Final answer:
The helicase enzyme binds to origins of replication in DNA and unwinds it, which is essential for initiating the replication process. It works in concert with other proteins to form the primosome, as well as topoisomerases like DNA gyrase to manage DNA supercoiling.
Step-by-step explanation:
A multi-protein complex, the helicase binds to origins and unwinds the DNA in those regions. This process is crucial for DNA replication. Helicase is responsible for opening up the DNA helix at the origin of replication, allowing for the formation of Y-shaped structures known as replication forks. Concomitantly, single-strand binding proteins (SSBs) coat the DNA strands to prevent rewinding, while topoisomerase, particularly DNA gyrase in bacteria, relaxes the supercoiling of the chromosome. In eukaryotic cells, apart from helicase, additional proteins and multiprotein complexes are involved during replication initiation. These proteins include those that interact with histones to relax the nucleosome structure and allow access to the DNA, as well as those involved in the formation of the primosome, which is a complex necessary for the synthesis of RNA primers.