Just like in our DNA...

[Martijn Faassen]

Tom Loredo <loredo at spacenet.tn.cornell.edu> wrote:
> Martijn Faassen wrote:
>> 
>> The trouble with junk DNA is that it doesn't seem to code for *any* active
>> RNA or protein in the cell. So it's unlikely junk DNA consists of
>> control structures.

> Well, it seems we're all nonexperts who have gone far afield in this
> thread, but I must say I don't follow this line of reasoning at all.
> In fact, as I mentioned already in this thread, there is a lot of
> research in the biophysics community based on the premise that
> the noncoding DNA *is* in fact a control structure---chemicals
> bonding to noncoding regions appear to trigger the expression of adjacent
> coding regions.  The noncoding regions are thus control structures
> that let the environment influence gene expression.

Aaaah..so they're *templates*. That could make sense. Templates are
by a the way somewhat like goto 'labels'. You have to use something like
that in DNA because you don't have numeric addresses.

> The speaker at our colloquium last week spoke of this as if it
> were a broadly accepted viewpoint, but not being in the community
> myself I can't say whether it's highly theoretical or not.

Anyway, this sounds sensible. Though I must add that they can't be
*all* the control structures; the other half must be the coding DNA that
produces the chemicals that bind to this template DNA.

Throwing in a wild theory; this may also explain why there's a lot of 
junk DNA... it can do some simple measurements of how much of a certain
type of chemical is already in the cellular environment. You could have
something like 'if more than 60% of a particular type of template is bound,
express this gene'. You need a lot of duplications for something like
that.

But that's just a wild guess. :)

Regards,

Martijn
-- 
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