Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 8.313
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Cell ; 184(17): 4531-4546.e26, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34314702

RESUMO

Defects in translation lead to changes in the expression of proteins that can serve as drivers of cancer formation. Here, we show that cytosolic NAD+ synthesis plays an essential role in ovarian cancer by regulating translation and maintaining protein homeostasis. Expression of NMNAT-2, a cytosolic NAD+ synthase, is highly upregulated in ovarian cancers. NMNAT-2 supports the catalytic activity of the mono(ADP-ribosyl) transferase (MART) PARP-16, which mono(ADP-ribosyl)ates (MARylates) ribosomal proteins. Depletion of NMNAT-2 or PARP-16 leads to inhibition of MARylation, increased polysome association and enhanced translation of specific mRNAs, aggregation of their translated protein products, and reduced growth of ovarian cancer cells. Furthermore, MARylation of the ribosomal proteins, such as RPL24 and RPS6, inhibits polysome assembly by stabilizing eIF6 binding to ribosomes. Collectively, our results demonstrate that ribosome MARylation promotes protein homeostasis in cancers by fine-tuning the levels of protein synthesis and preventing toxic protein aggregation.


Assuntos
ADP-Ribosilação , Neoplasias Ovarianas/metabolismo , Biossíntese de Proteínas , Proteostase , Ribossomos/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Estresse do Retículo Endoplasmático , Tubas Uterinas/metabolismo , Feminino , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , NAD/metabolismo , Nicotinamida-Nucleotídeo Adenililtransferase , Conformação de Ácido Nucleico , Neoplasias Ovarianas/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Polirribossomos/metabolismo , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/metabolismo
2.
Nat Rev Mol Cell Biol ; 22(12): 796-814, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34429537

RESUMO

The protein kinase ataxia telangiectasia mutated (ATM) is a master regulator of double-strand DNA break (DSB) signalling and stress responses. For three decades, ATM has been investigated extensively to elucidate its roles in the DNA damage response (DDR) and in the pathogenesis of ataxia telangiectasia (A-T), a human neurodegenerative disease caused by loss of ATM. Although hundreds of proteins have been identified as ATM phosphorylation targets and many important roles for this kinase have been identified, it is still unclear how ATM deficiency leads to the early-onset cerebellar degeneration that is common in all individuals with A-T. Recent studies suggest the existence of links between ATM deficiency and other cerebellum-specific neurological disorders, as well as the existence of broader similarities with more common neurodegenerative disorders. In this Review, we discuss recent structural insights into ATM regulation, and possible aetiologies of A-T phenotypes, including reactive oxygen species, mitochondrial dysfunction, alterations in transcription, R-loop metabolism and alternative splicing, defects in cellular proteostasis and metabolism, and potential pathogenic roles for hyper-poly(ADP-ribosyl)ation.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Ataxia Telangiectasia/metabolismo , Doenças Neurodegenerativas/metabolismo , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/patologia , Proteínas Mutadas de Ataxia Telangiectasia/química , Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Reparo do DNA , Homeostase , Humanos , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Oxirredução , Fosforilação , Poli(ADP-Ribose) Polimerases/metabolismo , RNA/metabolismo
3.
Mol Cell ; 84(3): 429-446.e17, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38215753

RESUMO

Nucleosomes, the basic structural units of chromatin, hinder recruitment and activity of various DNA repair proteins, necessitating modifications that enhance DNA accessibility. Poly(ADP-ribosyl)ation (PARylation) of proteins near damage sites is an essential initiation step in several DNA-repair pathways; however, its effects on nucleosome structural dynamics and organization are unclear. Using NMR, cryoelectron microscopy (cryo-EM), and biochemical assays, we show that PARylation enhances motions of the histone H3 tail and DNA, leaving the configuration of the core intact while also stimulating nuclease digestion and ligation of nicked nucleosomal DNA by LIG3. PARylation disrupted interactions between nucleosomes, preventing self-association. Addition of LIG3 and XRCC1 to PARylated nucleosomes generated condensates that selectively partition DNA repair-associated proteins in a PAR- and phosphorylation-dependent manner in vitro. Our results establish that PARylation influences nucleosomes across different length scales, extending from the atom-level motions of histone tails to the mesoscale formation of condensates with selective compositions.


Assuntos
Nucleossomos , Poli ADP Ribosilação , Nucleossomos/genética , Poli ADP Ribosilação/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Microscopia Crioeletrônica , Condensados Biomoleculares , Reparo do DNA , Histonas/genética , Histonas/metabolismo , DNA/genética , DNA/metabolismo , Dano ao DNA , Poli(ADP-Ribose) Polimerase-1/metabolismo
5.
Mol Cell ; 84(20): 3916-3931.e7, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39383878

RESUMO

Poly (ADP-ribose) polymerase (PARP) 1 and 2 enzymatic inhibitors (PARPi) are promising cancer treatments. But recently, their use has been hindered by unexplained severe anemia and treatment-related leukemia. In addition to enzymatic inhibition, PARPi also trap PARP1 and 2 at DNA lesions. Here we report that, unlike Parp2-/- mice, which develop normally, mice expressing catalytically inactive Parp2 (E534A and Parp2EA/EA) succumb to Tp53- and Chk2-dependent erythropoietic failure in utero, mirroring Lig1-/- mice. While DNA damage mainly activates PARP1, we demonstrate that DNA replication activates PARP2 robustly. PARP2 is selectively recruited and activated by 5'-phosphorylated nicks (5'p-nicks), including those between Okazaki fragments, resolved by ligase 1 (Lig1) and Lig3. Inactive PARP2, but not its active form or absence, impedes Lig1- and Lig3-mediated ligation, causing dose-dependent replication fork collapse, which is detrimental to erythroblasts with ultra-fast forks. This PARylation-dependent structural function of PARP2 at 5'p-nicks explains the detrimental effects of PARP2 inactivation on erythropoiesis, shedding light on PARPi-induced anemia and the selection for TP53/CHK2 loss.


Assuntos
Anemia , Quinase do Ponto de Checagem 2 , Replicação do DNA , Eritroblastos , Poli(ADP-Ribose) Polimerases , Proteína Supressora de Tumor p53 , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Eritroblastos/metabolismo , Eritroblastos/efeitos dos fármacos , Camundongos , Replicação do DNA/efeitos dos fármacos , Anemia/genética , Anemia/induzido quimicamente , Anemia/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Quinase do Ponto de Checagem 2/metabolismo , Quinase do Ponto de Checagem 2/genética , Camundongos Knockout , Dano ao DNA , Eritropoese/efeitos dos fármacos , Eritropoese/genética , Humanos , DNA Ligase Dependente de ATP/genética , DNA Ligase Dependente de ATP/metabolismo , Camundongos Endogâmicos C57BL , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
6.
Annu Rev Biochem ; 85: 431-54, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-26844395

RESUMO

Recent developments indicate that macrodomains, an ancient and diverse protein domain family, are key players in the recognition, interpretation, and turnover of ADP-ribose (ADPr) signaling. Crucial to this is the ability of macrodomains to recognize ADPr either directly, in the form of a metabolic derivative, or as a modification covalently bound to proteins. Thus, macrodomains regulate a wide variety of cellular and organismal processes, including DNA damage repair, signal transduction, and immune response. Their importance is further indicated by the fact that dysregulation or mutation of a macrodomain is associated with several diseases, including cancer, developmental defects, and neurodegeneration. In this review, we summarize the current insights into macrodomain evolution and how this evolution influenced their structural and functional diversification. We highlight some aspects of macrodomain roles in pathobiology as well as their emerging potential as therapeutic targets.


Assuntos
Reparo do DNA , Proteínas de Escherichia coli/química , Neoplasias/enzimologia , Poli(ADP-Ribose) Polimerases/química , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/química , Viroses/enzimologia , Adenosina Difosfato Ribose/química , Adenosina Difosfato Ribose/metabolismo , Animais , Dano ao DNA , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Evolução Molecular , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Família Multigênica , Neoplasias/química , Neoplasias/genética , Neoplasias/patologia , Filogenia , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Domínios Proteicos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Homologia Estrutural de Proteína , Viroses/genética , Viroses/patologia , Viroses/virologia
8.
Mol Cell ; 83(10): 1552-1572, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37119811

RESUMO

PARPs catalyze ADP-ribosylation-a post-translational modification that plays crucial roles in biological processes, including DNA repair, transcription, immune regulation, and condensate formation. ADP-ribosylation can be added to a wide range of amino acids with varying lengths and chemical structures, making it a complex and diverse modification. Despite this complexity, significant progress has been made in developing chemical biology methods to analyze ADP-ribosylated molecules and their binding proteins on a proteome-wide scale. Additionally, high-throughput assays have been developed to measure the activity of enzymes that add or remove ADP-ribosylation, leading to the development of inhibitors and new avenues for therapy. Real-time monitoring of ADP-ribosylation dynamics can be achieved using genetically encoded reporters, and next-generation detection reagents have improved the precision of immunoassays for specific forms of ADP-ribosylation. Further development and refinement of these tools will continue to advance our understanding of the functions and mechanisms of ADP-ribosylation in health and disease.


Assuntos
ADP-Ribosilação , Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/metabolismo , Processamento de Proteína Pós-Traducional , Adenosina Difosfato Ribose/metabolismo
9.
Nature ; 628(8007): 433-441, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509368

RESUMO

An important advance in cancer therapy has been the development of poly(ADP-ribose) polymerase (PARP) inhibitors for the treatment of homologous recombination (HR)-deficient cancers1-6. PARP inhibitors trap PARPs on DNA. The trapped PARPs are thought to block replisome progression, leading to formation of DNA double-strand breaks that require HR for repair7. Here we show that PARP1 functions together with TIMELESS and TIPIN to protect the replisome in early S phase from transcription-replication conflicts. Furthermore, the synthetic lethality of PARP inhibitors with HR deficiency is due to an inability to repair DNA damage caused by transcription-replication conflicts, rather than by trapped PARPs. Along these lines, inhibiting transcription elongation in early S phase rendered HR-deficient cells resistant to PARP inhibitors and depleting PARP1 by small-interfering RNA was synthetic lethal with HR deficiency. Thus, inhibiting PARP1 enzymatic activity may suffice for treatment efficacy in HR-deficient settings.


Assuntos
Replicação do DNA , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases , Transcrição Gênica , Humanos , Quebras de DNA de Cadeia Dupla , Replicação do DNA/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Reparo de DNA por Recombinação , Fase S , Transcrição Gênica/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Poli(ADP-Ribose) Polimerase-1/metabolismo
10.
Mol Cell ; 82(7): 1297-1312.e8, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35219381

RESUMO

Synthetic lethality through combinatorial targeting DNA damage response (DDR) pathways provides exciting anticancer therapeutic benefit. Currently, the long noncoding RNAs (lncRNAs) have been implicated in tumor drug resistance; however, their potential significance in DDR is still largely unknown. Here, we report that a human lncRNA, CTD-2256P15.2, encodes a micropeptide, named PAR-amplifying and CtIP-maintaining micropeptide (PACMP), with a dual function to maintain CtIP abundance and promote poly(ADP-ribosyl)ation. PACMP not only prevents CtIP from ubiquitination through inhibiting the CtIP-KLHL15 association but also directly binds DNA damage-induced poly(ADP-ribose) chains to enhance PARP1-dependent poly(ADP-ribosyl)ation. Targeting PACMP alone inhibits tumor growth by causing a synthetic lethal interaction between CtIP and PARP inhibitions and confers sensitivity to PARP/ATR/CDK4/6 inhibitors, ionizing radiation, epirubicin, and camptothecin. Our findings reveal that a lncRNA-derived micropeptide regulates cancer progression and drug resistance by modulating DDR, whose inhibition could be employed to augment the existing anticancer therapeutic strategies.


Assuntos
Endodesoxirribonucleases , Neoplasias , Peptídeos , Poli ADP Ribosilação , RNA Longo não Codificante , Reparo do DNA , Endodesoxirribonucleases/metabolismo , Humanos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Peptídeos/farmacologia , Poli Adenosina Difosfato Ribose/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
Genes Dev ; 36(9-10): 601-617, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35654456

RESUMO

The differentiation of embryonic stem cells (ESCs) into a lineage-committed state is a dynamic process involving changes in cellular metabolism, epigenetic modifications, post-translational modifications, gene expression, and RNA processing. Here we integrated data from metabolomic, proteomic, and transcriptomic assays to characterize how alterations in NAD+ metabolism during the differentiation of mouse ESCs lead to alteration of the PARP1-mediated ADP-ribosylated (ADPRylated) proteome and mRNA isoform specialization. Our metabolomic analyses indicate that mESCs use distinct NAD+ biosynthetic pathways in different cell states: the de novo pathway in the pluripotent state, and the salvage and Preiss-Handler pathways as differentiation progresses. We observed a dramatic induction of PARP1 catalytic activity driven by enhanced nuclear NAD+ biosynthesis during the early stages of mESC differentiation (e.g., within 12 h of LIF removal). PARP1-modified proteins in mESCs are enriched for biological processes related to stem cell maintenance, transcriptional regulation, and RNA processing. The PARP1 substrates include core spliceosome components, such as U2AF35 and U2AF65, whose splicing functions are modulated by PARP1-mediated site-specific ADP-ribosylation. Finally, we observed that splicing is dysregulated genome-wide in Parp1 knockout mESCs. Together, these results demonstrate a role for the NAD+-PARP1 axis in the maintenance of mESC state, specifically in the splicing program during differentiation.


Assuntos
NAD , Poli(ADP-Ribose) Polimerases , ADP-Ribosilação , Animais , Células-Tronco Embrionárias/metabolismo , Camundongos , NAD/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteômica
12.
Cell ; 157(4): 882-896, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24813611

RESUMO

Mitochondrial dysfunction is a common feature in neurodegeneration and aging. We identify mitochondrial dysfunction in xeroderma pigmentosum group A (XPA), a nucleotide excision DNA repair disorder with severe neurodegeneration, in silico and in vivo. XPA-deficient cells show defective mitophagy with excessive cleavage of PINK1 and increased mitochondrial membrane potential. The mitochondrial abnormalities appear to be caused by decreased activation of the NAD(+)-SIRT1-PGC-1α axis triggered by hyperactivation of the DNA damage sensor PARP-1. This phenotype is rescued by PARP-1 inhibition or by supplementation with NAD(+) precursors that also rescue the lifespan defect in xpa-1 nematodes. Importantly, this pathogenesis appears common to ataxia-telangiectasia and Cockayne syndrome, two other DNA repair disorders with neurodegeneration, but absent in XPC, a DNA repair disorder without neurodegeneration. Our findings reveal a nuclear-mitochondrial crosstalk that is critical for the maintenance of mitochondrial health.


Assuntos
Mitofagia , Poli(ADP-Ribose) Polimerases/metabolismo , Sirtuína 1/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Xeroderma Pigmentoso/fisiopatologia , Envelhecimento , Animais , Apoptose , Autofagia , Caenorhabditis elegans , Linhagem Celular , Humanos , Canais Iônicos/metabolismo , Camundongos , Proteínas Mitocondriais/metabolismo , Proteínas Quinases/metabolismo , Ratos , Proteína Desacopladora 2 , Xeroderma Pigmentoso/metabolismo
13.
Mol Cell ; 81(7): 1367-1369, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33798413

RESUMO

Mutations in ataxia telangiectasia mutated (ATM) kinase lead to cerebellar neurodegeneration. In this issue of Molecular Cell, Lee et al. (2021) revealed how transcription-induced reactive oxygen species and DNA-RNA hybrids activate PARP enzymes, generating the nucleic acid poly-ADP-ribose, which promotes the accumulation of protein aggregates in A-T-like disorders.


Assuntos
Ataxia Telangiectasia , Ácidos Nucleicos , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Poli(ADP-Ribose) Polimerase-1 , Poli ADP Ribosilação , Poli(ADP-Ribose) Polimerases/metabolismo , Agregados Proteicos , Proteostase , Proteínas Supressoras de Tumor/genética
14.
Mol Cell ; 81(14): 3018-3030.e5, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34102106

RESUMO

Mammalian DNA base excision repair (BER) is accelerated by poly(ADP-ribose) polymerases (PARPs) and the scaffold protein XRCC1. PARPs are sensors that detect single-strand break intermediates, but the critical role of XRCC1 during BER is unknown. Here, we show that protein complexes containing DNA polymerase ß and DNA ligase III that are assembled by XRCC1 prevent excessive engagement and activity of PARP1 during BER. As a result, PARP1 becomes "trapped" on BER intermediates in XRCC1-deficient cells in a manner similar to that induced by PARP inhibitors, including in patient fibroblasts from XRCC1-mutated disease. This excessive PARP1 engagement and trapping renders BER intermediates inaccessible to enzymes such as DNA polymerase ß and impedes their repair. Consequently, PARP1 deletion rescues BER and resistance to base damage in XRCC1-/- cells. These data reveal excessive PARP1 engagement during BER as a threat to genome integrity and identify XRCC1 as an "anti-trapper" that prevents toxic PARP1 activity.


Assuntos
Reparo do DNA/genética , DNA/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/metabolismo , Animais , Linhagem Celular , Quebras de DNA de Cadeia Simples , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , DNA Ligase Dependente de ATP/metabolismo , DNA Polimerase beta/metabolismo , Reparo do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Ligação Proteica/efeitos dos fármacos
15.
Mol Cell ; 81(22): 4591-4604.e8, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34592134

RESUMO

Protein ADP-ribosylation is a reversible post-translational modification that transfers ADP-ribose from NAD+ onto acceptor proteins. Poly(ADP-ribosyl)ation (PARylation), catalyzed by poly(ADP-ribose) polymerases (PARPs) and poly(ADP-ribose) glycohydrolases (PARGs), which remove the modification, regulates diverse cellular processes. However, the chemistry and physiological functions of mono(ADP-ribosyl)ation (MARylation) remain elusive. Here, we report that Arabidopsis zinc finger proteins SZF1 and SZF2, key regulators of immune gene expression, are MARylated by the noncanonical ADP-ribosyltransferase SRO2. Immune elicitation promotes MARylation of SZF1/SZF2 via dissociation from PARG1, which has an unconventional activity in hydrolyzing both poly(ADP-ribose) and mono(ADP-ribose) from acceptor proteins. MARylation antagonizes polyubiquitination of SZF1 mediated by the SH3 domain-containing proteins SH3P1/SH3P2, thereby stabilizing SZF1 proteins. Our study uncovers a noncanonical ADP-ribosyltransferase mediating MARylation of immune regulators and underpins the molecular mechanism of maintaining protein homeostasis by the counter-regulation of ADP-ribosylation and polyubiquitination to ensure proper immune responses.


Assuntos
ADP-Ribosilação , Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Proteínas de Ligação a DNA/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Imunidade Vegetal , Ubiquitinação , Dedos de Zinco , ADP Ribose Transferases/metabolismo , Difosfato de Adenosina/química , Arabidopsis/metabolismo , Sistemas CRISPR-Cas , Genes de Plantas , Glicosídeo Hidrolases/metabolismo , Homeostase , Humanos , Hidrólise , Mutação , Plantas Geneticamente Modificadas , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteostase , Plântula/metabolismo , Especificidade por Substrato , Tristetraprolina/química , Técnicas do Sistema de Duplo-Híbrido , Ubiquitina/química
16.
Mol Cell ; 81(4): 767-783.e11, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33333017

RESUMO

Chromatin is a barrier to efficient DNA repair, as it hinders access and processing of certain DNA lesions. ALC1/CHD1L is a nucleosome-remodeling enzyme that responds to DNA damage, but its precise function in DNA repair remains unknown. Here we report that loss of ALC1 confers sensitivity to PARP inhibitors, methyl-methanesulfonate, and uracil misincorporation, which reflects the need to remodel nucleosomes following base excision by DNA glycosylases but prior to handover to APEX1. Using CRISPR screens, we establish that ALC1 loss is synthetic lethal with homologous recombination deficiency (HRD), which we attribute to chromosome instability caused by unrepaired DNA gaps at replication forks. In the absence of ALC1 or APEX1, incomplete processing of BER intermediates results in post-replicative DNA gaps and a critical dependence on HR for repair. Hence, targeting ALC1 alone or as a PARP inhibitor sensitizer could be employed to augment existing therapeutic strategies for HRD cancers.


Assuntos
Montagem e Desmontagem da Cromatina , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , Nucleossomos/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , DNA Helicases/genética , Replicação do DNA/efeitos dos fármacos , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/genética , Recombinação Homóloga/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Nucleossomos/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/genética
17.
EMBO J ; 43(14): 2908-2928, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834852

RESUMO

Protein ADP-ribosylation plays important but ill-defined roles in antiviral signalling cascades such as the interferon response. Several viruses of clinical interest, including coronaviruses, express hydrolases that reverse ADP-ribosylation catalysed by host enzymes, suggesting an important role for this modification in host-pathogen interactions. However, which ADP-ribosyltransferases mediate host ADP-ribosylation, what proteins and pathways they target and how these modifications affect viral infection and pathogenesis is currently unclear. Here we show that host ADP-ribosyltransferase activity induced by IFNγ signalling depends on PARP14 catalytic activity and that the PARP9/DTX3L complex is required to uphold PARP14 protein levels via post-translational mechanisms. Both the PARP9/DTX3L complex and PARP14 localise to IFNγ-induced cytoplasmic inclusions containing ADP-ribosylated proteins, and both PARP14 itself and DTX3L are likely targets of PARP14 ADP-ribosylation. We provide evidence that these modifications are hydrolysed by the SARS-CoV-2 Nsp3 macrodomain, shedding light on the intricate cross-regulation between IFN-induced ADP-ribosyltransferases and the potential roles of the coronavirus macrodomain in counteracting their activity.


Assuntos
ADP-Ribosilação , Interferon gama , Poli(ADP-Ribose) Polimerases , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Interferon gama/metabolismo , Interações Hospedeiro-Patógeno , Células HEK293 , ADP Ribose Transferases/metabolismo , ADP Ribose Transferases/genética , Processamento de Proteína Pós-Traducional , SARS-CoV-2/metabolismo , Proteínas de Neoplasias , Ubiquitina-Proteína Ligases
18.
EMBO J ; 43(14): 2929-2953, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38834853

RESUMO

PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways.


Assuntos
ADP-Ribosilação , Interferons , Poli(ADP-Ribose) Polimerases , Ubiquitina-Proteína Ligases , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Interferons/metabolismo , Ubiquitinação , Células HEK293 , SARS-CoV-2/metabolismo , Transdução de Sinais , COVID-19/virologia , COVID-19/metabolismo , Proteínas de Neoplasias
19.
Nat Immunol ; 17(6): 687-94, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27089381

RESUMO

Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that mediates the toxic activity of many environmental xenobiotics. However, its role in innate immune responses during viral infection is not fully understood. Here we demonstrate that constitutive AHR signaling negatively regulates the type I interferon (IFN-I) response during infection with various types of virus. Virus-induced IFN-ß production was enhanced in AHR-deficient cells and mice and resulted in restricted viral replication. We found that AHR upregulates expression of the ADP-ribosylase TIPARP, which in turn causes downregulation of the IFN-I response. Mechanistically, TIPARP interacted with the kinase TBK1 and suppressed its activity by ADP-ribosylation. Thus, this study reveals the physiological importance of endogenous activation of AHR signaling in shaping the IFN-I-mediated innate response and, further, suggests that the AHR-TIPARP axis is a potential therapeutic target for enhancing antiviral responses.


Assuntos
Poli(ADP-Ribose) Polimerases/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Viroses/imunologia , Animais , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Imunidade Inata , Interferon Tipo I/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Poli(ADP-Ribose) Polimerases/genética , RNA Interferente Pequeno/genética , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Ativação Transcricional , Replicação Viral
20.
Cell ; 155(1): 148-59, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24055367

RESUMO

Insulators mediate inter- and intrachromosomal contacts to regulate enhancer-promoter interactions and establish chromosome domains. The mechanisms by which insulator activity can be regulated to orchestrate changes in the function and three-dimensional arrangement of the genome remain elusive. Here, we demonstrate that Drosophila insulator proteins are poly(ADP-ribosyl)ated and that mutation of the poly(ADP-ribose) polymerase (Parp) gene impairs their function. This modification is not essential for DNA occupancy of insulator DNA-binding proteins dCTCF and Su(Hw). However, poly(ADP-ribosyl)ation of K566 in CP190 promotes protein-protein interactions with other insulator proteins, association with the nuclear lamina, and insulator activity in vivo. Consistent with these findings, the nuclear clustering of CP190 complexes is disrupted in Parp mutant cells. Importantly, poly(ADP-ribosyl)ation facilitates intrachromosomal interactions between insulator sites measured by 4C. These data suggest that the role of insulators in organizing the three-dimensional architecture of the genome may be modulated by poly(ADP-ribosyl)ation.


Assuntos
Cromossomos de Insetos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Elementos Isolantes , Poli Adenosina Difosfato Ribose/metabolismo , Animais , Diferenciação Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Mutação , Matriz Nuclear/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Cromossomos Politênicos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA