Question

_Please explain, What is the difference between (+)Sense Virus, (-)sense virus, and retroviruses?

_What is the difference between single ORF and multiple ORF, I know one is single reading frame and one is multiple reading frame, but what the use of them in term of genetics of viruses?

Answer 1

+ve sense RNA virus is single stranded whose genetic material is viral m-RNA that encodes codes for proteins. Known to have a positive sense ( 5'-3') RNA genome.Viral m-RNA can be readily translated to proteins.

-ve sense RNA virus is single stranded whose genetic material is viral m-RNA . Known to have negative 3'-5' RNA genome.Viral m-RNA is complementary to m-RNA. Needs to be transcribed into positive sense RNA before translation.

Reterovirus They use special proteins known as reverse transcriptase which allows retroviruses to convert their genomic RNA to DNA which gets inserted in the host cell.