Sign up for labeling area - check with other people who may be labeling to avoid too many people doing complicated labelings at same time. 300 uCi is also fine. Do 3 cycles of freezing and thawing to extract membrane proteins. 20 mM 2-mercaptoethanol. Boil again to thaw - do not allow to thaw slowly.
Lyophilize cell extract over night.
Freeze on dry ice and lyophilize a second time. Then ready to add antibody. No reason to do TCAs. Centrifuge 2 min and discard supernatant into appropriate liquid hot waste bottle. Add 0.5 ml TCA solubilizer solution and heat 5 min at 100 o C. Check that pellet has dissolved, allow to cool and then transfer to scintillation vial and get 1 min counts.