poly(A)-specific ribonuclease PARN; polyadenylate-specific ribonuclease, deadenylating nuclease; deadenylation nuclease (PARN, DAN)

Function

• 3'-exoribonuclease
  • preference for poly(A)tails of mRNAs
  • degrades poly(A) tails.
• decay of eukaryotic mRNAs
• silencing of maternal mRNAs translationally during oocyte maturation & early embryonic development
• interacts with both the 3'poly(A) tail & the 5'cap structure during degradation
• nonsense-mediated mRNA decay
• degradation of inherently unstable mRNAs that contain AU-rich elements (AREs) in 3' untranslated regions
• exoribonuclease cleavage of poly(A) to 5'-AMP
• interacts with KHSRP
• found in mRNA decay complex

Cofactor: Mg+2

Structure

homotrimer

Compartment

• nuclear & cytoplasmic
• some nuclear fraction is nucleolar

Expression

ubiquitous

More general terms

• exoribonuclease

Component of

• mRNA decay complex

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=5073
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:5073
• OMIM: https://mirror.omim.org/entry/604212
• UniProt: http://www.uniprot.org/uniprot/O95453.html