Left: Analysis of MARCKS expression (red) in HeLa cells by Immunocytochemistry. MARCKS protein was detected with rabbit antibody to MARCKS at 1:1,000 dilution. Cells were co-stained with a mouse anti-beta tubulin antibody (green). Blue: DAPI nuclear stain. The MARCKS antibody recognizes protein localized in the plasma membrane and cytoplasm. Right: Western blot analysis of MARCKS expression (green) in various cell line lysates using rabbit anti-MARCKS antibody (1:1,000).  protein standard,  HEK293,  HeLa,  SH-SY5Y,  COS1,  NIH-3T3,  C6. The blot was probed simultaneously with mouse antibody to GAPDH (M-1376-250, red, 1:5,000). The strong band at 80 kDa corresponds to MARCKS protein, detected only in the proteins of human origin. Slight reactivity is observed in the monkey cells (lane 5), but no reactivity is seen on rodent cells (lanes 6 and 7). The GAPDH antibody used as a loading control reveals a single band at 37 kDa in all preparations.