Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Termination of Translation

Termination of Translation

The large ribosomal subunit has several important structures essential to translation. These include the peptidyl transferase center (PTC) - which is the site where the peptide bond is formed - and a large, internal, water-filled tube through which the nascent polypeptide moves. This latter structure is called the Peptide Exit Tunnel, and it begins at the PTC and spans the body of the large ribosomal subunit. During translation, as the nascent polypeptide chain is synthesized, it passes through...

Termination of Translation

Termination of Translation

From DNA to Protein

From DNA to Protein

The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of mRNAs, which in turn specify the sequence of amino acids making up all proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis...

Leaky Scanning

Leaky Scanning

During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...

The Central Dogma

The Central Dogma

The Central Dogma

The Central Dogma

The central dogma explains the flow of genetic information from DNA nucleotides to the amino acid sequence of proteins.
RNA is the Missing Link Between DNA and Proteins
In the early 1900s, scientists discovered that DNA stores all the information needed for cellular functions and that proteins perform most of these functions. However, the mechanisms of converting genetic information into functional proteins remained unknown for many years. Initially, it was believed that a single gene is...

You might also read

Related Articles

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

Sort by

Same author

Facultative mutualism between <i>Paramecium</i> and the intracellular <i>Rickettsiales</i> bacterium <i>Megaera</i> mediated by a horizontally acquired biotin operon.

ISME communications·2026

Same author

Subtle-seq reveals frequent ageing-associated chromosome fragmentation on nucleosome core DNA.

Nucleic acids research·2026

Same author

Two freshwater Hypotrichidium species (Ciliophora, Hypotrichia) from China, including H. flosaquae n. sp., with notes on undulating membrane patterns.

European journal of protistology·2026

Same author

A phylogenomic framework of Gastrotricha evolutionary relationships.

Molecular phylogenetics and evolution·2026

Same author

FlowCLOc, a New Tool for Selecting the Most Appropriate Antibodies in Flow Cytometry.

International journal of molecular sciences·2026

Same author

Genetic co-regulation of neopterin and Parkinson's disease.

NPJ Parkinson's disease·2026

Same journal

A viral ORFeome library for systems-level genetic dissection of host-pathogen interactions.

Cell·2026

Same journal

Co-option of lysosomal machinery shapes the evolution of the intracellular photosymbiosis supporting coral reefs.

Cell·2026

Same journal

LEF1 and niche factors determine T cell stemness across chronic diseases.

Cell·2026

Same journal

Recurrent patterns of TOP1-mediated neuronal genomic damage shared by major neurodegenerative disorders.

Cell·2026

Same journal

Four-dimensional molecular mapping from a spatial snapshot reveals the dynamics of hair follicle organogenesis.

Cell·2026

Same journal

Whole-cell particle-based digital twin simulations from 4D lattice light-sheet microscopy data.

Cell·2026

See all related articles

Search research articles

Related Experiment Video

Updated: Mar 17, 2026

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

Published on: August 1, 2016

Genetic Codes with No Dedicated Stop Codon: Context-Dependent Translation Termination.

Estienne Carl Swart¹, Valentina Serra², Giulio Petroni²

¹Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland.

|July 19, 2016

Summary

This summary is machine-generated.

The nuclear genetic code is not fixed. Some ciliates use stop codons as amino acids, challenging the standard genetic code and suggesting mRNA 3' ends help regulate translation termination.

More Related Videos

De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data

De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data

Published on: February 18, 2022

Xenopus laevis as a Model to Identify Translation Impairment

Xenopus laevis as a Model to Identify Translation Impairment

Published on: September 27, 2015

Related Experiment Videos

Last Updated: Mar 17, 2026

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

Published on: August 1, 2016

De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data

De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data

Published on: February 18, 2022

Xenopus laevis as a Model to Identify Translation Impairment

Xenopus laevis as a Model to Identify Translation Impairment

Published on: September 27, 2015

Area of Science:

Molecular Biology
Genetics
Evolutionary Biology

Background:

The nuclear genetic code is traditionally considered highly conserved and unambiguous.
Variations exist, particularly in ciliates, which can reassign stop codons to sense codons, leading to variant genetic codes.

Purpose of the Study:

To investigate the mechanisms of stop codon reassignment in ciliates.
To explore how translation machinery distinguishes stop codons from sense codons in variant genetic codes.
To understand the role of mRNA 3' ends in genetic code evolution.

Main Methods:

Ribosomal profiling was employed to analyze translation dynamics.
Analysis of stop codon usage and depletion patterns near coding sequence ends was performed.

Main Results:

Seven variant genetic codes were identified in ciliates, including three novel ones.
In two species, all 64 codons were efficiently translated as standard amino acids, with recognition of one or all stop codons.
Evidence suggests mRNA 3' ends contribute to context-dependent stop codon recognition.

Conclusions:

Stop codon reassignment is more prevalent than previously thought.
Context-dependent mechanisms, potentially involving mRNA 3' ends, play a crucial role in regulating translation termination and readthrough.
These mechanisms facilitate genetic code evolution and the emergence of novel genetic codes.