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

Mutations

Mutations

Mutations

Mutations

Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations can be characterized in a number of different ways: whether and how they alter the amino acid sequence of the protein, whether they occur over a small or large area of DNA, and whether they occur in somatic cells or germline cells.
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...

Viral Mutations

Viral Mutations

A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...

Mutation, Gene Flow, and Genetic Drift

Mutation, Gene Flow, and Genetic Drift

In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions of Hardy-Weinberg equilibrium can alter the genetic variation of a given population. Conditions that change the genetic variability of a population include mutations, natural selection, non-random mating, gene flow, and genetic drift (small population size).

Point and Frameshift Mutations

Point and Frameshift Mutations

Point mutations are genetic alterations involving the change of a single nucleotide base pair in DNA. Depending on how the alteration affects protein synthesis, they can lead to various consequences.Point mutations fall into the following types:Silent mutations occur when a nucleotide change does not alter the amino acid sequence due to the redundancy of the genetic code. For instance, changing ACC to ACA still encodes threonine, leaving the protein function unaffected. This occurs because...

Mutations in Microorganisms

Mutations in Microorganisms

Mutations are heritable changes in an organism’s genome involving alterations in the base sequence of DNA or RNA. These changes can influence cellular processes and phenotypic traits, potentially transforming the unaltered wild type into a mutant form. Such changes, termed forward mutations, are pivotal in shaping the genetic diversity of organisms.RNA viruses exhibit the highest mutation rates due to the absence of robust proofreading mechanisms during genome replication. In contrast,...

You might also read

Related Articles

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

Sort by

Same author

The Evolution and Impact of Pharmacist-Driven Antimicrobial Stewardship Programs: A Review.

Current reviews in clinical and experimental pharmacology·2026

Same author

Hydrostatic pressure spectroscopy reveals the adaptation of microbial rhodopsins to high-pressure environment.

Scientific reports·2026

Same author

BNIP3/NIX-dependent mitophagy: molecular mechanisms and physiological roles.

Journal of biochemistry·2026

Same author

Structural insights into spectral tuning and retinal exchange in cone visual pigments.

Science (New York, N.Y.)·2026

Same author

The Health of Nations Fund: Financing global drug development.

PLOS global public health·2026

Same author

Comparative toxicity of nickel titanate and calcium manganite perovskite nanomaterials in human and bacterial systems: Implications for environmental and health risks.

Chemosphere·2026

Search research articles

Related Experiment Video

Updated: Feb 7, 2026

The Lambda Select cII Mutation Detection System

The Lambda Select cII Mutation Detection System

Published on: April 26, 2018

Mutation Study of Heliorhodopsin 48C12.

Manish Singh¹, Keiichi Inoue^1,2,3,4, Alina Pushkarev⁵

¹Department of Life Science and Applied Chemistry , Nagoya Institute of Technology , Showa-ku, Nagoya 466-8555 , Japan.

|July 24, 2018

Summary

Newly discovered heliorhodopsins (HeRs) are a diverse protein family. Alanine scanning identified key residues for pigment formation and engineered HeRs with novel absorption spectra.

More Related Videos

Quantification of Colonic Stem Cell Mutations

Quantification of Colonic Stem Cell Mutations

Published on: September 25, 2015

Measuring Microbial Mutation Rates with the Fluctuation Assay

Measuring Microbial Mutation Rates with the Fluctuation Assay

Published on: November 28, 2019

Related Experiment Videos

Last Updated: Feb 7, 2026

The Lambda Select cII Mutation Detection System

The Lambda Select cII Mutation Detection System

Published on: April 26, 2018

Quantification of Colonic Stem Cell Mutations

Quantification of Colonic Stem Cell Mutations

Published on: September 25, 2015

Measuring Microbial Mutation Rates with the Fluctuation Assay

Measuring Microbial Mutation Rates with the Fluctuation Assay

Published on: November 28, 2019

Area of Science:

Biochemistry
Molecular Biology
Structural Biology

Background:

Rhodopsins are essential photoactive proteins with two known families: microbial and animal.
Heliorhodopsins (HeRs) represent a newly identified, globally distributed rhodopsin family with low sequence identity to known types.
The molecular properties and chromophore interactions of HeRs remain largely uncharacterized.

Purpose of the Study:

To investigate the molecular determinants of chromophore interaction in heliorhodopsins.
To identify specific amino acid residues critical for pigment formation in HeRs.
To engineer heliorhodopsins with altered spectral properties.

Main Methods:

Alanine scanning mutagenesis was applied to 30 candidate residues in the heliorhodpsin 48C12 variant.
Spectroscopic analysis was performed on wild-type and mutant heliorhodopsins to assess pigment formation and absorption spectra.
Site-directed mutagenesis was used to combine mutations and engineer pigments with specific absorption wavelengths.

Main Results:

Mutagenesis revealed that 12 residues did not affect absorption, 8 caused blue-shifts, 6 caused red-shifts, and 4 abolished pigment formation.
Residues R104, Y108, G145, and K241 were identified as crucial for heliorhodopsin pigment formation.
Engineered double mutants (S112A/M141A and H80A/S237A) produced pigments absorbing at 523 nm and 571 nm, respectively.

Conclusions:

This study elucidates the roles of specific residues in heliorhodopsin structure and function.
Key residues responsible for chromophore binding and spectral tuning in HeRs were identified.
The engineering of novel heliorhodopsin pigments expands our understanding of their photophysical diversity.