The recent series of posts on polymerase error rates and viral evolution has elicited many excellent and thought provoking comments from readers of virology blog. Here is one that I had not thought of before, and which I’ll use on an exam in my virology course: Here’s a tough question. In the follow up blog …
Why don’t DNA based organisms discard error repair? Read More »
The capacity of RNA viruses to produce prodigious numbers of mutations is a powerful advantage. But remember that selection and survival must balance genetic fidelity and mutation rate. Many mutations are not compatible with viral replication. Consequently, if mutation rates are high, at some point accumulating base changes lead to lethal mutagenesis – the population …
Now that we have examined influenza viral RNA synthesis, it’s a good time to step back and look at a very important property of this step in viral replication. All nucleic acid polymerases insert incorrect nucleotides during chain elongation. This misincorporation is one of the major sources of diversity that allows viral evolution to take …
In episode #25 of the podcast This Week in Virology, Vincent, Alan, and Luis Villarreal talk about rabies in Viet Nam and Angola, needle-stick infections with ebolavirus and West Nile virus, and viral evolution. Click the arrow above to play, or right-click to download TWiV #25 or subscribe in iTunes or by email.
Are viruses living entities? I don’t believe so, but it’s an engaging question for debate. On a recent episode of “This Week in Virology” we concluded that it’s somewhat of a futile argument because everyone has their own view; perhaps our time is better spent studying viruses than discussing whether or not they are alive. …
The rapid clearance of acute viral infections is a consequence of robust host defenses. Survivors of acute infections are usually immune to infection with the same virus. If the immune response is so effective, why do some viral infections – such as the common cold or influenza – occur repeatedly? Acute infections recur because selection …
Antigenic variation explains recurring acute infections Read More »
