Amount of worms to grow for biochemical assays (e.g. fat quantification)

Model Organism: Worms Methods & Reagents
1

Hello:)

I am trying to figure out a close estimate of the number of worms that needs to be grown for fat quantification via triglyceride kit. Usually biochemical studies need so much more worms than RNA-based assays (200 worms are okay).
I read somewhere it is around 10,000 worms for some biochemical assays. (is that too exaggerated?)

Thank you.

2

Hi,

these guys quantified triglyceride content in wildtype and mutant worms using a variety of approaches;

http://www.jlr.org/content/52/6/1281.full

see the figure here for details;

http://www.jlr.org/content/52/6/1281/F7.expansion.html

They got an average figure of ~53ng per wildtype (N2) worm grown at 15 degrees and ~37ng/worm when they were grown at 20 degrees.

I guess from that you can estimate, given that you know the sensitivity of your triglyceride test, how many worms you need?

Hope that helps…

Steve

3

Thank you!That helps a lot! and the links were very useful

In case anyone would try something similar, from another angle, I found another way to do some simple calculations.
worm specific gravity ~1.08 (http://www.wormbook.org/chapters/www_nematodeisolation/nematodeisolation.html)
SG=density/density of water
Density =m/V
Volume of worm depends on its developmental stage and age and can be gotten from (http://www.mcisb.org/people/knight/docs/WormSize.pdf)
ex. early L4 worms=> mass of 1 worm would be (1.08 ug)
for one triacylglyceride kit (as the one provided by Steveh in the link above) forexample, a 25 mg tissue pellet should be used and based on the calculations would need >11,000 worms (~from 4 “100mm” plates)