Lecture 5 Flashcards
What are the two main aspects of viral entry?
- Recognition of the host receptor (attachment).
- A mechanism to release the genome.
What is a resistant virus?
A virus that is not susceptible because it does not have the required receptor/co-receptor for a virus. It may, however, still be permissive.
Can a virus recognize multiple receptors?
Can a receptor recognize multiple viruses?
Yes and yes
Which subunit of poliovirus is important for membrane insertion?
VP1
What is hemagglutinin?
A viral envelope glycoprotein that can be recognized by host cell receptors in Influenza.
What is sialic acid?
A sugar in the host cell receptor that is a receptor for hemagglutinin in Influenza. Sugar-sugar interaction because hemagglutinin is a glycoprotein.
What type of sugar linkages occur in the two types of influenza (an enveloped virus) that determines specificity? Which does each type of virus prefer?
Sugar-sugar linkages: 2-3 or 2-6 linkages both occur
Human influenza: 2-6 linkages
Avian influenza: 2-3 linkages
What is active transport in the mechanism of release of a virus in the host cell?
When a virus is admitted into the cell after recognition of a receptor, it is transported through the cell in a vesicle which moves along a track by a molecular motor.
What is the most common entry mechanism of a virus?
Receptor-mediated endocytosis
What are cathepsins?
Cysteine proteases involved in the late endosome, activated by the pH of 5.5-5.0. They puncture holes in the endosome, releasing the genomic contents of the reovirus.
