Which enzyme is responsible for relieving tension in the DNA strands during replication?

Topoisomerase is the enzyme responsible for relieving the tension that builds up in DNA strands during replication. As DNA unwinds to allow for replication, the helical structure can create overwinding and twisting in areas ahead of the replication fork. This tension can lead to the formation of supercoils, which can impede further unwinding and replication.

Topoisomerase works by creating temporary cuts in the DNA strands, allowing them to rotate and relieve the tension before rejoining them. This action ensures that the replication process can proceed smoothly without interruptions caused by excessive supercoiling.

DNA Ligase, Primase, and DNA Polymerase each have distinct roles in replication but don't specifically address the tension in DNA strands. DNA Ligase is involved in sealing gaps between Okazaki fragments, Primase synthesizes RNA primers needed for DNA synthesis initiation, and DNA Polymerase is responsible for synthesizing new DNA strands by adding nucleotides to the growing chain. Therefore, Topoisomerase stands out as the crucial enzyme for managing tension during the replication process.