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Condensins are large protein complexes that use ATP to fuel the assembly of chromosomes during mitosis. They transform the tangled, shapeless mass of post-interphase DNA into individualized chromosomes by compacting, organizing, and segregating chromosomal DNA.
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Condensins

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Related Experiment Video

Updated: Jun 10, 2026

Synthetic Condensates and Cell-Like Architectures from Amphiphilic DNA Nanostructures

Synthetic Condensates and Cell-Like Architectures from Amphiphilic DNA Nanostructures

Published on: May 31, 2024

DNA condensation by pH-responsive polycations.

Andreia F Jorge¹, Rita S Dias, Jorge C Pereira

¹Department of Chemistry, Coimbra University, Rua Larga, 3004-535 Coimbra, Portugal.

Biomacromolecules

|August 20, 2010

Summary

This summary is machine-generated.

pH significantly impacts DNA-polyethylenimine (PEI) complex formation. Complex properties like size and charge vary non-monotonically with pH, revealing critical factors in condensation behavior.

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Published on: January 19, 2019

Area of Science:

Biochemistry
Materials Science
Physical Chemistry

Background:

Polyethylenimine (PEI) is a cationic polymer used in gene delivery.
DNA-polyethylenimine (PEI) complexes are crucial for gene therapy applications.
Understanding pH effects on complex formation is vital for optimizing delivery systems.

Purpose of the Study:

To investigate the influence of pH on DNA-PEI complex formation.
To characterize the physical and electrical properties of these complexes across a range of pH values.
To elucidate the role of linear charge density and chain number in DNA condensation.

Main Methods:

Potentiometric titration of PEI to determine acid-base behavior.
Precipitation assays to assess complex formation.
Agarose gel electrophoresis to evaluate DNA mobility.
Photon correlation spectroscopy for size analysis.
Zeta potential measurements for surface charge determination.

Main Results:

DNA-PEI complex properties (mobility, size, electrical properties) showed non-monotonic trends with pH.
Complexes exhibited strong binding and larger size at pH 4, versus smaller, more uniform populations at pH 8.
Charge inversion was observed across all studied pH values, even below charge neutralization.
Both linear charge density and the relative number of PEI chains influenced condensation.

Conclusions:

pH is a critical parameter controlling DNA-PEI complex formation and properties.
Non-trivial pH-dependent trends highlight the complexity of polycation-polyanion interactions.
These findings provide insights for designing effective gene delivery vectors by tuning pH conditions.