15 million people were self-employed in 2015, or 10.1 percent of all U.S. workers. Self-employment continues to be an important source of jobs in the United States. In 2015, 15.0 million people, or 10.1 percent of total U.S. employment, were self-employed, including those who had incorporated their businesses and those who had not.
DNA helicase is the enzyme that unwinds the DNA double helix by breaking the hydrogen bonds down the center of the strand. It begins at a site called the origin of replication, and it creates a replication fork by separating the two sides of the parental DNA.
In eukaryotes they are not referred to as restriction enzymes, just endonucleases. An example of an endonuclease in eukaryotes is Apn1, isolated from yeast. This enzyme helps prevent DNA damage from environmental agents.  Another common enzyme family called the topoisomerases (DNA Gyrase) has endonuclease activity.