Effect of Se-methylselenocysteine (MSC) on phospho-Raf, phospho-ERK, phosphorylated p38 mitogen-activated protein kinase (phospho-p38 MAPK) levels in TM6 cells. TM6 cells were synchronized and treated with 50 μM MSC as described in Fig. 1. Equal amounts of TM6 lysates (50 μg of protein) were loaded on each lane. Immunoblots were probed with anti-phospho-Raf, anti-phospho-ERK, anti-phospho-p38 MAPK and anti-actin as described in the Materials and methods section. Levels of the phosphoproteins remained unchanged at 9, 12 and 16 hours but at 24 hours the phosphorylated proteins decreased in MSC-treated cells.