Related Experiment Video
Updated: Jun 1, 2026
06:48
CD Spectroscopy to Study DNA-Protein Interactions
Published on: February 10, 2022
Atomic force microscopy studies on circular DNA structural changes by vincristine and aspirin
Zhongdang Xiao1, Lili Cao, Dan Zhu
1State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China. zdxiao@seu.edu.cn
Methods in Molecular Biology (Clifton, N.J.)
|June 11, 2011
Summary
This study demonstrates Atomic Force Microscopy (AFM) as a powerful tool for visualizing DNA-drug interactions. Researchers imaged circular DNA treated with vincristine and aspirin, revealing structural changes.
Area of Science:
- Biophysics
- Molecular Biology
- Nanotechnology
Background:
- Understanding DNA-drug interactions is crucial for developing new therapeutics.
- Atomic Force Microscopy (AFM) offers high-resolution imaging capabilities for biological molecules.
Purpose of the Study:
- To present methods for studying DNA-small molecule drug interactions using AFM.
- To demonstrate the detailed imaging of circular DNA incubated with vincristine and aspirin.
Main Methods:
- Utilized Atomic Force Microscopy (AFM) for high-resolution imaging of DNA.
- Immobilized circular DNA fragments onto a mica surface for stable imaging.
- Investigated the effects of varying concentrations of vincristine and aspirin on DNA structure.
Main Results:
- Successfully imaged DNA-drug complexes, showing detailed conformations and structural changes.
- Demonstrated the critical role of DNA immobilization and tip-sample force in successful imaging.
- Quantitatively described alterations in circular DNA structure upon drug incubation.
Conclusions:
- Atomic Force Microscopy (AFM) is a powerful and effective technique for studying DNA-drug interactions at the molecular level.
- The presented methods enable quantitative analysis of structural changes in DNA induced by small molecule drugs.
Related Concept Videos
01:17Studying the Cytoskeleton
The cytoskeletal architecture can be studied using different microscopic and biochemical techniques. Electron microscopy was instrumental in discovering the cytoskeletal architecture around the 1960s, which allowed obtaining structural information at a high-resolution level. However, the sample preparation procedure often limits this ability in biological samples. Several protocols have been developed over the years to optimize sample preparation. In one of the protocols known as rotary...
00:55DNA Helicases
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
01:10Drugs that Destabilize Microtubules
Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...