Download MendeleyMetal binding and base ionization in the U6 RNA intramolecular stem-loop structure.
Huppler, A., Nikstad, L.J., Allmann, A.M., Brow, D.A., Butcher, S.E.(2002) Nat Struct Biol 9: 431-435
- PubMed: 11992125
- DOI: https://doi.org/10.1038/nsb800
- Primary Citation of Related Structures:
1LC6 - PubMed Abstract:
U6 RNA is a key component of the catalytic core of the spliceosome. A metal ion essential for the first catalytic step of pre-mRNA splicing binds to the U80 Sp phosphate oxygen within the yeast U6 intramolecular stem-loop (ISL). Here we present the first structural data for U6 RNA, revealing the three-dimensional structure of the highly conserved U6 ISL. The ISL binds metal ion at the U80 site with the same stereo specificity as the intact spliceosome. The metal-binding site is adjacent to a readily protonated C.A wobble pair. Protonation of the C.A pair and metal binding are mutually antagonistic. These results support a ribozyme model for U6 RNA function and suggest a possible mechanism for the regulation of RNA splicing.
Organizational Affiliation:
Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, Wisconsin 53706, USA.
