Origin of the phosphate at the ligation junction produced by self-splicing of Tetrahymena thermophila pre-ribosomal RNA.
The exons of the self-splicing pre-ribosomal RNA of Tetrahymena thermophila are joined accurately in vitro, even when only 33 nucleotides of the natural 5' exon and 38 nucleotides of the natural 3' exon remain. RNA fingerprint analysis was used to identify the unique ribonuclease T1 oligonucleotide generated by exon ligation. Secondary digests of the ligation junction oligonucleotide with ribonuclease A confirmed the identity of the fragment and demonstrated that the phosphate group that forms the phosphodiester bond at the ligation junction is derived from the 5' position of a uridine nucleotide in the RNA. This observation supports the prediction that the splice junction phosphate is derived from the 3' splice site. These results emphasize the mechanistic similarities of RNA splicing reactions of the group I introns, group II introns and nuclear pre-mRNA introns.
Price
J V
JV
Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder 80309.
D000818:Animals; D005091:Exons; D010710:Phosphates; D012322:RNA Precursors; D012326:RNA Splicing; D012335:RNA, Ribosomal; D013768:Tetrahymena / Q000235:genetics*
D010710:Phosphates; D012322:RNA Precursors; D012335:RNA, Ribosomal