Related Experiment Video
Updated: Jul 15, 2026
09:19
RNA Catalyst as a Reporter for Screening Drugs against RNA Editing in Trypanosomes
Published on: July 22, 2014
Promiscuous catalysis by the tetrahymena group I ribozyme
Marcello Forconi1, Daniel Herschlag
1Department of Biochemistry, B400 Beckman Center, Stanford University, Stanford, California 94305-5307, USA.
Journal of the American Chemical Society
|April 28, 2005
Summary
Enzymes can perform multiple reactions, a trait called catalytic promiscuity. This study shows a ribozyme can catalyze a new reaction with a neutral substrate, revealing insights into RNA evolution.
Area of Science:
- Biochemistry
- Molecular Biology
- Origins of Life
Background:
- Catalytic promiscuity, the ability of enzymes to catalyze multiple reactions, is crucial for evolving new functions in proteins.
- Promiscuous activities may have been vital in the early RNA world for developing catalytic diversity.
Purpose of the Study:
- To investigate the catalytic promiscuity of the Tetrahymena Group I ribozyme.
- To explore the role of substrate charge and geometry in ribozyme catalysis and evolution.
Main Methods:
- Characterization of the Tetrahymena Group I ribozyme's activity with a neutral phosphonate diester substrate.
- Comparison of catalytic efficiency with the natural anionic substrate and a previously observed aminoacyl transfer reaction.
Main Results:
- The ribozyme exhibits a new promiscuous activity, catalyzing the guanosine attack on a neutral phosphonate diester.
- This reaction is accelerated by approximately 1 x 10^6-fold, significantly higher than aminoacyl transfer but lower than the natural reaction.
- Results indicate both charge and geometry are critical for the ribozyme's natural catalytic function.
Conclusions:
- Catalytic promiscuity in ribozymes can be modulated by substrate properties like charge and geometry.
- Promiscuous activities may have been enhanced through RNA domain rearrangement, contributing to the evolution of catalytic functions.
Related Concept Videos
02:53Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
01:56Riboswitches
Riboswitches are non-coding mRNA domains that regulate the transcription and translation of downstream genes without the help of proteins. Riboswitches bind directly to a metabolite and can form unique stem-loop or hairpin structures in response to the amount of the metabolite present. They have two distinct regions – a metabolite-binding aptamer and an expression platform.
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
02:47Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
02:47Ribozymes
The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
Ribozymes can be...
Ribozymes can be...
02:53Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
01:23Transcriptional Regulation: Riboswitches
Riboswitches are RNA elements that regulate gene expression by altering their secondary structures in response to specific effector molecules. These elements, located in the leader regions of certain mRNAs, act as transcriptional regulators by toggling between alternative conformations to control downstream gene expression. Riboswitch-mediated regulation is a precise mechanism for modulating biosynthetic pathways, as exemplified by the riboflavin biosynthesis pathway in Bacillus...