Topoisomerase IIα C-terminus DNA Purification


  • Maryo Toma


As humans, it is essential that our cells replicate as we about our lives. This occurs through DNA replication, which is a process that is dependent upon the topoisomerase enzyme. When DNA is replicated, a lot of torsional strain is put on the double helix as it is twisted. If too much of this strain occurs, the helix cannot move forward with the replication process. This is where the topoisomerase enzyme comes in, making cuts in the DNA, releasing the tension, and then religating the ends. Focusing specifically on Topoisomerase II, there are two kinds, α and β. Topoisomerase IIβ is in most of our body’s cells and is involved in neural development. On the other hand, in cancerous cells, Topo IIα is primarily observed. Cancerous cells are rapidly proliferating cells and undergo many more rounds of DNA replication than normal cells. Therefore, compounds can be used to inhibit the functioning of topoisomerase IIα inside cancerous cells, thereby hindering DNA replication, and preventing them from spreading. However, there is a catch. Topoisomerase IIα and IIβ both have very similar structures, and drugs used to inhibit one could inhibit the other. By purifying a truncated version of the Topoisomerase IIα enzyme that only contains the portion of its DNA sequence that is different from that of topoisomerase IIβ’s, we can develop compounds that are specific to this cancer involved topoisomerase. The process of how we go about purifying the DNA the codes for this truncated enzyme will be discussed.