It is incorporated into the cell's genome to produce something called a provirus or a proviral DNA. The profiral DNA is the genome, it's the DNA of that whole cell that has incorporated that viral DNA that we injected. And the great thing about these retroviruses is most of the time they don't actually kill that cell, at least not immediately. So retroviruses can be very effective vectors, they can be used to bring four recombinant DNA molecules into the host animal cell and can incorporate it that viral DNA molecule that we want to into that host genome without actually killing that cell. Now once we incorporate that DNA molecule into the host genome, that DNA is known as a provirus or proviral DNA and we can now use the cell, can use the proviral DNA to basically synthesize the proteins and one of these proteins would be the protein that is encoded by that viral DNA molecule that we injected. So this is described by the following diagram.