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

What are Viruses?00:50

What are Viruses?

Overview
Translation01:31

Translation

Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Leaky Scanning02:28

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 stands for...
Translation01:31

Translation

Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Proteins are called the...
Viruses with RNA Genomes01:29

Viruses with RNA Genomes

RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
Subviral Agents01:29

Subviral Agents

Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...

You might also read

Related Articles

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

Sort by
Same author

Exploring life's hidden majority: microbial dark matter symposium highlights.

mSphere·2026
Same author

Revised 16S rRNA V4 hypervariable region targeting primers enhance detection of Patescibacteria and other lineages across diverse environments.

ISME communications·2026
Same author

Vicennial metagenomic time series unveils evolutionary dynamics of giant viruses in a freshwater ecosystem.

Nature communications·2026
Same author

Draft genome sequence of <i>Aquicella lusitana</i> DSM 16500<sup>T</sup> isolated from a spa.

Microbiology resource announcements·2026
Same author

Genome sequences of seven <i>Streptomyces</i> isolates for genome prospecting.

Microbiology resource announcements·2026
Same author

Single nucleotide variants drive evolutionary phage-host arms race in anaerobic carbon dioxide-converting microbiome.

Nature communications·2026

Related Experiment Video

Updated: Jun 4, 2026

Measurement of Specific Mycobacterial Mistranslation Rates with Gain-of-function Reporter Systems
06:18

Measurement of Specific Mycobacterial Mistranslation Rates with Gain-of-function Reporter Systems

Published on: April 26, 2019

Giant viruses with an expanded complement of translation system components.

Frederik Schulz1, Natalya Yutin2, Natalia N Ivanova3

  • 1Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA. fschulz@lbl.gov koonin@ncbi.nlm.nih.gov twoyke@lbl.gov.

Science (New York, N.Y.)
|April 8, 2017
PubMed
Summary

Giant viruses, like newly discovered Klosneuviruses, blur the lines between viruses and cellular life. Phylogenomic analysis reveals these giant viruses evolved from smaller viruses, not a cellular ancestor, through gene acquisition.

More Related Videos

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance
09:59

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance

Published on: July 21, 2023

DNA Virus Detection System Based on RPA-CRISPR/Cas12a-SPM and Deep Learning
04:17

DNA Virus Detection System Based on RPA-CRISPR/Cas12a-SPM and Deep Learning

Published on: May 10, 2024

Related Experiment Videos

Last Updated: Jun 4, 2026

Measurement of Specific Mycobacterial Mistranslation Rates with Gain-of-function Reporter Systems
06:18

Measurement of Specific Mycobacterial Mistranslation Rates with Gain-of-function Reporter Systems

Published on: April 26, 2019

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance
09:59

Application of the Intelligent High-Throughput Antimicrobial Sensitivity Testing/Phage Screening System and Lar Index of Antimicrobial Resistance

Published on: July 21, 2023

DNA Virus Detection System Based on RPA-CRISPR/Cas12a-SPM and Deep Learning
04:17

DNA Virus Detection System Based on RPA-CRISPR/Cas12a-SPM and Deep Learning

Published on: May 10, 2024

Area of Science:

  • Virology
  • Genomics
  • Evolutionary Biology

Background:

  • Giant viruses challenge the traditional definition of viruses, possessing complex genomes with cellular signatures.
  • Some giant viruses encode translation system components, leading to hypotheses of a fourth domain of cellular life.

Purpose of the Study:

  • To report the discovery of a novel group of giant viruses, Klosneuviruses.
  • To investigate the evolutionary origins of Klosneuviruses and their complex genomes.

Main Methods:

  • Metagenomic data analysis to identify novel viral sequences.
  • Phylogenomic analysis of viral genes, particularly translation system components.
  • Comparative genomics to assess gene content and evolutionary relationships.

Main Results:

  • Discovery of Klosneuviruses, a novel group of giant viruses.
  • Klosneuviruses possess an expanded translation machinery, including aminoacyl-tRNA synthetases for all 20 amino acids.
  • Phylogenomic analysis indicates Klosneuviruses are not derived from a cellular ancestor but evolved from smaller viruses via extensive host gene gain.

Conclusions:

  • Klosneuviruses represent a significant expansion of known giant viruses.
  • The evolutionary trajectory of Klosneuviruses supports a viral origin through gene acquisition rather than a descent from a cellular ancestor.
  • Giant viruses continue to challenge our understanding of the virus-cell dichotomy and viral evolution.