TY - JOUR
T1 - Reverse self-splicing of the tetrahymena group I intron
T2 - Implication for the directionality of splicing and for intron transposition
AU - Woodson, Sarah A.
AU - Cech, Thomas R.
N1 - Funding Information:
We wish to thank Arthur Zaug for technical advice and helpful discussions, and for preparation of Tr RNA polymerase. We also thank Cheryl Grosshans for synthesis of DNA oligonucleptides. S. W. was supported by an American Cancer Society postdoctoral fellowship, and this work was supported in part by a grant from the National Institutes of Health.
PY - 1989/4/21
Y1 - 1989/4/21
N2 - Using short oligoribonucleotides as ligated exon substrates, we show that splicing of the Tetrahymena rRNA group I intron is fully reversible in vitro. Incubation of ligated exon RNA with linear intron produces a molecule in which the splice site sequences of the precursor are reformed. Reversal of self-splicing is favored by high RNA concentration, high magnesium and temperature, and the absence of guanosine. 5′ exon sequences that can pair with the internal guide sequence of the intron are required, whereas 3′ exon sequences are not essential. Integration of the intron into ligated exon substrates that have the ability to form stem-loop structures is reduced at least one order of magnitude over short, unstructured substrates. We propose that the formation of these structures helps drive splicing in the forward direction. We also show that the Tetrahymena intron can integrate into a β-globin transcript. This has implications for transposition of group I introns.
AB - Using short oligoribonucleotides as ligated exon substrates, we show that splicing of the Tetrahymena rRNA group I intron is fully reversible in vitro. Incubation of ligated exon RNA with linear intron produces a molecule in which the splice site sequences of the precursor are reformed. Reversal of self-splicing is favored by high RNA concentration, high magnesium and temperature, and the absence of guanosine. 5′ exon sequences that can pair with the internal guide sequence of the intron are required, whereas 3′ exon sequences are not essential. Integration of the intron into ligated exon substrates that have the ability to form stem-loop structures is reduced at least one order of magnitude over short, unstructured substrates. We propose that the formation of these structures helps drive splicing in the forward direction. We also show that the Tetrahymena intron can integrate into a β-globin transcript. This has implications for transposition of group I introns.
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U2 - 10.1016/0092-8674(89)90971-9
DO - 10.1016/0092-8674(89)90971-9
M3 - Article
C2 - 2702692
AN - SCOPUS:0024975570
VL - 57
SP - 335
EP - 345
JO - Cell
JF - Cell
SN - 0092-8674
IS - 2
ER -