Worm lysis can be performed on a single worm or a pool of worms. For a pool, 50-60 worms should be enough.
Worm Lysis Solution (10ml):
500ul 1M KCl
100ul 1M Tris pH8.3
25ul 1M MgCl2
45ul Tween 20
50ul 2% gelatin
ddH2O to 10ml
Each time a worm lysis is done, take a 950ul aliquot of the worm lysis solution and add 50ul Proteinase K (stock solution at 20mg/ml).
In a 0.5ml tube, use 50-60 ul for a pool of 50-60 worms. Use up to 30 or 40ul for a single worm.
Freeze the tube at -80°C. This is a freeze-crack step, which will help liberate the DNA.
Incubate the tube at 60°C for 60 minutes, followed by a 95°C incubation for 15 minutes. Cool to 4°C by placing on ice. Alternatively, this whole cycle is on the MJ PTC-100 thermocycler in a program called "60-95-4."
The lysed worm solution is now ready to use for PCR, or other applications.
For a larger, cleaner genomic DNA stock, see the "Genomic DNA Prep" protocol.