Science, Vol 263, Issue 5143, 77-81
Copyright © 1994 by American Association for the Advancement of Science
Catalytic activity of an RNA domain derived from the U6-U4 RNA complex
JH Yang,
R Cedergren,
and
B Nadal-Ginard
Howard Hughes Medical Institute, Department of Cellular and Molecular Physiology, Harvard Medical School, Boston, MA.
U6 RNA contains two regions that are essential for proper splicing of nuclear precursor messenger RNA (pre-mRNA). A comparison of putative secondary structures of the U6-U4 RNA complexes from different phyla revealed a conserved domain that is similar to the catalytic hammerhead RNA motif. Although no catalytic activity was detected in the mammalian U6-U4 RNA complexes, two nucleotide changes in U6 RNA and one in U4 RNA conferred cleavage activity to the complex. Furthermore, the highly conserved domain of the wild-type complex, without the accompanying flanking regions, cleaved an RNA substrate and exhibited other characteristics of the hammerhead ribozyme. The possible involvement of this structure in pre-mRNA splicing is also discussed.
