What is the term for viral RNA that is complementary to mRNA and must be replicated to mRNA before protein production?

The term that describes viral RNA which is complementary to mRNA is known as negative-sense RNA. This type of RNA cannot be directly translated into proteins. Instead, it serves as a template for the synthesis of complementary mRNA through the action of an RNA-dependent RNA polymerase. This process is crucial because the generated mRNA is what subsequently directs the synthesis of proteins by ribosomes in the host cell.

In contrast, positive-sense RNA can be directly translated into proteins without needing to be converted to mRNA. Double-stranded RNA consists of two RNA strands, which may include both positive and negative-sense RNA strands. Single-stranded RNA refers to RNA comprised of just one RNA strand, but it does not specify the orientation or capability of the RNA strand regarding protein synthesis. Thus, negative-sense RNA specifically refers to the type of viral RNA that must undergo replication to produce mRNA before proteins can be synthesized.