HIV I Flashcards
Is CMV an STI?
yes!
where is HIV 1 and 2 from
HIV 1: Chimpanzee
HIV 2: Sooty Mangabey
how does food handling lead to transmission of HIV
person who is HIV+ handling food with open lesions on hands and no gloves can transmit virus to food which someone will eat
type of virus is HIV
retrovirus - RNA virus
how do retroviruses replicate
they make an RNA dependent DNA polymerase to turn their genome into an intermediate DNA in order to replicate
how can the replication of these RNA retroviruses be inhibited
actinomycin D
the first pathogenic human retrovirus
human T cell leukemia
which of the HIV strands is most common
HIV 1 with subtype B
subfamily of HIV
lentivirinae
what are the characteristics of viruses that fall under subfamily lentivirinae
slow onset of disease, neurological disorders and immunosuppression, D type, cylindrical nucleocapsid core
what are the env genes that are encoded by retrovirus group not lentivirinae
HERV-K (HML-2) and primate evolution syncytins
what do simple retroviruses encode
gag, pol, and env genes (PEG)
what do complex viruses encode
accessory genes such as HIV: tat, rev, nef, vif, vpu
what are the functions of the genes that simple retroviruses encode
gag - group specific antigen (core and capsid proteins)
pol - polymerase (reverse transcriptase, protease, integrase)
env - envelope (glycoproteins)
describe the genome of class VI viruses
retroviruses
RNA, ss, + sense, RT
how many copies of RNA does HIV virus have and describe them
2 copies of +RNA which are non infectious
what generates the ds provirus and what is function of provirus
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
how many orfs and proteins does HIV have
9 orfs and 15 proteins
what allows HIV virus to bind and enter host cell and describe what these things are
gp120 - docking glycoprotein
gp41 - transmembrane glycoprotein
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
CXCR4/ CCR5
big overview of what occurs with HIV replication
binding and fusion, reverse transcriptase, integration, transcription, assembly, budding
what occurs in the budding and fusion and reverse transcription phase of HIV replication
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
what occurs in the integration and transcription phase of HIV replication
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
what occurs in the assembly and budding phase of HIV replication
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
how is HIV transmitted
through infected individual’s blood (needles), semen, or vaginal fluid
how long does HIV survive outside the body
not very long
increased risk of STI infections if one has HIV and increased risk of contracting HIV if one has STI – just know that
thank V-nasty!
where is most of the population living with HIV
sub saharan Africa
where are there low percentages of transmission of HIV in some areas and not others
areas where there are high antiretroviral therapy
