Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Bacterial RNA Polymerase00:43

Bacterial RNA Polymerase

Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Ribozymes02:47

Ribozymes

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...
Exon Recombination02:32

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Ribozymes02:47

Ribozymes

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...
Eukaryotic Evolution01:24

Eukaryotic Evolution

The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the nucleus-first hypothesis, the ancestral prokaryote first evolved a membrane to enclose DNA and form the nucleus. Conversely, the mitochondria-first hypothesis suggests that the nucleus was formed after endosymbiosis of mitochondria.
Contrary to the endosymbiont theory, the eukaryote-first hypothesis proposes that the simpler prokaryotic and...
Bacterial RNA Polymerase00:43

Bacterial RNA Polymerase

Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Flip-flop-induced relaxation of bending energy: implications for membrane remodeling.

Biophysical journal·2009
Same author

Reconstructing the emergence of cellular life through the synthesis of model protocells.

Cold Spring Harbor symposia on quantitative biology·2009
Same author

Semipermeable lipid bilayers exhibit diastereoselectivity favoring ribose.

Proceedings of the National Academy of Sciences of the United States of America·2005
Same author

One-step purification of recombinant proteins using a nanomolar-affinity streptavidin-binding peptide, the SBP-Tag.

Protein expression and purification·2001
Same author

Structural and kinetic characterization of an acyl transferase ribozyme.

Journal of the American Chemical Society·2001
Same author

Functional proteins from a random-sequence library.

Nature·2001
Same journal

Incoming US science academy chief vows to 'double down' on research.

Nature·2026
Same journal

Author Correction: Synthesis of enantioenriched atropisomers by biocatalytic deracemization.

Nature·2026
Same journal

Electrodeposited self-assembled molecules for perovskite photovoltaics.

Nature·2026
Same journal

Neutrino's nursery found: the 'Shadow Blaster'.

Nature·2026
Same journal

Dementia risk in middle-aged people linked to a blood protein.

Nature·2026
Same journal

Daily briefing: What's really happening with trust in science.

Nature·2026
See all related articles

Related Experiment Video

Updated: Jun 26, 2026

Directed Evolution Method in Saccharomyces cerevisiae: Mutant Library Creation and Screening
10:50

Directed Evolution Method in Saccharomyces cerevisiae: Mutant Library Creation and Screening

Published on: April 1, 2016

In vitro evolution suggests multiple origins for the hammerhead ribozyme.

K Salehi-Ashtiani1, J W Szostak

  • 1Howard Hughes Medical Institute and Department of Molecular Biology, Massachusetts General Hospital, Boston 02114, USA.

Nature
|November 2, 2001
PubMed
Summary
This summary is machine-generated.

The hammerhead ribozyme, a self-cleaving RNA motif, is the simplest and most common structure for RNA self-cleavage under physiological conditions. This suggests evolution favors the simplest solution for biochemical problems, explaining its widespread occurrence.

More Related Videos

In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity
09:16

In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity

Published on: March 25, 2020

Chemical Triphosphorylation of Oligonucleotides
13:19

Chemical Triphosphorylation of Oligonucleotides

Published on: June 2, 2022

Related Experiment Videos

Last Updated: Jun 26, 2026

Directed Evolution Method in Saccharomyces cerevisiae: Mutant Library Creation and Screening
10:50

Directed Evolution Method in Saccharomyces cerevisiae: Mutant Library Creation and Screening

Published on: April 1, 2016

In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity
09:16

In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity

Published on: March 25, 2020

Chemical Triphosphorylation of Oligonucleotides
13:19

Chemical Triphosphorylation of Oligonucleotides

Published on: June 2, 2022

Area of Science:

  • Molecular Biology
  • Evolutionary Biology
  • Biochemistry

Background:

  • The hammerhead ribozyme is a self-cleaving RNA motif found in diverse organisms, including plants, newts, schistosomes, and cave crickets.
  • Its sporadic distribution suggests either ancient origins or independent evolution across different species.
  • Understanding the evolutionary pressures shaping ribozyme distribution is crucial.

Purpose of the Study:

  • To investigate the evolutionary origins and distribution of the hammerhead ribozyme.
  • To determine the simplest RNA structure capable of self-cleavage at biologically relevant rates.
  • To explore whether evolutionary processes favor simpler solutions for biochemical functions.

Main Methods:

  • In vitro selection was employed to screen an unbiased library of random RNA sequences.
  • The selection aimed to identify self-cleaving motifs with activity comparable to known hammerhead ribozymes.
  • Experiments were conducted under near-physiological conditions to mimic biological environments.

Main Results:

  • The hammerhead ribozyme motif emerged as the most common and simplest RNA structure capable of self-cleavage.
  • This self-cleavage occurred at rates comparable to those observed in biological systems.
  • The findings were consistent across near-physiological conditions.

Conclusions:

  • The hammerhead ribozyme's prevalence suggests that evolutionary pathways are often channeled towards the simplest biochemical solutions.
  • This principle of selecting the simplest functional structure may explain its widespread occurrence in nature.
  • Laboratory selection mirrors natural evolutionary processes in favoring simplicity.