C. Elegans ageing and cell division

[Wilson WindowWare]

Regarding ageing in C. Elegans discussion:

1. I am unfamiliar with recent work in lifespan extended mutants of C. 
elegans. Were these worms grown on E. coli, and were nutritional factors 
adequately controlled?

2. I did work on axenic cultures of worms with no attempt to work on 
lifespan mutants. My control worms lived some 30 days, maximum, and there 
was a short (<3day) length of time between high survival (95%) and zero 
survival. Do the mutants do better than this? If so, they might truly be 
resisting free radicals, etc. Otherwise, the mutation might involve 
an increased ability of the worms to resist attack by the very bacteria 
they feed on. The crux issue is the question of what is the natural 
maximum lifespan of C. elegans cells. Once this is somehow established, 
then can it be influenced through genetic selection?

3. Part of this work involved a grant application that NIH liked a lot, 
but was buried in a program project that sank under the weight of the 
other grant requests. The gist of the grant involved a combination 
gentic/biochemical/nutritional/ultrastructural approach to aging in C. 
elegans. Old worms show ultrastructural alterations in the form of 
disrupted cell structure and the accumulation of ageing pigments. Because 
you can scan a cross section of a worm at high resolution, and you can 
quantify ageing markers as well as tell exactly their cellular origins, 
you should be able to correlate ageing changes with structure. 
Ultrastructural phenotype selection should be an effective way to get 
mutants because the worms were easily prepared for the scope and the 
cells were so easy to pinpoint.

3a. The biochemical part was important. We had a bulk axenic culture 
method that allowed for the growth of decent masses of worms. I hoped 
that the intracellular pigments, and other, markers could be used as tags 
useful in corellating structure and chemistry. 

So, I guess I'm wondering whether any of these leads have been followed 
up in the 16 years since I did that work?

-- 
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