The herpes simplex virus has double-stranded DNA as its genetic material. In order to replicate within the cell the herpes simplex virus’ DNA must enter the nucleus (it enters the nucleus but it does not insert itself into the DNA of the host cell). There in the nucleus, it can be transcribed (making mRNA copies of the DNA) and then translated (turning the viral mRNA into a viral protein) in the cytoplasm. In this way, the virus is able to create new viral proteins, and ultimately entire new viruses, which will can then kill the host cell, in which the virus will go infect other cells (and the cycle continues).
***If you think of the cell as a big factory, the herpes simplex virus is like a person that sneaks into the factory control room, locks themselves in, hooks up their own computer, and uses it to access a few of the factory’s machines to make their own products.
The HIV virus has single-stranded RNA as its genetic material. In order to replicate within the cell, the HIV virus’ RNA must also enter the nucleus of the cell/the control room. However, the human genome is not made from RNA, it’s made from DNA. Therefore, upon entering the cell, the HIV virus must first convert its RNA into DNA. It does this using a special enzyme that it carries called Reverse Transcriptase. Then, the HIV viral DNA will enter the nucleus, just like the herpes simplex virus did. The major difference between the two, however, is that the viral DNA from HIV will actually insert itself into the DNA of the host cell (HSV does not do this, it just enters the nucleus but not the DNA). Then, whenever that cell goes to transcribe/translate its own DNA it will actually transcribe/translate the HIV’s DNA as well, therefore making viral proteins aka more viruses. When these viruses are made, they’re made in a great quantity because a cell is constantly making proteins, therefore it will constantly be making HIV viruses. This ultimately kills the host cell, and the viruses then spread to other cells (and the cycle continues).
***If you think of the cell as a big factory, HIV is like a person that sneaks into the control room and re-codes some of the computers with blueprints for their products, and then whenever the factory is up and running it makes their products.
