Formation of mRNA 3' termini: stability and dissociation of a complex involving the AAUAAA sequence.
Formation of the 3' termini of mRNAs in animal cells involves endonucleolytic cleavage of a pre-mRNA, followed by polyadenylation of the newly formed end. Here we demonstrate that, during cleavage in vitro, the highly conserved AAUAAA sequence of the pre-mRNA forms a complex with a factor present in a crude nuclear extract. This complex is required for cleavage and polyadenylation. It normally is transient, but is very stable on cleaved RNA to which a single terminal cordycepin residue has been added. The complex can form either during the cleavage reaction, or on a synthetic RNA that ends at the polyadenylation site. Mutations which prevent cleavage also prevent complex formation. The complex dissociates during or after polyadenylation, enabling the released activities to catalyze a second round of cleavage.
D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003839:Deoxyadenosines / Q000494:pharmacology; D004722:Endoribonucleases; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D009154:Mutation; D009694:Nucleic Acid Precursors / Q000235:genetics; D009843:Oligoribonucleotides; D010957:Plasmids; D011061:Poly A / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012322:RNA Precursors; D012333:RNA, Messenger / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics; D016914:Ribonuclease H; D013539:Simian virus 40 / Q000235:genetics
D003839:Deoxyadenosines; D009694:Nucleic Acid Precursors; D009843:Oligoribonucleotides; D012322:RNA Precursors; D012333:RNA, Messenger; D012367:RNA, Viral; D011061:Poly A; D012313:RNA; D004722:Endoribonucleases; D016914:Ribonuclease H