (BER) in the presence of DNA damage is implemented by a cellular signal: poly(ADP-ribosyl)ation (PARylation), which is catalysed by PARP1 and PARP2. Despite ample studies, it is far from clear how BER is regulated by PARPs and how the roles are distributed between the PARPs. Here, we investigated the effects of PARP1, PARP2 and PARylation on activities of the main BER enzymes (APE1, DNA polymerase β [Polβ] and DNA ligase IIIα [LigIIIα]) in combination with BER scaffold protein XRCC1 in the nucleosomal context. We constructed nucleosome core particles with midward- or outward-oriented damage. It was concluded that in most cases, the presence of PARP1 leads to the suppression of the activities of APE1, Polβ and to a lesser extent LigIIIα. PARylation by PARP1 attenuated this effect to various degrees depending on the enzyme. PARP2 had an influence predominantly on the last stage of BER: DNA sealing. Nonetheless, PARylation by PARP2 led to Polβ inhibition and to significant stimulation of LigIIIα activities in a NAD+-dependent manner. On the basis of the obtained and literature data, we suggest a hypothetical model of the contribution of PARP1 and PARP2 to BER.
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Apurinic/Apyrimidinic Endonuclease 1 and Tyrosyl-DNA Phosphodiesterase 1 Prevent Suicidal Covalent DNA-Protein Crosslink at Apurinic/Apyrimidinic Site.
Frontiers in cell and developmental biology, 2021Co-Authors: N. A. Lebedeva, Nadejda I. Rechkunova, Anton V. Endutkin, O. I. LavrikAbstract:Bifunctional 8-oxoguanine-DNA glycosylase (OGG1), a crucial DNA-repair enzyme, removes from DNA 8-oxo-7,8-dihydroguanine (8-oxoG) with following cleavage of the arising apurinic/apyrimidinic (AP) site. The major enzyme in eukaryotic cells that catalyzes the cleavage of AP sites is AP endonuclease 1 (APE1). Alternatively, AP sites can be cleaved by tyrosyl-DNA phosphodiesterase 1 (TDP1) to initiate APE1-independent repair, thus expanding the ability of the base excision repair (BER) process. Poly(ADP-ribose) polymerase 1 (PARP1) is a regulatory protein of DNA repair. PARP2 is also activated in response to DNA damage and can be regarded as the BER participant. Here we analyze PARP1 and PARP2 interactions with DNA intermediates of the initial stages of the BER process (8-oxoG and AP-site containing DNA) and their interplay with the proteins recognizing and processing these DNA structures focusing on OGG1. OGG1 as well as PARP1 and PARP2 form covalent complex with AP site-containing DNA without borohydride reduction. AP site incision by APE1 or TDP1 removal of protein adducts but not proteins' PARylation prevent DNA-protein crosslinks.
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The contribution of PARP1, PARP2 and poly(ADP-ribosyl)ation to base excision repair in the nucleosomal context
2020Co-Authors: M. M. Kutuzov, S. N. Khodyreva, I. A. Vasil’eva, E. A. Belousova, T. A. Kurgina, A.a. Ukraintsev, O. I. LavrikAbstract:The repair processes regulation including base excision repair (BER) is implemented by a cellular signal PARylation catalysed by PARP1 and PARP2. Despite intensive studies, it is far from clear how BER is regulated by PARPs and how the roles are distributed between the PARPs. Here, we investigated the effects of PARP1, PARP2 and PARylation on activities of the main BER enzymes (APE1, Polbeta and LigIIIalfa) in combination with XRCC1 in the nucleosomal context. We constructed nucleosomes with midward- or outward-oriented damage. It was concluded that in most cases, the presence of PARP1 leads to the suppression of the activities of APE1, Polbeta, and to a lesser extent LigIIIalfa. PARylation by PARP1 attenuated this effect to various degrees. PARP2 had an influence predominantly on the last stage of BER: DNA sealing. Nonetheless, PARylation by PARP2 led to Polbeta inhibition and to significant stimulation of LigIIIalfa activities in a NAD+-dependent manner.
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Impact of PARP1, PARP2 & PARP3 on the Base Excision Repair of Nucleosomal DNA.
Advances in experimental medicine and biology, 2020Co-Authors: M. M. Kutuzov, Ekaterina A Belousova, Ekaterina S Ilina, O. I. LavrikAbstract:DNA is constantly attacked by different damaging agents; therefore, it requires frequent repair. On the one hand, the base excision repair (BER) system is responsible for the repair of the most frequent DNA lesions. On the other hand, the formation of poly(ADP-ribose) is one of the main DNA damage response reactions that is catalysed by members of the PARP family. PARP1, which belongs to the PARP family and performs approximately 90% of PAR synthesis in cells, could be considered a main regulator of the BER process. Most of the experimental data concerning BER investigation have been obtained using naked DNA. However, in the context of the eukaryotic cell, DNA is compacted in the nucleus, and the lowest compaction level is represented by the nucleosome. Thus, the organization of DNA into the nucleosome impacts the DNA-protein interactions that are involved in BER processes. Poly(ADP-ribosyl)ation (PARylation) is thought to regulate the initiation of the BER process at the chromatin level. In this review, we focus on the mechanisms involved in BER in the nucleosomal context and the potential effect of PARylation, which is catalysed by DNA-dependent PARP1, PARP2 and PARP3 proteins, on this process.
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PARPs' impact on base excision DNA repair.
DNA repair, 2020Co-Authors: O. I. LavrikAbstract:Poly(ADP-ribosyl)ation is one of immediate cellular responses to DNA damage and is catalyzed by poly(ADP-ribose) polymerases (PARPs). PARP1 is a well-known regulator of DNA repair. Another member of this family, PARP2, was discovered later. The study of PARP1 and PARP2 functions started a long time ago, and special attention has been given to the role of these enzymes in base excision repair. This review summarizes my lab's data on the functions of PARP1 and PARP2 in base excision repair as well as the results obtained in the course of our collaboration with Dr. Samuel H. Wilson.
Françoise Dantzer - One of the best experts on this subject based on the ideXlab platform.
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PARP2 mediates branched poly ADP-ribosylation in response to DNA damage.
Nature communications, 2018Co-Authors: Qian Chen, Muzaffer Ahmad Kassab, Françoise DantzerAbstract:Poly(ADP-ribosyl)ation (PARylation) is a posttranslational modification involved in multiple biological processes, including DNA damage repair. This modification is catalyzed by poly(ADP-ribose) polymerase (PARP) family of enzymes. PARylation is composed of both linear and branched polymers of poly(ADP-ribose) (PAR). However, the biochemical mechanism of polymerization and biological functions of branched PAR chains are elusive. Here we show that PARP2 is preferentially activated by PAR and subsequently catalyzes branched PAR chain synthesis. Notably, the direct binding to PAR by the N-terminus of PARP2 promotes the enzymatic activity of PARP2 toward the branched PAR chain synthesis. Moreover, the PBZ domain of APLF recognizes the branched PAR chain and regulates chromatin remodeling to DNA damage response. This unique feature of PAR-dependent PARP2 activation and subsequent PARylation mediates the participation of PARP2 in DNA damage repair. Thus, our results reveal an important molecular mechanism of branched PAR synthesis and a key biological function of branched PARylation. PARP1 and PARP2 of the PARP family enzymes are involved in DNA damage response. Here the authors report PARP2 activation mechanisms and its role in the formation of branched poly(ADP-ribose) chains in response to DNA damage.
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PARP2 deficiency affects invariant-NKT,-cell maturation and protects mice from ,Concanavalin A-induced liver injury.
American journal of physiology. Gastrointestinal and liver physiology, 2017Co-Authors: Aveline Filliol, Françoise Dantzer, Claire Piquet-pellorce, Sarah Dion, Valentine Genet, Catherine Lucas-clerc, Michel SamsonAbstract:The genetic inactivation of PARP2, but not Parp1, protects mice from concanavalin A hepatitis. Immune cell populations are lower in the thymus, but not in the spleen, liver, or bone marrow of PARP2...
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PARP2 deficiency affects invariant-NKT,-cell maturation and protects mice from ,Concanavalin A-induced liver injury.
AJP - Gastrointestinal and Liver Physiology, 2017Co-Authors: Aveline Filliol, Françoise Dantzer, Claire Piquet-pellorce, Sarah Dion, Valentine Genet, Catherine Lucas-clerc, Michel SamsonAbstract:Excessive or persistent inflammation and hepatocyte death are the key triggers of liver diseases. The poly(ADP-ribose) polymerase (PARP) proteins induce cell death and inflammation. Chemical inhibition of PARP activity protects against liver injury during concanavalin A (ConA)-induced hepatitis. In this mice model, ConA activates immune cells, which promote inflammation and induce hepatocyte death, mediated by the activated invariant natural killer T (iNKT) lymphocyte population. We analyzed immune cell populations in the liver and several lymphoid organs, such as the spleen, thymus, and bone marrow in PARP2-deficient mice to better define the role of PARP proteins in liver immunity and inflammation at steady state and during ConA-induced hepatitis. We show that 1) the genetic inactivation of PARP2, but not Parp1, protected mice from ConA hepatitis without deregulating cytokine expression and leucocyte recruitment; 2) cellularity was lower in the thymus, but not in spleen, liver, or bone marrow of PARP2-/- mice; 3) spleen and liver iNKT lymphocytes, as well as thymic T and NKT lymphocytes were reduced in PARP2 knockout mice. In conclusion, our results suggest that the defect of T-lymphocyte maturation in PARP2 knockout mice leads to a systemic reduction of iNKT cells, reducing hepatocyte death during ConA-mediated liver damage, thus protecting the mice from hepatitis.NEW & NOTEWORTHY The genetic inactivation of PARP2, but not Parp1, protects mice from concanavalin A hepatitis. Immune cell populations are lower in the thymus, but not in the spleen, liver, or bone marrow of PARP2-deficient mice compared with wild-type mice. Spleen and liver invariant natural killer T (NKT) lymphocytes, as well as thymic T and NKT lymphocytes, are reduced in PARP2-deficient mice
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Robust immunoglobulin class switch recombination and end joining in Parp9-deficient mice
Eur J Immunol, 2017Co-Authors: Isabelle Robert, Léa Gaudot, José Yélamos, Aurélia Noll, Heng-kuan Wong, Françoise Dantzer, Valérie Schreiber, Bernardo Reina-san-martinAbstract:To mount highly specific and adapted immune responses, B lymphocytes assemble and diversify their antibody repertoire through mechanisms involving the formation of programmed DNA damage. Immunoglobulin class switch recombination (CSR) is triggered by DNA lesions induced by activation-induced cytidine deaminase, which are processed to double-stranded DNA break (DSB) intermediates. These DSBs activate the cellular DNA damage response and enroll numerous DNA repair factors, involving poly(ADP-ribose) polymerases Parp1, PARP2, and Parp3 to promote appropriate DNA repair and efficient long-range recombination. The macroParp Parp9, which is overexpressed in certain lymphomas, has been recently implicated in DSB repair, acting together with Parp1. Here, we examine the contribution of Parp9 to the resolution of physiological DSBs incurred during V(D)J recombination and CSR by generating Parp9-/- mice. We find that Parp9-deficient mice are viable, fertile, and do not show any overt phenotype. Moreover, we find that Parp9 is dispensable for B-cell development. Finally, we show that CSR and DNA end-joining are robust in the absence of Parp9, indicating that Parp9 is not essential in vivo to achieve physiological DSB repair, or that strong compensatory mechanisms exist.
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Common and unique genetic interactions of the poly(ADP-ribose) polymerases PARP1 and PARP2 with DNA double-strand break repair pathways
DNA Repair, 2016Co-Authors: Rajib Ghosh, Françoise Dantzer, Sanchita Roy, Johan Kamyab, Sonia FrancoAbstract:In mammalian cells, chromatin poly(ADP-ribos)ylation (PARylation) at sites of DNA Double-Strand Breaks (DSBs) is mediated by two highly related enzymes, PARP1 and PARP2. However, enzyme-specific genetic interactions with other DSB repair factors remain largely undefined. In this context, it was previously shown that mice lacking PARP1 and H2AX, a histone variant that promotes DSB repair throughout the cell cycle, or the core nonhomologous end-joining (NHEJ) factor Ku80 are not viable, while mice lacking PARP1 and the noncore NHEJ factor DNA-PKcs are severely growth retarded and markedly lymphoma-prone. Here, we have examined the requirement for PARP2 in these backgrounds. We find that, like PARP1, PARP2 is essential for viability in mice lacking H2AX. Moreover, treatment of H2AX-deficient primary fibroblasts or B lymphocytes with PARP inhibitors leads to activation of the G2/M checkpoint and accumulation of chromatid-type breaks in a lineage- and gene-dose dependent manner. In marked contrast to PARP1, loss of PARP2 does not result in additional phenotypes in growth, development or tumorigenesis in mice lacking either Ku80 or DNA-PKcs. Altogether these findings highlight specific nonoverlapping functions of PARP1 and PARP2 at H2AX-deficient chromatin during replicative phases of the cell cycle and uncover a unique requirement for PARP1 in NHEJ-deficient cells.
Robert L Coleman - One of the best experts on this subject based on the ideXlab platform.
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rucaparib in ovarian cancer extending the use of parp inhibitors in the recurrent disease
Future Oncology, 2018Co-Authors: Graziela Dal Z Molin, Shannon Neville Westin, Robert L ColemanAbstract:Rucaparib is a potent inhibitor of poly (ADP-ribose) polymerase (PARP) PARP1, PARP2 and PARP3, and to a lesser extent, PARP4, PARP10, PARP12, PARP15 and PARP16. Study 10 and ARIEL2 evaluated the use of rucaparib as treatment in patients with recurrent high-grade ovarian carcinoma and resulting in approval of rucaparib for patients with both germline and somatic BRCA mutation. Data from the Phase III trial ARIEL3 led to approval in platinum-sensitive disease as maintenance. This article reviews the efficacy, safety, pharmacokinetics and pharmacodynamics of rucaparib as well as future and ongoing trials.
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Rucaparib in ovarian cancer: an update on safety, efficacy and place in therapy:
Therapeutic Advances in Medical Oncology, 2018Co-Authors: Graziela Z Dal Molin, Kohei Omatsu, Anil K Sood, Robert L ColemanAbstract:Rucaparib is a poly (ADP-ribose) polymerase (PARP) inhibitor and potent inhibitor of PARP1, PARP2 and PARP3 enzymes. Phase II and III trials have documented that rucaparib has single-agent antitumo...
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rucaparib in ovarian cancer an update on safety efficacy and place in therapy
Therapeutic Advances in Medical Oncology, 2018Co-Authors: Graziela Dal Z Molin, Kohei Omatsu, Anil K Sood, Robert L ColemanAbstract:Rucaparib is a poly (ADP-ribose) polymerase (PARP) inhibitor and potent inhibitor of PARP1, PARP2 and PARP3 enzymes. Phase II and III trials have documented that rucaparib has single-agent antitumor activity in patients with high-grade ovarian carcinoma, with both BRCA-mutated (germline and somatic) and with homologous recombination deficiency (HRD). Rucaparib as a maintenance treatment showed increased progression-free survival in patients with ovarian carcinoma who achieved a response to platinum-based chemotherapy, with an acceptable safety profile. The approval of this drug, along with the companion diagnostic FoundationFocus CDxBRCA test represents an important new therapeutic option in the treatment of ovarian cancer. This article reviews the mechanisms of action, safety, pharmacokinetics and pharmacodynamics and indications for use of rucaparib as well as future trials.
M. M. Kutuzov - One of the best experts on this subject based on the ideXlab platform.
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The contribution of PARP1, PARP2 and poly(ADP-ribosyl)ation to base excision repair in the nucleosomal context
Scientific reports, 2021Co-Authors: M. M. Kutuzov, S. N. Khodyreva, I. A. Vasil’eva, E. A. Belousova, T. A. Kurgina, A.a. Ukraintsev, O. I. LavrikAbstract:The regulation of repair processes including base excision repair (BER) in the presence of DNA damage is implemented by a cellular signal: poly(ADP-ribosyl)ation (PARylation), which is catalysed by PARP1 and PARP2. Despite ample studies, it is far from clear how BER is regulated by PARPs and how the roles are distributed between the PARPs. Here, we investigated the effects of PARP1, PARP2 and PARylation on activities of the main BER enzymes (APE1, DNA polymerase β [Polβ] and DNA ligase IIIα [LigIIIα]) in combination with BER scaffold protein XRCC1 in the nucleosomal context. We constructed nucleosome core particles with midward- or outward-oriented damage. It was concluded that in most cases, the presence of PARP1 leads to the suppression of the activities of APE1, Polβ and to a lesser extent LigIIIα. PARylation by PARP1 attenuated this effect to various degrees depending on the enzyme. PARP2 had an influence predominantly on the last stage of BER: DNA sealing. Nonetheless, PARylation by PARP2 led to Polβ inhibition and to significant stimulation of LigIIIα activities in a NAD+-dependent manner. On the basis of the obtained and literature data, we suggest a hypothetical model of the contribution of PARP1 and PARP2 to BER.
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The contribution of PARP1, PARP2 and poly(ADP-ribosyl)ation to base excision repair in the nucleosomal context
2020Co-Authors: M. M. Kutuzov, S. N. Khodyreva, I. A. Vasil’eva, E. A. Belousova, T. A. Kurgina, A.a. Ukraintsev, O. I. LavrikAbstract:The repair processes regulation including base excision repair (BER) is implemented by a cellular signal PARylation catalysed by PARP1 and PARP2. Despite intensive studies, it is far from clear how BER is regulated by PARPs and how the roles are distributed between the PARPs. Here, we investigated the effects of PARP1, PARP2 and PARylation on activities of the main BER enzymes (APE1, Polbeta and LigIIIalfa) in combination with XRCC1 in the nucleosomal context. We constructed nucleosomes with midward- or outward-oriented damage. It was concluded that in most cases, the presence of PARP1 leads to the suppression of the activities of APE1, Polbeta, and to a lesser extent LigIIIalfa. PARylation by PARP1 attenuated this effect to various degrees. PARP2 had an influence predominantly on the last stage of BER: DNA sealing. Nonetheless, PARylation by PARP2 led to Polbeta inhibition and to significant stimulation of LigIIIalfa activities in a NAD+-dependent manner.
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Impact of PARP1, PARP2 & PARP3 on the Base Excision Repair of Nucleosomal DNA.
Advances in experimental medicine and biology, 2020Co-Authors: M. M. Kutuzov, Ekaterina A Belousova, Ekaterina S Ilina, O. I. LavrikAbstract:DNA is constantly attacked by different damaging agents; therefore, it requires frequent repair. On the one hand, the base excision repair (BER) system is responsible for the repair of the most frequent DNA lesions. On the other hand, the formation of poly(ADP-ribose) is one of the main DNA damage response reactions that is catalysed by members of the PARP family. PARP1, which belongs to the PARP family and performs approximately 90% of PAR synthesis in cells, could be considered a main regulator of the BER process. Most of the experimental data concerning BER investigation have been obtained using naked DNA. However, in the context of the eukaryotic cell, DNA is compacted in the nucleus, and the lowest compaction level is represented by the nucleosome. Thus, the organization of DNA into the nucleosome impacts the DNA-protein interactions that are involved in BER processes. Poly(ADP-ribosyl)ation (PARylation) is thought to regulate the initiation of the BER process at the chromatin level. In this review, we focus on the mechanisms involved in BER in the nucleosomal context and the potential effect of PARylation, which is catalysed by DNA-dependent PARP1, PARP2 and PARP3 proteins, on this process.
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impact of parp1 PARP2 parp3 on the base excision repair of nucleosomal dna
Advances in Experimental Medicine and Biology, 2020Co-Authors: M. M. Kutuzov, Ekaterina A Belousova, Ekaterina S Ilina, O. I. LavrikAbstract:DNA is constantly attacked by different damaging agents; therefore, it requires frequent repair. On the one hand, the base excision repair (BER) system is responsible for the repair of the most frequent DNA lesions. On the other hand, the formation of poly(ADP-ribose) is one of the main DNA damage response reactions that is catalysed by members of the PARP family. PARP1, which belongs to the PARP family and performs approximately 90% of PAR synthesis in cells, could be considered a main regulator of the BER process. Most of the experimental data concerning BER investigation have been obtained using naked DNA. However, in the context of the eukaryotic cell, DNA is compacted in the nucleus, and the lowest compaction level is represented by the nucleosome. Thus, the organization of DNA into the nucleosome impacts the DNA-protein interactions that are involved in BER processes. Poly(ADP-ribosyl)ation (PARylation) is thought to regulate the initiation of the BER process at the chromatin level. In this review, we focus on the mechanisms involved in BER in the nucleosomal context and the potential effect of PARylation, which is catalysed by DNA-dependent PARP1, PARP2 and PARP3 proteins, on this process.
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A Single-Molecule Atomic Force Microscopy Study of PARP1 and PARP2 Recognition of Base Excision Repair DNA Intermediates
Journal of molecular biology, 2019Co-Authors: Maria V. Sukhanova, M. M. Kutuzov, Sanae Abrakhi, Vandana Joshi, David Pastre, Patrick Curmi, Loic Hamon, Ioana Dobra, O. I. LavrikAbstract:Nuclear poly(ADP-ribose) polymerases 1 and 2 (PARP1 and PARP2) catalyze the synthesis of poly(ADP-ribose) (PAR) and use NAD+ as a substrate for the polymer synthesis. Both PARP1 and PARP2 are involved in DNA damage response pathways and function as sensors of DNA breaks, including temporary single-strand breaks formed during DNA repair. Consistently, with a role in DNA repair, PARP activation requires its binding to a damaged DNA site, which initiates PAR synthesis. Here we use atomic force microscopy to characterize at the single-molecule level the interaction of PARP1 and PARP2 with long DNA substrates containing a single damage site and representing intermediates of the short-patch base excision repair (BER) pathway. We demonstrated that PARP1 has higher affinity for early intermediates of BER than PARP2, whereas both PARPs efficiently interact with the nick and may contribute to regulation of the final ligation step. The binding of a DNA repair intermediate by PARPs involved a PARP monomer or dimer depending on the type of DNA damage. PARP dimerization influences the affinity of these proteins to DNA and affects their enzymatic activity: the dimeric form is more effective in PAR synthesis in the case of PARP2 but is less effective in the case of PARP1. PARP2 suppresses PAR synthesis catalyzed by PARP1 after single-strand breaks formation. Our study suggests that the functions of PARP1 and PARP2 overlap in BER after a site cleavage and provides evidence for a role of PARP2 in the regulation of PARP1 activity.
H Schuler - One of the best experts on this subject based on the ideXlab platform.
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Correction to "Structural Basis for Potency and Promiscuity in Poly(ADP-ribose) Polymerase (PARP) and Tankyrase Inhibitors".
Journal of medicinal chemistry, 2019Co-Authors: A G Thorsell, Michael S. Cohen, T Ekblad, Tobias Karlberg, A F Pinto, Lionel Tresaugues, M Moche, Mirjam Löw, H SchulerAbstract:Selective inhibitors could help unveil the mechanisms by which inhibition of poly(ADP-ribose) polymerases (PARPs) elicits clinical benefits in cancer therapy. We profiled 10 clinical PARP inhibitors and commonly used research tools for their inhibition of multiple PARP enzymes. We also determined crystal structures of these compounds bound to PARP1 or PARP2. Veliparib and niraparib are selective inhibitors of PARP1 and PARP2; olaparib, rucaparib, and talazoparib are more potent inhibitors of PARP1 but are less selective. PJ34 and UPF1069 are broad PARP inhibitors; PJ34 inserts a flexible moiety into hydrophobic subpockets in various ADP-ribosyltransferases. XAV939 is a promiscuous tankyrase inhibitor and a potent inhibitor of PARP1 in vitro and in cells, whereas IWR1 and AZ-6102 are tankyrase selective. Our biochemical and structural analysis of PARP inhibitor potencies establishes a molecular basis for either selectivity or promiscuity and provides a benchmark for experimental design in assessment of PARP inhibitor effects
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Selectivity profile of the poly(ADP-ribose) polymerase (PARP) inhibitor, A-966492
2017Co-Authors: A G Thorsell, H SchulerAbstract:Among the clinical inhibitors of poly(ADP-ribose) polymerases (PARPs) and the commonly used PARP research tool compounds, veliparib and niraparib were recently identified as the most selective inhibitors of PARP1 and PARP2. We characterized the potency of A-966492, a PARP inhibitor with a chemical structure similar to veliparib and niraparib, in in vitro inhibition experiments of six PARP family enzymes. We find that the selectivity of A-966492 for PARP1 and PARP2 is intermediate between veliparib and niraparib.
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structural basis for potency and promiscuity in poly adp ribose polymerase parp and tankyrase inhibitors
Journal of Medicinal Chemistry, 2017Co-Authors: A G Thorsell, Michael S. Cohen, T Ekblad, Tobias Karlberg, A F Pinto, Lionel Tresaugues, M Moche, H SchulerAbstract:Selective inhibitors could help unveil the mechanisms by which inhibition of poly(ADP-ribose) polymerases (PARPs) elicits clinical benefits in cancer therapy. We profiled 10 clinical PARP inhibitors and commonly used research tools for their inhibition of multiple PARP enzymes. We also determined crystal structures of these compounds bound to PARP1 or PARP2. Veliparib and niraparib are selective inhibitors of PARP1 and PARP2; olaparib, rucaparib, and talazoparib are more potent inhibitors of PARP1 but are less selective. PJ34 and UPF1069 are broad PARP inhibitors; PJ34 inserts a flexible moiety into hydrophobic subpockets in various ADP-ribosyltransferases. XAV939 is a promiscuous tankyrase inhibitor and a potent inhibitor of PARP1 in vitro and in cells, whereas IWR1 and AZ-6102 are tankyrase selective. Our biochemical and structural analysis of PARP inhibitor potencies establishes a molecular basis for either selectivity or promiscuity and provides a benchmark for experimental design in assessment of PAR...