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Updated: Jan 6, 2026

Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
Structure-activity relationship of pseudoknot-type hammerhead ribozyme reveals key structural elements for enhanced
Mituhiro Yamada1,2, Yoshiyuki Tanaka1,3
1Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
Abstract:
The pseudoknot-type hammerhead ribozyme (PK-HHRz) is known to be activated by a pseudoknot interaction between loops I and II. To obtain maximal activation through the pseudoknot formation, we studied the structure-activity relationship of PK-HHRz. From these studies, the structural requirements of the PK-HHRz cleavage reaction were clearly defined. In addition, we discovered a PK-HHRz with higher cleavage activity than the wild-type sequence. Although modifications generally disrupt the activity of enzymes, in this case the elongation of loop II increased the activity of PK-HHRz. These new findings will form a structural basis for designing PK-HHRz variants for gene-therapeutic/manipulating agents and biochemical/nanotechnological tools.
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