This family of proteins are components of the exosome 3'->5' exoribonuclease complex. The exosome mediates degradation of unstable mRNAs that contain AU-rich elements (AREs) within their 3' untranslated regions [1].

1: AU binding proteins recruit the exosome to degrade ARE-containing mRNAs. Chen CY, Gherzi R, Ong SE, Chan EL, Raijmakers R, Pruijn GJ, Stoecklin G, Moroni C, Mann M, Karin M; Cell. 2001;107:451-464. PMID:11719186