HIV I

Question 1

Is CMV an STI?

Answer 1

yes!

Question 2

where is HIV 1 and 2 from

Answer 2

HIV 1: Chimpanzee

HIV 2: Sooty Mangabey

Question 3

how does food handling lead to transmission of HIV

Answer 3

person who is HIV+ handling food with open lesions on hands and no gloves can transmit virus to food which someone will eat

Question 4

type of virus is HIV

Answer 4

retrovirus - RNA virus

Question 5

how do retroviruses replicate

Answer 5

they make an RNA dependent DNA polymerase to turn their genome into an intermediate DNA in order to replicate

Question 6

how can the replication of these RNA retroviruses be inhibited

Answer 6

actinomycin D

Question 7

the first pathogenic human retrovirus

Answer 7

human T cell leukemia

Question 8

which of the HIV strands is most common

Answer 8

HIV 1 with subtype B

Question 9

subfamily of HIV

Answer 9

lentivirinae

Question 10

what are the characteristics of viruses that fall under subfamily lentivirinae

Answer 10

slow onset of disease, neurological disorders and immunosuppression, D type, cylindrical nucleocapsid core

Question 11

what are the env genes that are encoded by retrovirus group not lentivirinae

Answer 11

HERV-K (HML-2) and primate evolution syncytins

Question 12

what do simple retroviruses encode

Answer 12

gag, pol, and env genes (PEG)

Question 13

what do complex viruses encode

Answer 13

accessory genes such as HIV: tat, rev, nef, vif, vpu

Question 14

what are the functions of the genes that simple retroviruses encode

Answer 14

gag - group specific antigen (core and capsid proteins)
pol - polymerase (reverse transcriptase, protease, integrase)
env - envelope (glycoproteins)

Question 15

describe the genome of class VI viruses

Answer 15

retroviruses

RNA, ss, + sense, RT

Question 16

how many copies of RNA does HIV virus have and describe them

Answer 16

2 copies of +RNA which are non infectious

Question 17

what generates the ds provirus and what is function of provirus

Answer 17

reverse transcriptase makes the ds provirus
provirus gets incorporated into host genome to be used as template for the viral RNA which makes structural and non structural proteins

Question 18

how many orfs and proteins does HIV have

Answer 18

9 orfs and 15 proteins

Question 19

what allows HIV virus to bind and enter host cell and describe what these things are

Answer 19

gp120 - docking glycoprotein

gp41 - transmembrane glycoprotein

Question 20

the CD 4 T cell receptors first bind the HIV virus. subsequently what are the chemokine receptors on the CD4T cells that bind allowing entry of HIV genome into the cell

Answer 20

CXCR4/ CCR5

Question 21

big overview of what occurs with HIV replication

Answer 21

binding and fusion, reverse transcriptase, integration, transcription, assembly, budding

Question 22

what occurs in the budding and fusion and reverse transcription phase of HIV replication

Answer 22

budding and fusion: HIV binds to the CD 4 receptors and co-receptors (CXCR4/CCR5) to fuse with the host cell to release RNA into host cell

reverse transcriptase (RNA dependent DNA polymerase): converts ssRNA HIV to dsDNA HIV (aka provirus) in the cytoplasm

Question 23

what occurs in the integration and transcription phase of HIV replication

Answer 23

integration: newly formed dsDNA HIV aka provirus enters into the nucleus and integrase helps it integrate into host cell’s genome; this establishes a reservoir/establishes life long infection; provirus can remain latent for many years then activated
transcription: host cell receives signal to become active then provirus uses host cell’s RNA polymerase to copy the genome. RNA goes to cytoplasm where RNA is made into viral proteins

Question 24

what occurs in the assembly and budding phase of HIV replication

Answer 24

assembly: HIV protease cuts HIV proteins into smaller individual proteins which combine with HIV genome to make new virus particle
budding: newly formed virus buds from host cell taking part of cell’s outer envelope which contains HIV glycoproteins gp120 and gp41 which it needs to attach to other host cell’s receptors and co receptors

Question 25

how is HIV transmitted

Answer 25

through infected individual’s blood (needles), semen, or vaginal fluid

Question 26

how long does HIV survive outside the body

Answer 26

not very long

Question 27

increased risk of STI infections if one has HIV and increased risk of contracting HIV if one has STI – just know that

Answer 27

thank V-nasty!

Question 28

where is most of the population living with HIV

Answer 28

sub saharan Africa

Question 29

where are there low percentages of transmission of HIV in some areas and not others

Answer 29

areas where there are high antiretroviral therapy