Figure 3

STAT3 cleavage during ES cell differentiation along neural or adipocyte cell lineages. A. Short term differentiation of murine IOUD2 ES cells following removal of LIF for 48 hours. In the adipocyte differentiation protocol, cells were treated with RA between 48 and 72 hours, while cells differentiating along the neural lineage were untreated. Whole cell extracts were immunoblotted with either the anti-STAT3 amino terminal antibody (upper panel, 48 kDa cleaved fragment) or the anti-STAT3 PY705 antibody (lower panel, 43 kDa cleaved fragment). B. 20 day differentiation time course of IOUD2 ES cells along the neural cell lineage. Cells were harvested at the indicated timepoints and whole cell extracts immunoblotted with either the anti-STAT3 amino terminal antibody (upper panel, 48 kDa cleaved fragment) or the anti-STAT3 PY705 antibody (lower panel, 43 kDa cleaved fragment). C. 20 day differentiation time course of IOUD2 ES cells along the adipocyte cell lineage. Cells were harvested at the indicated timepoints and whole cell extracts immunoblotted with either the anti-STAT3 amino terminal antibody (upper panel, 48 kDa cleaved fragment) or the anti-STAT3 PY705 antibody (lower panel, 43 kDa cleaved fragment). Arrows indicate cleaved fragments and the asterisk non-specific bands.