FIGURE 1.

TC-PTP is a major PTP in UVB-induced STAT3 dephosphorylation in keratinocytes among three PTPs. A, 3PC keratinocytes were cultured and transfected with siRNA specific for TC-PTP, SHP1, or SHP2. Cells were collected after 48 h of siRNA transfection. Total cell lysates were resolved by SDS-PAGE and immunoblotted with antibody specific for phosphorylated STAT3 (PY-STAT3). B, 3PC keratinocytes were cultured and transfected with siRNA specific for TC-PTP. Cells were collected at the indicated time. C, 3PC keratinocytes were cultured and transfected with siRNA specific for TC-PTP, SHP1, or SHP2. Cells were irradiated with UVB at a dose of 80 mJ/cm² and then collected 1 h after irradiation.