Chapter 14B: SARS-CoV-2 and COVID-19

Question 1

SARS-CoV-2

Answer 1

Severe Acute Respiratory Syndrome Coronavirus-2
Belongs to Coronaviridae
Newly emerging
Highly transmissible
Infecting epithelial and many other types of cells

Question 2

31 December 2019

Answer 2

Chinese health officials notified WHO of severe cases of an unusual viral pneumonia in Wuhan

Question 3

7 January 202

Answer 3

Pathogen identified as novel coronavirus

Question 4

11 February 2020

Answer 4

WHO named COVID-19 and SARS-CoV-2

Question 5

11 March 2020

Answer 5

WHO declared the outbreak a pandemic

Question 6

Virion Structure

Answer 6

Large(100-160 nm in diameter)
Enveloped
Spikes on surface -> crown-like
Nucleocapsid: helical symmetry
(+) ssRNA genome

Question 7

Major Structural Proteins

Answer 7

S, E, M, N

Question 8

S protein

Answer 8

Spike

bind to the host cell through its RBD (receptor-binding domain)

Question 9

E Protein

Answer 9

Envelope

Help assembly and release virions

Question 10

M Protein

Answer 10

Membrane

work with E, N, and S; play major role in RNA packaging

Question 11

N protein

Answer 11

Nucleocapsid

package viral RNA into nucleocapsid

Question 12

Genome Structure

Answer 12

(+) ssRNA
About 30kb
5' cap, 3' poly-A tail
12 ORFs: RdRp, proteases, other NSPs
Other ORFs
High mutation rate

Question 13

Anti-receptor

Answer 13

S-protein

Question 14

Receptor

Answer 14

ACE2 (angiotensin-converting enzyme 2) widely distributed in various tissues

Question 15

TMPRSS2

Answer 15

facilitate viral entry

Question 16

Entry and uncoating

Answer 16

Membrane fusion

Endocytosis and then membrane fusion

Question 17

Translation of ORF1a and ORF1b

Answer 17

(+)RNA-> RdRp, other NSPs

Question 18

Subgenomic Transcription

Answer 18

(-) RNA -> subgenomic (+)RNAs

Question 19

Translation

Answer 19

Subgenomic(+)RNAs-> S, M, E at ER; N in cytoplasm

Question 20

ERGIC

Answer 20

ER-to-Golgi Intermediate Compartment (as budding site

Question 21

Assembly

Answer 21

nucleocapsid buds into ERGIC with S, M, E -> virion

Question 22

COVID-19

Answer 22

Coronavirus disease of 2019

Question 23

COVID-19 progression

Answer 23

1. Early infection: no or mild symptoms
2. Pulmonary phase: pneumonia and disseminated inflammation
3. Hyperinflammation phaseL Acute Respiratory Distress Syndrome, multiorgan failure