Minimum secondary structure requirements for catalytic activity of a self-splicing group I intron.
We have completed a comprehensive deletion analysis of the Tetrahymena ribozyme in order to define the minimum secondary structure requirements for phosphoester transfer activity of a self-splicing group I intron. A total of 299 nucleotides were removed in a piecewise fashion, leaving a catalytic core of 114 nucleotides that form 7 base-paired structural elements. Among the various deletion mutants are a 300-nucleotide single-deletion mutant and a 281-nucleotide double-deletion mutant whose activity exceeds that of the wild type when tested under physiologic conditions. Consideration of those structural elements that are essential for catalytic activity leads to a simplified secondary structure model of the catalytic core of a group I intron.
Department of Chemistry, Research Institute of Scripps Clinic, La Jolla, California 92037.
A A
AA
Beaudry
G F
GF
Joyce
D000818:Animals; D001483:Base Sequence; D007438:Introns; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009690:Nucleic Acid Conformation; D012322:RNA Precursors / Q000378:metabolism*; D012326:RNA Splicing; D016337:RNA, Catalytic / Q000235:genetics / Q000378:metabolism*; D013768:Tetrahymena / Q000235:genetics
D012322:RNA Precursors; D016337:RNA, Catalytic