An mRNA Is Capped by a 2', 5' Lariat Catalyzed by a Group I-Like Ribozyme

@article{Nielsen2005AnMI,
  title={An mRNA Is Capped by a 2', 5' Lariat Catalyzed by a Group I-Like Ribozyme},
  author={Henrik Nielsen and Eric Westhof and Steinar Daae Johansen},
  journal={Science},
  year={2005},
  volume={309},
  pages={1584 - 1587}
}
Twin-ribozyme introns are formed by two ribozymes belonging to the group I family and occur in some ribosomal RNA transcripts. The group I-like ribozyme, GIR1, liberates the 5′ end of a homing endonuclease messenger RNA in the slime mold Didymium iridis. We demonstrate that this cleavage occurs by a transesterification reaction with the joining of the first and the third nucleotide of the messenger by a 2′,5′-phosphodiester linkage. Thus, a group I-like ribozyme catalyzes an RNA branching… Expand
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