Fig. 4.
The soluble PC1 tail causes hypersensitivity to cytokine signaling. (A) Cell cycle analysis by flow cytometry. Stably-transfetcted FLS-PC1 MDCK cells were induced for 48 h with DOX in conjunction with the indicated cytokines. (Left) Actively cycling cells (S/G2M phase). (Right) Hypodiploid cells. Data are normalized to control (untreated) cells and represented as mean-fold difference ± SE from three independent experiments. (B) Western blots of kidney lysates. Twenty-one-day-old wild-type or bpk cystic animals were treated for 2 (low dose) or 5 (high dose) d with either vehicle, low dose (+, 1.2 μg), or high dose (++, 3 μg) IFNγ as indicated. PY-STAT3 is elevated in cystic animals, independent of treatment. IFNγ-treated cystic animals exhibit increased caspase-3 activation, indicative of apoptosis.