JNK1 Deficient Insulin-Producing Cells Are Protected against Interleukin-1β-Induced Apoptosis Associated with Abrogated Myc Expression

Figure 3

Phosphorylated JNK in individual JNK subtype knockdown INS-1 cell lines exposed to IL-1β for 0.5 h. INS-1 cells were transduced with Lentivirus containing shRNA directed against JNK1, JNK2, or JNK3 and nonsense (NS) or empty vector (EV) controls. Cells stably expressing the shRNA plasmids were selected with puromycin. (a) Stable INS-1 cell lines expressing shRNA for JNK1, JNK2, JNK3, nonsense shRNA, or empty vector controls were cultured for 4 days, protein was isolated, and JNK1, JNK2, and JNK3 protein knockdown expression was analyzed by immunoblotting. Data are shown as means ± SEM of independent experiments. Representative blots are shown. (b) Stable INS-1 cell lines expressing shRNA for JNK1, JNK2, JNK3, nonsense shRNA, or empty vector were exposed to 150 pg/mL IL-1β (closed bars) or vehicle (open bars) for 0.5 h. P-JNK was assessed with immunoblotting and normalized to T-JNK. Data were quantified in respect to 46 kDa and 54 kDa P-JNK/T-JNK. Data are shown as means ± SEM of independent experiments. Specific knockdowns of the individual JNK subtypes, JNK1, JNK2, or JNK3, are shown with their respective actin. Blots were cut as indicated by the dotted black line. , , and versus IL-1β exposed NS. Representative gels are shown.

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