PARP2
PARP2 (poly(ADP-ribose) polymerase 2, also known as ARTD2 or ADPRTL2) is a nuclear poly-ADP-ribosyltransferase of the ARTD/PARP family. It modifies proteins with ADP-ribose and plays a key role in the repair of DNA damage. Browse Assay Genie's current range of PARP2 research reagents below, or read on for the biology behind the target.
PARP2 catalyses poly-ADP-ribosylation of proteins. It transfers the ADP-D-ribosyl group of NAD(+) to the carboxyl group of glutamate, aspartate or serine residues on target proteins, then adds further ADP-ribosyl groups to the 2'-position of the terminal adenosine, building a polymer with an average chain length of 20-30 units. PARP2 specifically mediates formation of branched poly-ADP-ribose, and branched chains are recognised by factors such as APLF. In addition to proteins, it can ADP-ribosylate DNA, acting preferentially on 5'-terminal phosphates at strand break termini in nicked duplex DNA.
In DNA repair, PARP2 recognises and binds DNA breaks within chromatin and recruits HPF1. Without HPF1 it modifies glutamate and aspartate residues; with HPF1, which completes the PARP2 active site, it switches to serine ADP-ribosylation, the primary form of protein ADP-ribosylation in response to DNA damage. Modification of targets such as histones promotes chromatin decompaction and the recruitment of repair factors, leading to repair of strand breaks. HPF1 also restricts the polymerase activity of PARP2, limiting the length of poly-ADP-ribose chains.
The PARP2 gene encodes a protein with a catalytic domain homologous to that of PARP1, but it lacks the N-terminal DNA-binding domain that activates the catalytic domain of PARP1. Basic residues in its N-terminal region may confer DNA-binding properties and may be involved in nuclear and/or nucleolar targeting. Two alternatively spliced transcript variants encoding distinct isoforms have been described. Earlier names include ADP-ribosyltransferase (NAD+; poly(ADP-ribose) polymerase)-like 2.
PARP2 binds DNA breaks within chromatin and initiates repair of double-strand breaks, making it a focus for studies of strand break signalling.
PARP2 modifies glutamate, aspartate and serine residues and forms branched poly-ADP-ribose chains, so it is used to study how ADP-ribose signals are written.
Serine ADP-ribosylation of histones by PARP2 and HPF1 promotes chromatin decompaction and recruitment of repair factors.
With a catalytic domain homologous to PARP1 but no N-terminal DNA-binding domain, PARP2 allows comparison of how family members are activated.
PARP2 is a poly-ADP-ribosyltransferase that attaches ADP-ribose chains to proteins and, in some cases, DNA. It binds DNA breaks within chromatin, recruits HPF1 and drives serine ADP-ribosylation of targets such as histones, promoting chromatin decompaction and recruitment of repair factors.
PARP2 is also called ARTD2 and ADPRTL2. Earlier names include ADP-ribosyltransferase (NAD+; poly(ADP-ribose) polymerase)-like 2 and poly (ADP-ribose) polymerase family, member 2. RefSeq reports two alternatively spliced transcript variants that encode distinct isoforms.
Both belong to the ARTD/PARP family and share a homologous catalytic domain. PARP2 lacks the N-terminal DNA-binding domain that activates the PARP1 catalytic domain, although basic residues in its N-terminus may bind DNA. A mouse ortholog, Parp2, exists; check the datasheet of any product for its validated reactivity.
Other members of the poly(ADP-ribose) polymerase family involved in ADP-ribosylation and DNA repair research.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9UGN5; product specifications from Assay Genie datasheets.