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 UI snRNP initiates splicing 22.7 The E complex can be formed in alternative ways 22. 8 5 snRNPs form the spliceosome 22.9 An alternative splicing apparatus uses different snRNP 22 10 Group II introns autosplice via lariat formation 22. 11 Alternative splicing involves differential use of splice junctions 22 12 CiS-splicing and trans-splicing reactions 22 13 Yeast tRNA splicing involves cutting and rejoining 22 14 The unfolded protein response is related to tRNA splicing 22. 15 The 3c ends of poll and pollll transcripts are generated by termination 22.16 The 3c ends of mRNAS are generated by cleavage 22 17 Cleavage of the 3c end may require a small rNA 22.18 Production of rRNA requires cleavage and modification events 22 19 Small RNAs are required for rRNA processing 消当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 22.9 An alternative splicing apparatus uses different snRNPs 22.10 Group II introns autosplice via lariat formation 22.11 Alternative splicing involves differential use of splice junctions 22.12 cis-splicing and trans-splicing reactions 22.13 Yeast tRNA splicing involves cutting and rejoining 22.14 The unfolded protein response is related to tRNA splicing 22.15 The 3¢ ends of polI and polIII transcripts are generated by termination 22.16 The 3¢ ends of mRNAs are generated by cleavage 22.17 Cleavage of the 3¢ end may require a small RNA 22.18 Production of rRNA requires cleavage and modification events 22.19 Small RNAs are required for rRNA processing