Related Experiment Video

Updated: May 22, 2026

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development
09:32

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Published on: June 15, 2017

Regulation of transcription through light-activation and light-deactivation of triplex-forming oligonucleotides in

Jeane M Govan1, Rajendra Uprety, James Hemphill

  • 1Department of Chemistry, North Carolina State University, Raleigh, 27695, United States.

ACS Chemical Biology
|May 1, 2012
PubMed

Insights

Light-activated triplex-forming oligonucleotides (TFOs) offer temporal control over gene expression. This study demonstrates novel methods for both photochemical activation and deactivation of TFOs using UV light.

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Photochemistry

Background:

  • Triplex-forming oligonucleotides (TFOs) are key regulators of gene expression via transcription inhibition.
  • Temporal control of gene regulation is crucial for understanding cellular processes and developing therapeutic strategies.

Purpose of the Study:

  • To develop light-activated TFOs for precise temporal regulation of gene transcription.
  • To demonstrate both photochemical activation and deactivation of gene expression using TFOs.

Main Methods:

  • Site-specific incorporation of caged thymidine and deoxycytidine nucleotides into TFOs.
  • UV irradiation to trigger the removal of caging groups and modulate TFO activity.
  • Assessment of TFO efficacy in regulating transcription and gene expression.

Main Results:

  • Light-activated TFOs were successfully synthesized, enabling temporal control over transcription.
  • UV irradiation photochemically activated TFOs by removing caging groups, inhibiting transcription.
  • Photochemical deactivation of TFOs was achieved, leading to gene expression activation.
  • Hairpin loop structures enhanced the efficacy of phosphodiester DNA-based TFOs in cell culture.

Conclusions:

  • This work presents the first light-regulated TFOs for photochemical control of gene expression.
  • Nucleobase-caging technology provides a powerful tool for temporal regulation of transcription.
  • Optimized TFO designs, including hairpin loops, improve efficacy in biological systems.

More Related Videos

Chromatin Immunoprecipitation Assay Using Micrococcal Nucleases in Mammalian Cells11:42

Chromatin Immunoprecipitation Assay Using Micrococcal Nucleases in Mammalian Cells

Published on: May 10, 2019

Bioluminescent Optogenetics 2.0: Harnessing Bioluminescence to Activate Photosensory Proteins In Vitro and In Vivo07:19

Bioluminescent Optogenetics 2.0: Harnessing Bioluminescence to Activate Photosensory Proteins In Vitro and In Vivo

Published on: August 4, 2021

Related Concept Videos

Regulation of Expression at Multiple Steps01:23

Regulation of Expression at Multiple Steps

The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...
Regulation of Expression Occurs at Multiple Steps02:24

Regulation of Expression Occurs at Multiple Steps

Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Combinatorial Gene Control02:33

Combinatorial Gene Control

Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
Co-activators and Co-repressors02:04

Co-activators and Co-repressors

Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
RNA Polymerase II Accessory Proteins02:36

RNA Polymerase II Accessory Proteins

Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
Eukaryotic Transcription Inhibitors01:52

Eukaryotic Transcription Inhibitors

Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...