[Dioxin-l] molecular mechanism of dioxin action

[david bell]

Hi Tony
one of the things that made dioxin so interesting scientifically, is because 
it shattered several paradigms about how chemicals cause cancer. Before 
dioxin, the view was that chemicals simply reacted with DNA, caused 
mutations and hence cancer. Dioxin was one of the first cancer causing 
chemicals which was demonstrated not to bind (or react with, stay associated 
with) to DNA. So dioxin isn't associated with DNA except when it is bound to 
AhR (Alan Poland did this stuff, I believe).

It isn't clear that there isn't some residual AhR with dioxin bound, which 
remains in the nucleus activating transcription. It is difficult to do the 
experiments well enough to exclude this possibility.

cheers
david

>From: Tony Tweedale <ttweed@wildrockies.org>
<snip>
>david or anyone:  why would this be the case--can't TCDD alone (or TCDD
>complexed w/ anything else but sans AHR), stay glommed onto chromosones?
>What does the literature say, if anything (or did I miss something
>pertinent that ws already posted)?

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