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Updated: May 12, 2026
10:46
Motility of Single Molecules and Clusters of Bi-Directional Kinesin-5 Cin8 Purified from S. cerevisiae Cells
Published on: February 2, 2022
Kinesin KIFC1 actively transports bare double-stranded DNA
Francesca Farina1, Paolo Pierobon, Cédric Delevoye
1Physico-Chimie-Curie/UMR168 Institut Curie, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, 75231 Paris, France.
Nucleic Acids Research
|April 2, 2013
Summary
Exogenous DNA transport to the nucleus is active, utilizing cytoskeleton filaments and driven by the molecular motor kinesin KIFC1. This finding is crucial for gene and molecular therapy development.
Area of Science:
- Molecular biology
- Cell biology
- Biophysics
Background:
- Exogenous DNA is utilized in gene and molecular therapies.
- The mechanism of nuclear entry for exogenous DNA remains unclear.
Purpose of the Study:
- To investigate the intracellular transport mechanism of exogenous short DNA molecules.
- To identify the molecular players involved in DNA translocation within eukaryotic cells.
Main Methods:
- In-cell single-molecule imaging to observe DNA motion in the cytoplasm.
- In vitro motility assays using cell extracts to monitor DNA movement along cytoskeleton filaments.
- Protein precipitation and mass spectrometry to identify DNA-binding proteins.
- Kinesin KIFC1 depletion experiments to assess its role in DNA transport.
Main Results:
- Exogenous DNA molecules exhibit active transport along cytoskeleton filaments within the cytoplasm.
- Microtubule-associated motors are implicated in this active DNA transport.
- Mass spectrometry identified kinesin KIFC1 as a preferential DNA-binding motor protein.
- Depletion of kinesin KIFC1 significantly reduced DNA motion, confirming its role.
Conclusions:
- Intracellular DNA transport is an active process mediated by molecular motors.
- Kinesin KIFC1 plays a significant role in the cytoplasmic movement of exogenous DNA.
- Understanding this transport mechanism can inform the development of gene and molecular therapies.
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