Preparing extracts from cultured cells

  • Suspend cells by pipetting up and down (Drosophila cells) or scraping off (mammalian cells).
  • Harvest the cells by centrifuging at 2000 rpm for 2 min.
  • Discard the medium and suspend the cells in 80 ul extraction buffer.
  • Lyse the cells by pipetting up and down.
  • Add 20 ul 5x Laemmli solution. Incubate at 100¡C for 5 min.
  • Analyse an equivalent of 10 cells per lane by SDS-PAGE.
Extraction buffer: for example the IP buffer
50 mM Hepes/NaOH pH 7.5, 150 mM NaCl, 1% TritonX100, 10% glycerol, 1.5 mM MgCl2, 1 mM EGTA.