Topoisomerase
Why does Topoisomerase Cut DNA?
Topoisomerase cuts DNA to relieve torsional stress and maintain DNA topology during cellular processes.
What do Topoisomerase 1 and 2 do?
Topoisomerase 1 and 2 both regulate DNA topology, but Topoisomerase 1 primarily introduces single-strand breaks to alleviate torsional stress, while Topoisomerase 2 introduces double-strand breaks to regulate DNA supercoiling and facilitate processes like DNA replication and segregation.
What is the Function of Topoisomerase?
Topoisomerases play a crucial role by relieve torsional stress and prevent overwinding or underwinding of the DNA helix by creating transient breaks in one or both DNA strands.
What is the Difference Between Topoisomerase and Helicase?
Topoisomerases regulate DNA topology by introducing transient breaks to relieve torsional stress, while helicases unwind the DNA double helix by disrupting hydrogen bonds.
Does Topoisomerase break Phosphodiester Bonds?
Yes, Topoisomerases break and then rejoin the phosphodiester bonds in DNA strands.
Where is Topoisomerase Used in Medicine?
Topoisomerases are widely used for cancer treatment as they inhibit Topoisomerase activity in religation step and ultimately result in cell death.
What are the Examples of Topoisomerases?
Bacterial and archaeal Gyrase is an example of Type II Topoisomerase. This enzyme introduces negative supercoiling of DNA helix and helps in the advancement of replication fork.
What is the Difference between Topoisomerase I and II?
Topoisomerase I resolves DNA supercoiling by creating a transient single-strand break, while Topoisomerase II introduces a double-strand break and passes another DNA segment through it, altering DNA topology.
What is the Mechanism of Action of Topoisomerase?
All topoisomerases target the phosphodiester backbone of DNA to produce a strand break.
Topoisomerase
Topoisomerases are nucleases that break the phosphodiester bonds in DNA reversibly. Topoisomerases function to relieve the positive supercoiling that arises from DNA unwinding mediated by helicases during replication. The first topoisomerase was discovered by James Wang in 1971 from Escherichia coli. Understanding the Topoisomerase types and structure helps us learn the complicated mechanisms underlying DNA dynamics. In this article, we will cover Topoisomerase – structure, function, types, and more.
Table of Content
- What is Topoisomerase?
- Types of Topoisomerase
- Functions of Topoisomerase
- Topoisomerase in DNA Replication
- Topoisomerase Inhibitors
- Topoisomerase vs Helicase
- Difference Between Topoisomerase and Gyrase