Figure 1.

TNF-α promotes nuclear localization of TonEBP without affecting transcript levels. A, TonEBP mRNA levels were unaffected by treatment with TNF-α, IL-1β, or LPS for 4–24 h; as expected, treatment with NaCl (110 mm) resulted in induction. B and C, levels of total cellular TonEBP did not change with TNF-α treatment for 4–24 h. D and E, nuclear and cytoplasmic fraction experiment clearly shows increased nuclear accumulation of TonEBP following TNF-α treatment for 24 h. No discernable depletion of TonEBP in cytoplasmic fraction was seen. Lamin and β-tubulin loading controls showed relatively high purity of fractions. F–I, treatment with IL-1β (F and G) and LPS (H and I) for 4–24 h did not affect the amount of nuclear TonEBP protein. J, immunofluorescent detection of TonEBP in NP cells following 24 h of treatment with NaCl or TNF-α. Inset shows high magnification image of cells. Scale bar, 100 μm. Quantitative measurements represent mean ± S.E. of ≥3 biological replicates. *, p ≤ 0.05; **, p ≤ 0.01. ns, not statistically significant. Neg. CTR, negative control.