Retroviridae

Question 1

What feature of retroviridae is responsible for its name?

Answer 1

Reverse transcriptase

Question 2

Retroviruses cause what 3 broad illnesses?

Answer 2

cancer, immunosuppression, inmmunodeficiency

Question 3

What is reverse transcriptase?

Answer 3

RNA-dependant polymerase

Question 4

5 retroviruses of veterinary importance

Answer 4

Equine infectious anemia virus
bovine leucosis virus
jaagsiekte virus of sheep
retroviruses of chickens
Rous sarcoma virus

Question 5

3 human diseases caused by retroviruses

Answer 5

lymphomas
leukemia
AIDS

Question 6

Do retroviruses have an envelope?

Answer 6

Yes

Question 7

Retrovirus genome

Answer 7

Diploid, 2 copies of single stranded POSITIVE sense RNA

Question 8

How do retroviruses integrate into host genome?

Answer 8

integrase

Question 9

What does integration of host genome imply clinically?

Answer 9

alteration of genome
in/activation of genes
acquisition of host genome

Question 10

Retrovirus morphology

Answer 10

Spherical virons, envelope of LiBil
Projetions of glycoprotein
protein matrix under envelope

Question 11

Type A specific morphologhy

Answer 11

thick shell with hollow, electron lucent center

Question 12

Type B specific morphologhy

Answer 12

Round but eccentrically positioned inner core

Question 13

Type C specific morphologhy

Answer 13

plasma membrane assembly

Central symmetrically place core

Question 14

Type D specific morphologhy

Answer 14

cytoplasm assembly
via Type A intermediate
budding with cylindrical core

Question 15

Viron size

Answer 15

80-100 nm

Question 16

RNA genome size

Answer 16

7-11kb

Question 17

T/F Virons are easily inactivated by lipid solvents and heating

Answer 17

True

Question 18

Are the viron resistant to X-rays and UV rays?

Answer 18

yes

Question 19

How many molecules of reverse transcriptase are included in a viron?

Answer 19

~30

Question 20

Is reverse transcriptase (RT) required for replication?

Answer 20

yes

Question 21

What does the gag gene encode?

Answer 21

Capsid
Nucleocapsid
Matrix

Question 22

pol gene?

Answer 22

RT

Integrase

Question 23

env gene?

Answer 23

envelope proteins
surface
transmembrane

Question 24

pro gene?

Answer 24

protease

Question 25

What is an alpharetrovirus?

Answer 25

Simple retrovirus with type C morphology

Question 26

Alpharetroviruses of concern

Answer 26

avian leukosis and sarcoma virus

Question 27

Genes found in alpha

Answer 27

gag, pro, pol, env

Question 28

2 types of Alpharetroviruses

Answer 28

exogenous

endogenous

Question 29

Which of the 2 types of Alpharetroviruses is transmitted vertically?

Answer 29

endogenous

Question 30

Betaretrovirus morphology

Answer 30

simple type B or type D