General virology 2

Question 1

What are the stages of virus infection of a host cell?

Answer 1

Adsorption

Penetration

Uncoating

Synthesis of viral products

Relase of virions from the cell.

Question 2

What are some pattern recognition receptors in cells?

Answer 2

Membrane TLRs and Endosomal TLRs

RLRs: Rig-Like Receptors. Intracellular PRRs, which recognize viral patterns

NLRs: NOD-like receptors: recognize bacterial peptidoglycans intracellularly

PKR: Detects double stranded RNA, and then inhibits protein synthesis by phosphorylating eIF-2 (eukaryotic inititiation factor 2 alpha), and can activate pro-apoptotic pathways.

Cytoplasmic DNA receptors

Question 3

What signaling molecules are released by cells one they have detected a viral infection in themselves?

Answer 3

Interferon alph and Interferon beta

They signal to nearby cells and activate anti-viral proteins expression (AVPs)

Question 4

What is the major signalling pathway activated by IFNs?

Answer 4

Jak/Stat pathway, which initiates an antiviral state and syntehsis of AVPs.

Question 5

What are some intracellular antiviral proteins?

Answer 5

PKR- protein kinase R detects dsRNA and activates apoptotic pathways, inhibits protein translation.

RNAse L: the interferon inducibel OAS-RNase L pathway Activated by Interferon signaling, which in turn activates oligoadenylate synthetase. and Oligoadenylate will dimerize in the presence of viral RNA to dimerize and activate RNAse L, an RNAse that will destroy all RNA within a cell, both viral and host.