Do RNA viruses have RNA polymerase?

Do RNA viruses have RNA polymerase?

RNA viruses replicate and transcribe their genomes using RNA-dependent RNA polymerases. Reverse-transcribing viruses replicate using reverse transcription, a process for making DNA from RNA templates.

What does negative RNA mean?

Negative-strand RNA virus: Also known as an antisense-strand RNA virus, a virus whose genetic information consists of a single strand of RNA that is the negative or antisense strand which does not encode mRNA (messenger RNA)..

What is positive RNA negative?

Positive-sense viral RNA is similar to mRNA and thus can be immediately translated by the host cell. Negative-sense viral RNA is complementary to mRNA and thus must be converted to positive-sense RNA by an RNA polymerase before translation.

What is the difference between positive and negative-strand RNA?

The main difference between positive and negative sense RNA virus is that positive sense RNA virus consists of viral mRNA that can be directly translated into proteins whereas negative sense RNA virus consists of viral RNA that is complementary to the viral mRNA.

How do positive strand RNA viruses replicate?

Location: Host cell cytoplasm, replication/transcription occurs in membrane invaginations. The neo-synthesized RNA may serve either for replication or translation. For many positive stranded RNA virus, subgenomic RNAs are transcribed, often encoding for structural proteins.

Where do positive sense RNA viruses replicate?

All characterized positive-strand RNA viruses assemble their RNA replication complexes on intracellular membranes, usually in association with membrane vesicle formation or other membrane rearrangements.

What viruses are RNA based?

1.1. RNA Viruses. Human diseases causing RNA viruses include Orthomyxoviruses, Hepatitis C Virus (HCV), Ebola disease, SARS, influenza, polio measles and retrovirus including adult Human T-cell lymphotropic virus type 1 (HTLV-1) and human immunodeficiency virus (HIV).

How are RNA viruses replicated?

RNA viruses replicate their genomes via one of two unique pathways—either by RNA-dependent RNA synthesis, or among the retroviruses, by RNA-dependent DNA synthesis (reverse transcription) followed by DNA replication and transcription.

Are all RNA viruses retroviruses?

Retroviruses (Group VI) have a single-stranded RNA genome but, in general, are not considered RNA viruses because they use DNA intermediates to replicate.

Are all viruses RNA based?

Most viruses have either RNA or DNA as their genetic material. The nucleic acid may be single- or double-stranded. The entire infectious virus particle, called a virion, consists of the nucleic acid and an outer shell of protein. The simplest viruses contain only enough RNA or DNA to encode four proteins.