Exosome complex component Rrp42, archaea (IPR020869)

Short name: Rrp42_archaea

Overlapping homologous superfamilies

Family relationships



The archaeal exosome is a protein complex involved in the degradation and the posttranscriptional tailing of RNA [PMID: 22503705]. It degrades single-stranded RNA (ssRNA) in the 3'-5' direction, but also can catalyze the reverse reaction of adding nucleoside diphosphates to the 3'-end of RNA which has been shown to lead to the formation of poly-A-rich tails on RNA [PMID: 21713675].

Rrp42 is a major subunit of the exosome, forming part of the catalytic core and contributing to substrate selectivity [PMID: 21618872, PMID: 24789718]. Rrp42 is a member of the RNase_PH family, named after the bacterial Ribonuclease PH, a 3'-5' exoribonuclease. Structurally all members of this family form hexameric rings (trimers of dimers). In archaea, the ring is formed by three Rrp41:Rrp42 dimers. The central chamber within the ring contains three phosphorolytic active sites located in an Rrp41 pocket at the interface between Rrp42 and Rrp41. The ring is capped by three copies of Rrp4 and/or Csl4 which contain putative RNA interaction domains [PMID: 21713675, PMID: 24789718].

GO terms

Biological Process

GO:0006401 RNA catabolic process

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0000178 exosome (RNase complex)

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.