Poly [ADP-ribose] polymerase 2 is an enzyme that in humans is encoded by the PARP2 gene. [5] [6] [7] It is one of the PARP family of enzymes.
This gene encodes poly(ADP-ribosyl)transferase-like 2 protein, which contains a catalytic domain and is capable of catalyzing a poly(ADP-ribosyl)ation reaction. This protein has a catalytic domain which is homologous to that of poly (ADP-ribosyl) transferase, but lacks an N-terminal DNA binding domain which activates the C-terminal catalytic domain of poly (ADP-ribosyl) transferase. The basic residues within the N-terminal region of this protein may bear potential DNA-binding properties, and may be involved in the nuclear and/or nucleolar targeting of the protein. Two alternatively spliced transcript variants encoding distinct isoforms have been found. [7]
In the plant species Arabidopsis thaliana, PARP2 plays more significant roles than PARP1 in protective responses to DNA damage and bacterial pathogenesis. [8] The plant PARP2 carries N-terminal SAP DNA binding motifs rather than the Zn-finger DNA binding motifs of plant and animal PARP1 proteins. [8]
Some PARP inhibitor anti-cancer drugs (primarily aimed at PARP1) also inhibit PARP2, e.g. niraparib.
PARP2 has been shown to interact with XRCC1. [9]
Poly (ADP-ribose) polymerase (PARP) is a family of proteins involved in a number of cellular processes such as DNA repair, genomic stability, and programmed cell death.
DNA repair protein XRCC1, also known as X-ray repair cross-complementing protein 1, is a protein that in humans is encoded by the XRCC1 gene. XRCC1 is involved in DNA repair, where it complexes with DNA ligase III.
ADP-ribosylation is the addition of one or more ADP-ribose moieties to a protein. It is a reversible post-translational modification that is involved in many cellular processes, including cell signaling, DNA repair, gene regulation and apoptosis. Improper ADP-ribosylation has been implicated in some forms of cancer. It is also the basis for the toxicity of bacterial compounds such as cholera toxin, diphtheria toxin, and others.
Poly [ADP-ribose] polymerase 1 (PARP-1) also known as NAD+ ADP-ribosyltransferase 1 or poly[ADP-ribose] synthase 1 is an enzyme that in humans is encoded by the PARP1 gene. It is the most abundant of the PARP family of enzymes, accounting for 90% of the NAD+ used by the family. PARP1 is mostly present in cell nucleus, but cytosolic fraction of this protein was also reported.
Tankyrase, also known as tankyrase 1, is an enzyme that in humans is encoded by the TNKS gene. It inhibits the binding of TERF1 to telomeric DNA. Tankyrase attracts substantial interest in cancer research through its interaction with AXIN1 and AXIN2, which are negative regulators of pro-oncogenic β-catenin signaling. Importantly, activity in the β-catenin destruction complex can be increased by tankyrase inhibitors and thus such inhibitors are a potential therapeutic option to reduce the growth of β-catenin-dependent cancers.
Nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) is an enzyme that in humans is encoded by the nmnat1 gene. It is a member of the nicotinamide-nucleotide adenylyltransferases (NMNATs) which catalyze nicotinamide adenine dinucleotide (NAD) synthesis.
Poly [ADP-ribose] polymerase 4 is an enzyme that in humans is encoded by the PARP4 gene.
Poly [ADP-ribose] polymerase 3 is an enzyme that in humans is encoded by the PARP3 gene.
Tankyrase-2 is an enzyme that in humans is encoded by the TNKS2 gene.
(ADP-ribosyl)hydrolase 3 (ARH3) is an enzyme that in humans is encoded by the ADPRHL2 gene (also called ADPRS). This enzyme reverses the proteins’ post-translational addition of ADP-ribose to serine residues as part of the DNA damage response The enzyme is also known to cleave poly(ADP-ribose) polymers, 1''-O-acetyl-ADP-ribose and alpha-NAD+
Poly [ADP-ribose] polymerase 8 is an enzyme that in humans is encoded by the PARP8 gene.
TCDD-inducible poly [ADP-ribose] polymerase is an enzyme that in humans is encoded by the TIPARP gene.
Poly [ADP-ribose] polymerase 10 is an enzyme that in humans is encoded by the PARP10 gene.
PARP inhibitors are a group of pharmacological inhibitors of the enzyme poly ADP ribose polymerase (PARP).
In molecular biology, the (ADP-ribosyl)hydrolase (ARH) family contains enzymes which catalyses the hydrolysis of ADP-ribosyl modifications from proteins, nucleic acids and small molecules.
In molecular biology, the Macro domain or A1pp domain is a module of about 180 amino acids which can bind ADP-ribose, an NAD metabolite, or related ligands. Binding to ADP-ribose can be either covalent or non-covalent: in certain cases it is believed to bind non-covalently, while in other cases it appears to bind both non-covalently through a zinc finger motif, and covalently through a separate region of the protein.
DNA ligase 3 is an enzyme that, in humans, is encoded by the LIG3 gene. The human LIG3 gene encodes ATP-dependent DNA ligases that seal interruptions in the phosphodiester backbone of duplex DNA.
(ADP-ribosyl)hydrolase 1, also termed [Protein ADP-ribosylarginine] hydrolase and protein-Nω-(ADP-D-ribosyl)-L-arginine ADP-ribosylhydrolase (EC 3.2.2.19), is an enzyme that in humans is encoded by the ADPRH gene. This enzyme is a specific mono(ADP-ribosyl)hydrolase that catalyses the removal of an ADP-ribosyl modification from target arginine residues of protein substrates. The chemical reactions can formally be described as follows:
DNA polymerase alpha subunit 2 is an enzyme that in humans is encoded by the POLA2 gene.
Parthanatos is a form of programmed cell death that is distinct from other cell death processes such as necrosis and apoptosis. While necrosis is caused by acute cell injury resulting in traumatic cell death and apoptosis is a highly controlled process signalled by apoptotic intracellular signals, parthanatos is caused by the accumulation of Poly(ADP ribose) (PAR) and the nuclear translocation of apoptosis-inducing factor (AIF) from mitochondria. Parthanatos is also known as PARP-1 dependent cell death. PARP-1 mediates parthanatos when it is over-activated in response to extreme genomic stress and synthesizes PAR which causes nuclear translocation of AIF. Parthanatos is involved in diseases that afflict hundreds of millions of people worldwide. Well known diseases involving parthanatos include Parkinson's disease, stroke, heart attack, and diabetes. It also has potential use as a treatment for ameliorating disease and various medical conditions such as diabetes and obesity.