Western blot analysis of the protein ENS-1.

<p>(<b>A</b>) Proteins (15 μg) of whole cell lysates from murine (MES) and chicken (CES) cells were analyzed by western blot using the anti-ENS-1 3807 antibody. Protein loading was equivalent in both conditions as illustrated by the Ponceau's red staining of the blot. (<b>B</b>) Proteins lysates (20 μg) from CES cells transfected with an HA-tagged ENS-1 protein (lanes 4,5,6) or with an empty vector (lanes 1,2,3) were compared with untransfected cells (WT, lane 7). Triplicates were from three independent transfection experiments. The HA-tagged protein was detected by the 3807 antibody and by the anti-HA antibody at a molecular weight of 60 kDa. The anti-ENS1 antibody also detected the endogenous protein at 55 kDa. Both proteins differed in size by 3 kDa corresponding to the 33 additional amino acids added at the C-terminal part of ENS-1 in the transgenic protein in addition to the two HA tags (2.4 kDa). (<b>C</b>) Western blot analysis of ENS-1 and HP1γ (Chemicon antibody) in whole cell lysates (12 μg) from undifferentiated CES (-RA) or CES induced to differentiate with retinoic acid (RA, 10⁻⁶M) for 4 to 48 h as indicated. HSP90 was used as protein loading control.