Flashcards in lecture 20 - HIV & AIDS Deck (31):
people who get HIV but never AIDS. They make antbodies that neutralize nearly all known HIV strains
env reading frame makes...
gp41 and gp120 (joined)
does HIV infect the germ line?
polyprotein? enzyme required?
one long amino acid chain is translated and is then cleaved into multiple, functional proteins using the enzyme PROTEINASE
At what point is HIV invisible to the immune system
once viral cDNA incorporated into nuclear DNA
first observed in?
which cells are targetted? how does HIV stop immune response and win?
eventually HIV particle numbers rise too high and destroy T helper cells and macrophages (CD4) at a rate that production of new cells can't keep up with.
HIV proteinase structure
- 1 amino acid sequence (only 99 amino acids)
- 2 (identical) subunits
symptoms of AIDS
immune system can no longer function without T-helpers and unusual diseases, normally prevented in a healthy person, occur
response after initial infection or nuh?
YES, mild flu symptoms experienced (maybe not noticed) and HIV is neutralised and tagged for destruction by antibodies. VIRAL LOAD DROPS
enzyme for incorporating cDNA into host cell's DNA
3 open reading frames (genes) of HIV...
gag, pol, env - code for polyproteins
diameter of HIV virus?
body fluids - semen, blood, breastmilk
why is HIV considered a lentivirus?
symptoms don't occur until 5-10 years post infection
structure of proteins in HIV critical for?
can infection in babies be prevented?
YES, by drug treatment
gag open reading frame makes...
capsid and matrix
combination AIDS therapy
- AZT inhibitors for reverse transcriptase
- proteinase inhibitor
can you ever be cured?
NO, drugs only delay AIDS
on the outermost of the HIV particle is the _____ _________. Embedded in the membrane are _ ___ proteins and _ ___ proteins are attached to these 'stalks'.. Beneath this layer you find the ______, within which is the ______ which holds _ strands of _____ and the enzyme _______ __________. Tommy's dick is _____ m long.
on the outermost of the HIV particle is the _plasma_ _membrane_. Embedded in the membrane are _3 _gp41_ proteins and _3 _gp120_ proteins are attached to these 'stalks'.. Beneath this layer you find the _matrix_, within which is the _capsid_ which holds _2_ strands of _RNA_ and the enzyme _reverse_ _transcriptase_. Tommy's dick is _3_ m long.
pol reading frame encodes ...
proteinase, reverse transcriptase, and integrase
particle contains RNA genome
when infected cell is activated
DNA from HIV transcribes mRNA then translates the 9 genes and consequently 19 proteins
RNA to cDNA using
how many cases worldwide? where is HIV predominant?
~40 million, ~20 million alone in Africa
cell-mediated response = ?
infected cells eliminated. Tagged to be destroyed because they have virus pieces on MHC molecules (similar to APCs)
length of HIV proteinase
99 amino acids - very simple (more so than lysozyme)
HIV life cylcle
1. HIV's gp120 binds to CD4 antigen receptor protein
2. gd41 allows membranes to fuse and capsid enters T-cell
3. reverse transcriptase makes double stranded DNA from single stranded viral RNA
4. cDNA integrated into nuclear DNA (integrase).
5. sits for years until T-cell is activated
6. virus transcripted and gag, pol, env proteins made
7. bud off into multiple new HIV particles