Related Experiment Video
Updated: Jan 23, 2026
12:05
Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies
Published on: March 6, 2013
14.6K
Peptide Sequence-Dependent Gene Expression of PEGylated Peptide/DNA Complexes
Mikiko Ueno1, Satoshi Yamauchi1, Daiki Kumekawa1
1Department of Materials Engineering, Graduate School of Engineering , The University of Tokyo , Hongo 7-3-1 , Bunkyo-ku, Tokyo 113-8656 , Japan.
Molecular Pharmaceutics
|June 8, 2019
Summary
Synthesized PEG-peptides with cysteines form cross-linked polyplex micelles (PMs) for plasmid DNA (pDNA) delivery. Cysteine placement influences pDNA release and gene expression efficacy in cell-free and cell-based systems.
Area of Science:
- Biotechnology
- Polymer Chemistry
- Gene Delivery Systems
Background:
- Developing effective non-viral gene delivery vectors is crucial for gene therapy.
- Polyplex micelles (PMs) offer a promising platform for DNA encapsulation and delivery.
- Responsive elements are needed to control DNA release at target sites.
Purpose of the Study:
- To synthesize and characterize oligolysine-based PEG-peptides for formulating plasmid DNA (pDNA) polyplex micelles (PMs).
- To investigate the impact of cysteine residue placement on PM morphology, pDNA release, and gene expression.
- To evaluate the performance of these PMs in both cell-free and cell-based gene expression systems.
Main Methods:
- Synthesis of PEG-peptides with varying cysteine placements (N-terminal, center, C-terminal).
- Formation and characterization of polyplex micelles (PMs) encapsulating luciferase-coding pDNA using Transmission Electron Microscopy (TEM).
- Assessment of pDNA release under reductive conditions via gel retardation assays and evaluation of gene expression in cell-free and HeLa cell systems.
Main Results:
- All PEG-peptides condensed pDNA into rod-like or toroidal PMs, with morphology influenced by peptide sequence and length.
- Cysteine-installed PEG-peptides demonstrated reductive environment-responsive pDNA release compared to cysteine-free counterparts.
- A clear relationship between amino acid sequence and in vitro gene expression efficacy was established in a cell-free system, with variations observed in cell-based assays.
Conclusions:
- Oligolysine-based PEG-peptides with strategically placed cysteines can form functional PMs for pDNA delivery.
- Cysteine incorporation enables environment-responsive pDNA release, enhancing vector control.
- The study highlights the importance of correlating cell-free and cell-based assay results for optimizing gene delivery vector design.
More Related Videos
07:53Peptides from Phage Display Library Modulate Gene Expression in Mesenchymal Cells and Potentiate Osteogenesis in Unicortical Bone Defects
Published on: December 10, 2010
18.5K
08:48Peptide-derived Method to Transport Genes and Proteins Across Cellular and Organellar Barriers in Plants
Published on: December 16, 2016
11.0K
Related Concept Videos
02:43Peptide Bonds
82.5K
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
82.5K
01:42What is Gene Expression?
195.1K
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...
195.1K
01:36What is Gene Expression?
11.1K
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...
11.1K
02:51mRNA Stability and Gene Expression
6.6K
The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
Cis-acting Elements involved in mRNA stability
6.6K
01:58Cell Specific Gene Expression
16.3K
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
16.3K
02:35Chromatin Position Affects Gene Expression
24.7K
Chromatin is the massive complex of DNA and proteins packaged inside the nucleus. The complexity of chromatin folding and how it is packaged inside the nucleus greatly influences access to genetic information. Generally, the nucleus' periphery is considered transcriptionally repressive, while the cell's interior is considered a transcriptionally active area.
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the...
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the...
24.7K