20.1 Introduction 20.2 Eukaryotic RNA polymerases consist of many subunits 20.3 Promoter elements are defined by mutations and footprinting 20.4 RNA polymerase I has a bipartite promoter 20.5 RNA polymerase III uses both downstream and upstream promoters 20.6 The startpoint for RNA polymerase II 20.7 TBP is a universal factor 20.8 TBP binds DNA in an unusual way
22.1 Introduction 22.2 Nuclear splice junctions are short sequences 22.3 Splice junctions are read in pairs 22.4 Nuclear splicing proceeds through a lariat 22.5 snRNAs are required for splicing 22.6 U1 snRNP initiates splicing 22.7 The E complex can be formed in alternative ways 22.8 5 snRNPs form the spliceosome
23.1 Introduction 23.2 Group I introns undertake self-splicing by transesterification 23.3 Group I introns form a characteristic secondary structure 23.4 Ribozymes have various catalytic activities 23.5 Some introns code for proteins that sponsor mobility 23.6 The catalytic activity of RNAase P is due to RNA 23.7 Viroids have catalytic activity 23.8 RNA editing occurs at individual bases