Virus

Question 1

Name the nine genes in hiv’s rna strand

Answer 1

Gag, pol, env, rev, tat, nef, vif, vpu, vpr

Question 2

What are the two most common co receptors on the surface of a CD4 presenting cell

Answer 2

CCR5 and CXCR4

Question 3

What is the parts of the life cycle

Answer 3

Attachment, fusion, reverse transcriptase, integrate, transcriptase, assembly and budding

Question 4

Name the four categories to describe the nine HIV genes

Answer 4

Structural
Catalytic
Regulatory
Accessory

Question 5

What are the structural genes

Answer 5

Gag (group specific antigen) - p17,p24 and p7 which codes for synthesis of the core proteins including p24

Env (envelope) - gp120 and gp41 which codes for construction of the envelope genes to assist in attaching the virus to the co receptors on the surface of cd4 presenting cells

Question 6

What are the catalytic genes

Answer 6

Pol - (polymerase) this gene codes for the construction of protease, reverse transcriptase and integrase

Question 7

What are the regulatory genes

Answer 7

Tat - (trans-activator of transcription) which accelerates viral replication

Rev - (regulator of expression of viral particles) which switches replication cycle to the production of whole virus particles

Question 8

What are the Accessory genes

Answer 8

vpu (viral protein unique) - induces the degradation of CD4 viral receptor and prevents CD4 env binding to the endoplasmic reticulum

vif (viral infectivity factor) - determines the infectivity of cell free virus

vpr (viral protein R) - facilitates the transport of HIV DNA into the cell nucleus and regulates the cell cycle

nef (negative regulatory factor) - contributes to the virulence of HIV (a strain of virus with a deletion of the nef gene has reduce immunodeficiency)

Question 9

gag polyproteins p55 get cleaved by protease enzyme into what type of proteins

Answer 9

matrix proteins (p17), capsid proteins (p24) and nucleocapsid proteins (p7)

Question 10

how long does it take for HIV infected cells to occur after innoculation

Answer 10

within 2 days in lymph nodes and 5 days in plasma, this is why the longest timeframe for nPEP to be of effect is 72hrs

Question 11

what type of cells have CD4 molecules that bind with gp120

Answer 11

T cells, macrophages and microglial cells

Question 12

what HIV viral enzyme plays a key role in viral replication

Answer 12

reverse transcriptase

Question 13

What doe HLA -B stand for

Answer 13

Human Leukocyte Antigen B (gene)

Question 14

What is the HLA-B gene that is related to Abacavir sensitivity

Answer 14

HLA-B 5701

Question 15

what is the rate of viral replication and infection of CD4 cells

Answer 15

over one billion viral particles are produced each day which leads to the body producing vast quantities of T helpers cells but eventually the virus ability to damage the immune system exceeds the bodies capacity to fight HIV