Related Experiment Video
Updated: Jun 17, 2026
09:08
Rapid Optimization of a Light-Inducible System to Control Mammalian Gene Expression
Published on: November 4, 2025
Light-induced gene expression using messenger RNA molecules.
Sigurd Bøe1, Stein Saebøe-Larssen, Eivind Hovig
1Department of Tumor Biology, The Norwegian Radium Hospital, Rikshospitalet HF, Oslo 0310, Norway.
Oligonucleotides
|December 30, 2009
Summary
Researchers developed a new method for delivering messenger RNA (mRNA) using photochemical internalization (PCI) technology. This strategy enhances mRNA delivery and protein production in a controlled, site-specific manner without harming cells.
Area of Science:
- Biotechnology
- Molecular Biology
- Drug Delivery Systems
Background:
- Messenger RNA (mRNA) therapeutics face challenges due to endocytic pathway entrapment and lack of targeted delivery.
- Polyplexes, commonly used for mRNA delivery, struggle to escape the endosome, limiting therapeutic potential.
- Specific targeting remains a significant hurdle for effective mRNA-based gene regulation.
Purpose of the Study:
- To develop a site-specific delivery strategy for mRNA molecules using photochemical internalization (PCI) technology.
- To overcome the limitations of endocytic pathway entrapment for enhanced mRNA delivery.
- To enable controllable, site-specific protein production from delivered mRNA.
Main Methods:
- Utilized photochemical internalization (PCI) technology for mRNA delivery.
- Employed EGFP mRNA as a model system to evaluate delivery efficiency.
- Investigated the impact of the nitrogen/phosphate (N/P) ratio on delivery efficacy.
- Assessed cell viability post-delivery to ensure safety.
Main Results:
- Achieved a 10- to 40-fold increase in EGFP-positive cells with PCI treatment compared to untreated samples.
- Demonstrated that mRNA delivery efficiency was highly dependent on the N/P ratio.
- Confirmed potent delivery of mRNA via polyplexes and PCI through the endocytic pathway.
- Showed no loss of cell viability in PCI-treated samples, indicating a safe delivery method.
Conclusions:
- The developed strategy enables potent mRNA delivery and protein production via the endocytic pathway using polyplexes and PCI.
- Photochemical internalization (PCI) significantly enhances the number of mRNA-expressing cells.
- This approach offers controllable, time- and site-specific protein production, overcoming key limitations in mRNA therapeutics.
Related Concept Videos
02:11Reporter Genes
Reporter genes are a type of protein-coding gene that are often tagged to a gene of interest. Once inside a target cell, reporter genes usually produce visually identifiable characteristics like fluorescence and luminescence when expressed along with the gene of interest. Thus, reporter genes “report” the presence or absence of genes of interest in an organism, determine the gene expression pattern, or track the physical location of a DNA segment or protein in the cell.
Commonly used reporter...
Commonly used reporter...
02:15Experimental RNAi
RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
01:36What is Gene Expression?
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is comprised of nucleotides and proteins are comprised of amino acids, a mediator is required to convert the information encoded in DNA into proteins. This mediator is the messenger RNA (mRNA). mRNA copies the blueprint from DNA by a process called transcription. In eukaryotes, transcription occurs in the nucleus by complementary base-pairing with the DNA template. The mRNA is then processed and...
01:42What is Gene Expression?
Overview
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
Gene expression is the process in which DNA directs the synthesis of functional products, that is, proteins. Cells can regulate gene expression at various stages. It allows organisms to generate different cell types and enables cells to adapt to internal and external factors.
Genetic Information Flows from DNA to RNA to Protein
A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is made up of nucleotides and proteins consist of amino...
01:23RNA Interference
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:23Regulation 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...