What does topoisomerase II do?

Topoisomerase IIα is found at replication forks and remains tightly associated with chromosomes during mitosis [13,39]. Thus, topoisomerase IIα is believed to be the isoform that functions in growth-dependent processes, such as DNA replication and chromosome segregation [7,13].

Does topoisomerase cut DNA?

Topoisomerases cut DNA to release tension created by twists and turns in the double helix. Typically, DNA is negatively supercoiled. This makes it easier to pull the two strands of DNA apart.

What is topoisomerase II alpha?

Topoisomerase IIalpha, an enzyme essential for resolution of DNA replication intermediates, binds telomeres in a TRF1-mediated manner. b-ELE could inhibit the proliferation of HepG-2 cells and interfere with the expression and activity of TOPO I and TOPO IIa.

Why are topoisomerases important?

Topoisomerases. DNA topoisomerases are able to solve topological problems resulting from replication, transcription, recombination, and reorganization of the chromatin. Further on, topoisomerases change the state of supercoiling of the DNA and therefore, have great impact on gene activity.

Is helicase a topoisomerase?

The main difference between helicase and topoisomerase is that helicase unwinds the double-stranded DNA whereas topoisomerase relieves the tension created by helicase. Furthermore, helicase breaks the hydrogen bonds between the two DNA strands while topoisomerase breaks the phosphodiester linkages in the DNA backbone.

What is the function of topoisomerase 1?

Topoisomerase 1 (TOP1) is a highly conserved enzyme that can be found in both prokaryotes and eukaryotes. In the mammalian system, TOP1 is an essential enzyme for normal development [1]. A major function of TOP1 is to relax supercoiled DNA and alleviate the DNA helical constraints [2], [3].

What are the functions of topoisomerases?

Topoisomerases are crucial enzymes for many fundamental aspects of neural function. Their primary functions — to cleave DNA strands in order to provide torsional-stress relief or to untangle replicating DNA — provide essential cellular controls during replication and transcription.