Related Experiment Video
Updated: Jun 4, 2026
10:28
Repressing Gene Transcription by Redirecting Cellular Machinery with Chemical Epigenetic Modifiers
Published on: September 20, 2018
Spatial control of gene expression within a scaffold by localized inducer release
Priya R Baraniak1, Devin M Nelson, Cory E Leeson
1Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, USA.
Biomaterials
|January 29, 2011
Summary
Controlled gene expression on biomaterials was achieved using a novel poly(ester urethane) urea (PEUU) system. This method precisely controls gene activation via inducer release, offering potential for tissue regeneration applications.
Area of Science:
- Biomaterials Science
- Molecular Biology
- Tissue Engineering
Background:
- Gene expression control is crucial for cellular function and tissue engineering.
- Current methods often rely on DNA delivery, which can be unstable.
- Controlled release of signaling molecules from biomaterials offers an alternative approach.
Purpose of the Study:
- To investigate the controlled release of an inducer ligand from a poly(ester urethane) urea (PEUU) biomaterial.
- To evaluate the ability of this released inducer to control gene expression in genetically modified cells.
- To assess the spatial control of gene expression using patterned and scaffold-based PEUU systems.
Main Methods:
- A modified ecdysone-responsive gene expression system was transfected into B16 murine cells.
- A synthetic inducer ligand was loaded into PEUU and its release kinetics were studied over one year in vitro.
- PEUU films and porous scaffolds were fabricated with variable inducer loading for spatial gene expression studies, observing green fluorescent protein (GFP) expression.
Main Results:
- PEUU demonstrated extended release of the bioactive inducer ligand over a 12-month period.
- Patterned PEUU films enabled spatially controlled cellular expression of GFP.
- Porous PEUU scaffolds with localized inducer loading resulted in predominant GFP expression in loaded regions.
Conclusions:
- Biomaterial-based controlled release of inducers can effectively regulate gene expression in cells.
- This PEUU system offers precise spatial control over gene activation.
- The technology holds promise for applications in soft tissue repair and regeneration by guiding progenitor cell commitment.
Related Concept Videos
02:33Combinatorial 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...
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...
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...
02:24Regulation 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...
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...
02:24Regulation 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...
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...
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...
02:36RNA 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...