Where does HIV integrate into genome and when is it activated?

WARogers RJDuran matilda1 at flash.net
Sun Jul 26 00:09:34 EST 1998


Axel Boldt wrote in message <51685 at sci.med.aids>...
>Hi,
>
>I have two questions about HIV:
>
>1) Is the HIV provirus always integrated at the same spot in the host
>   cell's genome? If yes, where?

Unfortunately, the answer to your question is a negative one.  One of the
primary reasons that the "Vaccination" approach to containing the virus is
not working is because the virus has no particular spot on the RNA and DNA
chain where it goes to.  It is like a microscopic octopus that grabs hold at
anyplace.

>2) What exactly causes the provirus to become active and produce new
>   particles -- is it the activation of the T-cell by antigen?

Someone please correct me if I am wrong, but I do not believe that the virus
actually creates new particles as such.  To the best of my knowledge, the
mature virus is composed of only a single strand of RNA.  It does not have
any DNA, like the nucleus of the T-Cell does.  The nucleus of the T-Cell has
both RNA and DNA.  To answer your question, when the virus enters the T-Cell
with it's single strand of RNA, it does not create new particles to
replicate itself, it simply uses the DNA genes that are already there,
inside the T-Cell.  That's how it puts itself together.

What happens next, if I may be so bold, is that the virus, now having put
itself together with a bunch of new genes, has killed the T-Cell.  The
T-Cell no longer has all of it's genes, because the virus has taken them
away.  Before the T-Cell disintegrates, the virus cuts itself into a whole
bunch of little pieces. That's what's called "Reverse Transcriptase".  When
the T-Cell disintegrates, all those pieces float free into the blood stream.
Those little pieces are new viruses.  Then the viruses go find new T-Cells
to attack, and the cycle starts all over again.
>--
> Axel Boldt  **  axel at uni-paderborn.de  **
math-www.uni-paderborn.de/~axel/




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