Prechill a mortar and pestle with liquid nitrogen. Place frozen animals dlrectly into liquid nitrogen in the mortar and grind to a powder, adding more liquid nitrogen as necessary in order to prevent thawing. The solution will instantly freeze to a slurry, but this soon thaws in the 65 degree incubation. Incubate the suspension at 65 degrees for 30-60 minutes. It should become reasonably clear.
Phenol extract extensively.
I usually back extract the first interface with 1-2 ml of lysis buffer, and combine the aqueous phase from this with that from the first extraction for all subsequent extractions. There should be very little interface by the last one. Then do a couple of chloroform extractions for good measure. The pellets can be quite difficult to resuspend, and sometimes I resort to short incubations at 65 degrees to speed the process, though this always makes me nervous about lurking RNases. 7. Add LiCl to 2 M and repeat the precipitation.