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Can virus be killed by inhibiting their protein synthesis?
As a general rule, maximal inhibition of host-cell protein synthesis occurs with viruses that eventually kill their host-cell during the later phases of infection, when viral coat protein is being made in large amounts.
Specifically, viral polymerases use variety of mechanisms to recognize initial binding sites, ensure processive elongation, terminate replication at the end of the genome, and also coordinate the chemical steps of nucleic acid synthesis with other enzymatic activities.
Why do RNA viruses need to encode their own polymerase?
Viruses that spend their entire life cycle in the cytoplasm do not have access to host polymerases and thus need to encode their own polymerases for transcription and replication. RNA viruses have RNA genomes, which can also be either double-stranded (dsRNA) or single-stranded (ssRNA).
Which of the following human diseases is caused by a virus that requires reverse transcriptase?
Reverse transcriptase is central to the infectious nature of retroviruses, several of which cause disease in humans, including human immunodeficiency virus (HIV), which causes acquired immunodeficiency syndrome (AIDS), and human T-cell lymphotrophic virus I (HTLV-I), which causes leukemia.
How do viruses affect protein synthesis?
Competition between virus and host for limiting translation components is influenced by mRNA availability in the cytoplasm of the infected cell. Viruses can interfere with mRNA trafficking, altering mRNA steady-state levels to impair host protein synthesis while stimulating the cellular translation machinery.
How do viruses synthesis proteins?
In conjunction with FV3 transcription, viral protein synthesis occurs in three phases. First, IE proteins are synthesized at the beginning of infection, then DE proteins after 2 h postinfection, and L proteins by 3–4 h postinfection.
What is the function of RNA dependent RNA polymerase?
RNA-dependent RNA polymerase (RdRp) or RNA replicase is an enzyme that catalyzes the replication of RNA from an RNA template. Specifically, it catalyzes synthesis of the RNA strand complementary to a given RNA template.
What is DNA polymerase used for?
DNA polymerase is an enzyme that synthesizes DNA molecules from deoxyribonucleotides, which are the building blocks of DNA. The enzymes play an essential role in DNA replication, usually working in pairs to produce two matching DNA stranges from a single DNA molecule.
Why RNA polymerase has no proofreading?
The enzyme that produces DNA by using an RNA template is reverse transcriptase. This enzyme increases the mutation rate as there is no proofreading activity in this enzyme. The genetic variation in the virus is the result of these mutations.
Why do DNA viruses replicate in the nucleus?
From the perspective of the virus, the purpose of viral replication is to allow production and survival of its kind. Most double-stranded DNA viruses replicate within the host cell nucleus, including polyomaviruses, adenoviruses, and herpesviruses—poxviruses, however, replicate in the cytoplasm.
What happens when retroviruses infect a cell?
A retrovirus is a virus that uses RNA as its genetic material. When a retrovirus infects a cell, it makes a DNA copy of its genome that is inserted into the DNA of the host cell. There are a variety of different retroviruses that cause human diseases such as some forms of cancer and AIDS.
How do viruses cause disease?
Viruses are like hijackers. They invade living, normal cells and use those cells to multiply and produce other viruses like themselves. This can kill, damage, or change the cells and make you sick. Different viruses attack certain cells in your body such as your liver, respiratory system, or blood.