PARN
PARN (poly(A)-specific ribonuclease, also known as DAN) is a 3'-exoribonuclease that preferentially degrades the poly(A) tails of mRNAs. Removal of the poly(A) tail is often the first step in eukaryotic mRNA decay. Browse Assay Genie's current range of PARN research reagents below, or read on for the biology behind the target.
PARN is a 3'-exoribonuclease with a preference for poly(A), which allows it to degrade the poly(A) tails of mRNAs efficiently. Exonucleolytic shortening of the tail is often the first step in the decay of eukaryotic mRNAs. PARN contacts both the 3'-end poly(A) tail and the 5'-end cap structure during degradation, and the interaction with the cap is required for efficient tail removal.
Beyond general mRNA turnover, PARN is used to silence certain maternal mRNAs translationally during oocyte maturation and early embryonic development. It is also involved in nonsense-mediated mRNA decay, the selective degradation of mRNAs that contain premature stop codons. PARN contributes to the degradation of inherently unstable mRNAs carrying AU-rich elements (AREs) in their 3'-UTR, possibly through its interaction with KHSRP. It probably mediates poly(A) removal from ARE mRNAs, the first step in their destabilisation. PARN can also recognise and trim the poly(A) tails of microRNAs such as MIR21, leading to microRNA degradation, and of H/ACA box snoRNAs, leading to increased snoRNA stability.
The human PARN gene encodes a protein found in the nucleus, cytoplasm and nucleolus. It belongs to the CAF1 family and shows similarity to the RNase D family of 3'-exonucleases. HGNC places it in the PARN exonuclease family and among ribosome biogenesis factors; its previous name was poly(A)-specific ribonuclease (deadenylation nuclease), and DAN is a former symbol. Alternatively spliced transcript variants encoding different isoforms have been reported. The mouse ortholog is Parn.
PARN removes poly(A) tails, often the first step in eukaryotic mRNA decay, making it central to studies of transcript turnover.
PARN is involved in nonsense-mediated decay of mRNAs that contain premature stop codons.
PARN helps silence certain maternal mRNAs during oocyte maturation and early embryonic development.
PARN trims poly(A) tails of microRNAs such as MIR21 and H/ACA box snoRNAs, affecting microRNA degradation or snoRNA stability.
PARN is a 3'-exoribonuclease that prefers poly(A) and efficiently degrades mRNA poly(A) tails, often the first step in mRNA decay. It also acts in nonsense-mediated decay, ARE-containing mRNA destabilisation and silencing of maternal mRNAs in oocytes and early embryos.
The HGNC name is poly(A)-specific ribonuclease, previously poly(A)-specific ribonuclease (deadenylation nuclease), and DAN is a former symbol. The enzyme is classified as EC 3.1.13.4. NCBI Gene reports alternatively spliced transcript variants encoding different isoforms.
A mouse ortholog, Parn, is recorded for the human gene. PARN belongs to the CAF1 family of ribonucleases and resembles the RNase D family of 3'-exonucleases. Check the datasheet of any product for its validated reactivity.
Interaction partners and RNA substrates linked to PARN-mediated deadenylation and mRNA decay.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O95453; product specifications from Assay Genie datasheets.