Excelife wrote:
> Jeff Dee wrote:
> >I've been wondering... is the introduction of
> >hTERT into a cell a one-time operation, or does
> >it eventually "wear out" and have to be re-
> >introduced?
>> An excellent question Jeff and one that deserves exploring. I don't think
> the published research specifically addressed that question but the fact that
> the cells continued to live beyond their normal senescence would suggest that
> hTERT, a sub-unit of the enzyme telomerase, remained active.
>> An alternative explanation would be that the "telomerase" was only active for
> sufficient time to add additional telomeres to the chromosomes ,enabling the
> cells to live beyond senescence, and then became inert.
Please excuse my undoubtedly inept questions -
I'm not a biologist or any other kind of
scientist, I'm just a layman who tries to keep
himself reasonably informed.
What I've heard (albeit second-hand) is that some
of these treated cells have *more than* doubled
their normal number of replications. So either
the telomerase has remained active the whole time,
or else the cells must have been given extra-long
telomeres? Or is there some other explanation?
> You have, apparently intentionally, hit on one of the keys to the problem.
> If the first case is true then the cell line would be "immortal" and would
> exhibit the uncontrolled growth we normally associate with cancer.
>> In the latter case you would have a finite growth of the cell line which
> could continue functioning normally. There would be additional cellular mass
> based on the number of additional reproductions the cell line experienced but
> these cells would eventually lose their telemeric length, enter senescence
> and in due course die. It would just take a little bit longer!
So, does the mere presence of telomerase trigger
cell division? My understanding was that certain
cells in the human body contain telomerase
naturally, without going cancerous.
> If extending the life of somatic cells can translate into extended life for
> the entire organism....
I'm sure we're all keeping our fingers crossed on
that...
-Jeff Dee
--
"It is as morally bad not to care whether a thing is true
or not, so long as it makes you feel good, as it is not to
care how you got your money as long as you have got it."
-Edmund Way Teale, "Circle of the Seasons", 1950
jeff at illusionmachines.com *
illusionmachines.com/personal/jeff/index.html
