22.2 Nuclear splice junctions are interchangeable but are read in pairs GT-AG rule describes the presence of these constant dinucleotides at the first two and last two positions of introns of nuclear genes. Splice sites are the sequences immediately surrounding the exon-intron boundaries. 情菜大兰
GT-AG rule describes the presence of these constant dinucleotides at the first two and last two positions of introns of nuclear genes. Splice sites are the sequences immediately surrounding the exon-intron boundaries. 22.2 Nuclear splice junctions are interchangeable but are read in pairs
22.2 Nuclear splice junctions are interchangeable but are read in pairs Left (5)site Right(3)site Ex64G73G10062463 12Py N C6A1010N Exon Intron Figure 22.3 The ends of nuclear introns are defined by the GT-AG rule 清苇大当
Figure 22.3 The ends of nuclear introns are defined by the GT-AG rule 22.2 Nuclear splice junctions are interchangeable but are read in pairs
22.2 Nuclear splice junctions are interchangeable but are read in pairs Comrect splicing removes 3 introns by pairwise recognition ofthe junctions GU GU GU Figure 22.4 Splicing junctions are P airing of wrong junctions would remove exons as well as introns,but aberant products are not found recognized GU GU only in the correct pairwise GU GU rGU combinations. 清菜大当
Figure 22.4 Splicing junctions are recognized only in the correct pairwise combinations. 22.2 Nuclear splice junctions are interchangeable but are read in pairs
22.2 Nuclear splice junctions are interchangeable but are Thevector contains two exons that are spliced together in the transcript promoter5'splice junction 3splice junction Figure 2.20 A special exon int ron exon splicing vector is used for exon trapping.If an A genomic fragment is inserted into the intron;any exon in the exon is present in the fragment will be found in the RNA Genomic fragment genomic fragment,its intron exon intron sequence will be Insert into recovered in the cloning site cytoplasmic RNA,but if the genomic fragment consists exon intron exon intron exon solely of an intron, Transcription splicing 清第大当
Figure 2.20 A special splicing vector is used for exon trapping. If an exon is present in the genomic fragment, its sequence will be recovered in the cytoplasmic RNA, but if the genomic fragment consists solely of an intron, 22.2 Nuclear splice junctions are interchangeable but are read in pairs
Gene 5.6 kb 22.2 Nuclear splice junctions 11121314■516171 are interchangeable but are read in pairs mRNA=1.1 kb Figure 22.5 Northern Primary transcript(5.5 kb) blotting of nuclear RNA with an ovomucoid probe identifies discrete Lacks introns 5 6 precursors to mRNA.The Lacks introns 4,5,6,&7 contents of the more prominent bands are Contains only intron 3 indicated.Photograph kindly provided by Bert O'Malley. mRNA (1.1 kb) 清菜大当
Figure 22.5 Northern blotting of nuclear RNA with an ovomucoid probe identifies discrete precursors to mRNA. The contents of the more prominent bands are indicated. Photograph kindly provided by Bert O'Malley. 22.2 Nuclear splice junctions are interchangeable but are read in pairs