22.3 Nuclear splicing proceeds through a lariat Lariat is an intermediate in RNA splicing in which a circular structure with a tail is created by a 5'-2'bond. 清苇大当
Lariat is an intermediate in RNA splicing in which a circular structure with a tail is created by a 5′-2′ bond. 22.3 Nuclear splicing proceeds through a lariat
5'site 3'site 22.3 Nuclear splicing 51 GU UACUAACAG 3 proceeds through a lariat PV NY Cut at 5'site &form lariat by 5'2'bond connecting the intron 5'-G to the 2'of A at the branch site Figure 22.6 3 Splicing occurs in UACUAACAG two stages,in Cut at 3'site join exons;intron released as lariat which the5￠ 5 3 UACUAAC A5 3 exon is separated and then is joined Debranch intron to the3￠exon. 5GU 情菜大兰 UACUAAC AC
Figure 22.6 Splicing occurs in two stages, in which the 5￠ exon is separated and then is joined to the 3￠ exon. 22.3 Nuclear splicing proceeds through a lariat
22.3 Nuclear splicing proceeds through a lariat ExonO-P O-P-Exon 2 Figure 22.7 Nuclear splicing occurs by two Exon-DH transesterification reactions in which O-P-Exon 2 a free OH end attacks a phosphodiester Exon P-Exon 2 bond 清第大当 -OH
Figure 22.7 Nuclear splicing occurs by two transesterification reactions in which a free OH end attacks a phosphodiester bond. 22.3 Nuclear splicing proceeds through a lariat
22.4 The spliceosome contains snRNAs scRNA is any one of several small cytoplasmic RNA molecules present in the cytoplasm and (sometimes)nucleus. snRNA(small nuclear RNA)is any one of many small RNA species confined to the nucleus;several of the snRNAs are involved in splicing or other RNA processing reactions. 情菜大兰
scRNA is any one of several small cytoplasmic RNA molecules present in the cytoplasm and (sometimes) nucleus. snRNA (small nuclear RNA) is any one of many small RNA species confined to the nucleus; several of the snRNAs are involved in splicing or other RNA processing reactions. 22.4 The spliceosome contains snRNAs
Domain D 22.4 The spliceosome UC contains snRNAs VoCE Sm binding Domain C Figure 22.8 U1 snRNA has a base CG paired structure Domain B UA that creates several domains.The5￠ CCUAU CGGA CGGGAC GACGGUCCA U UCA UApppGe exon GUAA GUA intion3' end remains single stranded and can Intron pairing base pair with the 5￠splicing site. GCACU 清菜大兰 Domain A
Figure 22.8 U1 snRNA has a base paired structure that creates several domains. The 5￠ end remains single stranded and can base pair with the 5￠ splicing site. 22.4 The spliceosome contains snRNAs