Fig. 2. Time course of K8 and K18 phosphorylation changes after hyposmotic exposure. HT29 cells were cultured in isosmotic (I) or hyposmotic (H) conditions (37°C) for the indicated time periods. Total cell lysates were prepared by mixing the cells with hot Laemmli sample buffer, followed by SDS-PAGE then immunoblotting using anti-phospho-keratin or anti-total-keratin antibodies as indicated.