The Journal of Biochemistry
Online ISSN : 1756-2651
Print ISSN : 0021-924X
Identification of the Nucleotides in the A-Rich Bulge of the Tetrahymena Ribozyme Responsible for an Efficient Self-Splicing Reaction
Yoshiya IkawaAyako OkadaHiroshi ImahoriHideaki ShiraishiTan Inoue
Author information

1997 Volume 122 Issue 4 Pages 878-882


P5abc is a large extension of the P5 element characteristic of subclasses IC1 and IC2 of group I introns. It has a conserved region termed the A-rich bulge, that is responsible for activation of the Tetrahymena self-splicing intron. By employing a modified color-colony assay system, we identified four adenosines in the bulge that are responsible for an efficient splicing reaction. On comparison with the X-ray crystal structure of the P4-5-6 domains of the Tetrahymena intron, three adenosines at positions 183, 184, and 186 were found to be identical to those significantly contributing to the formation of its tertiary structure. However, our results show that an adenosine at 187 is involved in the formation of a Watson-Crick base pair with U135, although it forms a Hoogsteen base pair in the crystal structure.

Information related to the author
© The Japanese Biochemical Society
Previous article Next article