not_my_usual_name OP t1_jc3gw7y wrote on March 13, 2023 at 7:37 PM

Reply to comment by babar90 in How does viral RNA encode both the capsule and the RNA? by not_my_usual_name

This is interesting. My understanding was always that the viral RNA is seen as RNA coming from the cell's DNA, and the cell's protein assembling machinery would assemble a virus according to the virus' RNA. You're saying that the virus' RNA actually has the cell's machinery assemble a virus factory "replication complex"?

Presumably in the replication complex, there's some molecule producing viral RNA. Does it do that by looking at and copying the original strand of RNA (or copies)? If not, then was the RNA production machine built "knowing" how to make the viral RNA? I'd think that involves some compression, which is what I'm most curious about.

babar90 t1_jc3jiw3 wrote on March 13, 2023 at 7:54 PM

All the translation (making of proteins) is done by the cell's ribosomes (this for almost every viruses) from mRNA strands as the cells do everydays to make proteins.

But the replication and transcription (making copies of the full length RNA genome and some mRNA copied from parts of it) is achieved by a viral polymerase, a RdRp.

This is for RNA viruses. Many DNA viruses do something along the same lines, but some do not and make their genome enter the cell nucleus to exploit either its DNA replication machinery or its DNA->RNA transcription machinery, or both.

Retroviruses are some kind of hybrid between the two strategies.