Help on HIV proteins - vif, vpr, vpu

[Mike Poidinger]

ak961 at freenet.HSC.Colorado.EDU (Prateek K. Lala) wrote:


>In a previous article, p_travers at icrf.icnet.uk (Paul J Travers) says:

>>Can anyone tell me what the HIV proteins vif, vpr and vpu actually do?  Or
>>point me at the relevant literature.  I really need a relatively simple
>>explanation - it's for a textbook for medical students :-)

>In very basic terms, the proteins mentioned above are thought to perform
>the following functions:

>_Gene_    _Protein_                 _Putative functions_

> vif        p23        Virion Infectivity Factor: promotes infectivity of
>                          cell-free virions.
> vpr        p15        Viral Protein R: weakly activates transcription
> vpu        p16        Viral Protein U: required for efficient viral
>                          assembly and budding from host cells; in HIV-2,
>                          vpx is an analogous protein.

>These are functions that have been experimentally observed, and probably
>do not cover the entire extent of their true functions.

Just attended a seminar Ahmed Azad, concerning the functions of Nef and vpr.
Here are some fragmented memories...

vpr is highly toxic in yeast and mammalian cells, and causes arrest of cell
growth cycle.  In yeast it causes yeast cells to be 8 times their normal size,
lysis, and general inhibition of colony formation.  It has its effect at the
plasma membrane and can be countered by co transfection with TMB8 (?) a calcium
ion channel.


Mike

------------------------------------------------------------------------------
Dr Mike Poidinger      Now don't be lazy, 
Microbiology, UQ       with the pleasure of sin  (Nitzer Ebb)
Australia              
mikep at biosci.uq.oz.au  
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