title: RNA decay machines: deadenylation by the Ccr4-not and Pan2-Pan3 complexes.
abstract: Shortening and removal of the 3' poly(A) tail of mature mRNA by poly(A)-specific 3' exonucleases (deadenylases) is the initial and often rate-limiting step in mRNA degradation. The majority of cytoplasmic deadenylase activity is associated with the Ccr4-Not and Pan2-Pan3 complexes. Two distinct catalytic subunits, Caf1/Pop2 and Ccr4, are associated with the Ccr4-Not complex, whereas the Pan2 enzymatic subunit forms a stable complex with Pan3. In this review, we discuss the composition and activity of these two deadenylases. In addition, we comment on generic and specific mechanisms of recruitment of Ccr4-Not and Pan2-Pan3 to mRNAs. Finally, we discuss specialised and redundant functions of the deadenylases and review the importance of Ccr4-Not subunits in the regulation of physiological processes. This article is part of a Special Issue entitled: RNA Decay mechanisms.
authors: Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Halle, Germany. ewahle@biochemtech.uni-halle.de
authors: Elmar
authors: E
authors: Wahle
authors: G Sebastiaan
authors: GS
authors: Winkler
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003593:Cytoplasm / Q000201:enzymology; D005095:Exoribonucleases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D055354:Exosomes / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D011061:Poly A / Q000235:genetics; D011487:Protein Conformation; D020871:RNA Stability / Q000235:genetics*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics*
chemical_list: D002352:Carrier Proteins; D005095:Exoribonucleases; D011061:Poly A; D012333:RNA, Messenger; C568693:PAN3 protein, human; C534418:cNOT6 protein, human; C551828:PAN2 protein, human