Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Virology + Infectious Agents > Viral Entry > Flashcards

Viral Entry Flashcards

1
Q

What are the 2 main concepts for viral entry?

A
  1. Recognition of host receptor (attachment)
  2. Mechanism to release genome (for eg. in the cytoplasm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

can viruses be passively transported?

A

no too large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how does Viruses find the “right” receptor?

A

Random electrostatic interactions do occur but will not initiate infectious cycle bc receptor is specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is a coreceptor? which type of virus usually uses this?

A

In some cases, a second receptor is very essential for viral entry (never for viruses that infect plants and yeast, usually for humans)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why do cells have these receptors?

A
  • transmembrane surface membrane proteins receptors are used for host cells not just for virus and can be many viruses’ entry points
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the HIV-1 receptor?

A

CD4 and Chemokine receptors (CC and CXC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the poliovirus receptor?

A

PVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the Coxsackie B receptors?

A

PVR and CAR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the adenovirus 2 and 5?

A

CAR + Integren

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the Murine Leukemia virus receptor>

A

Cationic amino acid transporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is th human coronavirus receptor ?

A

amino-peptidase N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the measles virus receptor>?

A

CD46

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the rhinovirus receptor?

A

LDL-receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the SARS-CoV2 entry receptor? what did the mutation of omricron cause?

A

angiotensin-converting enzyme 2 receptor (ACE2) – in humans usually cardiovascular function found in respiratory tract in lungs
- at first the receptor was better in lower resp tract - lungs (follow incubation longer)
- omnicron was receptors in nose (easier transmission)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the Two different modes of attachment? what do they depend on?

A

depdends on outer shell of virus
non enveloped hard shell

enveloped virus (lipid layer + glycoprotein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the details of poliovirus?

family, genome type, symmetry, envelope

A
  • family: picornaviridae
  • ss + RNA
  • 3 viral protiens (1,2,3)
  • icosahedral
  • non-enveloped virus
  • naked virion
17
Q

what is a naked virion?

A

Viruses can “release” their genomes at the plasma membrane

18
Q

how does polivirus entry the host cell?

A
  1. VP1 interacts with receptor PVR making conformational change
  2. makes pore on host cell surface
  3. polivirous injects RNA directly across membrane
19
Q

what is an example of an envelope virus? what is its glycoprotein? what does the glycoprotein interact with on host?

A

influenza virus
- has hemagglutinin viral envelop glycoprotein that binds to cell host receptor (sugar sialic acid)

20
Q

what are the types of sialic acid? What do each type mean?

A

2-6 linkage btwn sialic acid and galactose preferred by human influenza virus

2-3 linkage preferred by avian influenza virus

21
Q

where are the 2 types of sialic acid receptors found?

A

Sialic acid receptors with 2-6 linkages in upper and lower tract. Will bind human influenza viruses

Sialic acid receptors with 2-3 linkages in lower tract.
Will bind avian influenza viruses

22
Q

can humans be infected with avian influenza virus?

A

Very deep breath of many virions; but possible

23
Q

What are the 3 ways of virus endocytosis? what type of transport?

A
  1. phagocytosis (solid particle intake in a phagosome)
  2. pinocytosis (extracellular fluid in vesicle)
  3. receptor mediated endocytosis (receptor attaches to virus and have coated vescicle from coated pit on inner layer of cell)

ACTIVE TRANSPORT

24
Q

what is a trigger for viral genome release?

A

pH difference in cell

25
Q

where are the 3 locations that virisus can release their genome? what are the pH at each location?

A
  1. inject (like polio) -7 pH
  2. early endosome - 6.5-6 pH
  3. late endosome - 5.5-5 pH
26
Q

why are viral genomes released at different locations?

A

depending on virus and the protein’s preferred environment

27
Q

What type of virus is a reovirus? how is it entering the cell?

A
  • non-enveloped entry
  • integrin or salic acid receptor
  • receptor mediated endocytosis
  • Early endosome causes loss of capsid
  • Late endosome causes holes creating in late endosome releasing core with cysteine proteases called cathepsin from host cut through layers of reovirus
28
Q

what is type of virus measles virus? family?

A
  • Paramyxoviridae
  • enveloped virus
  • coreceptor required
  • fusion events depend on pH (acitvate viral proteins in acidic environment causing fusion and stretching of viral glycoproteins
29
Q

how does ebola virus enter?

A
  • NPC1 cholesterol transporter
  • late endosome
  • virus expresses various sugars on top that inhibit NPC-1 interaction
  • cysteine proteases cathepsin cleave surface molecules removing hindering sugar molecules so that ebola virus can bind to NPC 1

Virology + Infectious Agents (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions