@article{,
title = {An mRNA is capped by a 2', 5' lariat catalyzed by a group I-like ribozyme},
author = {H Nielsen and E Westhof and S Johansen},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16141078},
isbn = {16141078},
year = {2005},
date = {2005-01-01},
journal = {Science},
volume = {309},
number = {5740},
pages = {1584-1587},
abstract = {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 reaction similar to the first step of splicing in group II introns and spliceosomal introns. The resulting short lariat, by forming a protective 5' cap, might have been useful in a primitive RNA world.},
note = {1095-9203 (Electronic)
Journal Article},
keywords = {ase Sequence Catalysis Endonucleases/biosynthesis/*genetics Esterification *Introns Molecular Sequence Data RNA Caps/*chemistry *RNA Splicing RNA, Catalytic/chemistry/*metabolism Research Support, Non-U.S. Gov't, Unité ARN, WESTHOF},
pubstate = {published},
tppubtype = {article}
}
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 reaction similar to the first step of splicing in group II introns and spliceosomal introns. The resulting short lariat, by forming a protective 5' cap, might have been useful in a primitive RNA world.