JNK1 and/or JNK2 are preferentially phosphorylated during mitosis of progenitor cells in developing retina.

<p>(A, B) Representative confocal photomicrographs of immunohistochemistry for phospho-JNK1/2 (red) and phospho-histone-H3 (green) in sections of retinal tissue maintained for 3 hours <i>in vitro</i> either in absence (A - CTR) or presence of taxol (B - TAX). The sections were counterstained with DAPI (blue). Cells double stained for phospho-JNK1/2 and phospho-histone-H3 are indicated with arrows. Scale bar: 20 µm. Inset: higher magnification of mitotic cells. (C) Representative western blot of phosphorylated JNK in total protein extracts of retinal explants maintained for 3 hours <i>in vitro</i> either in absence (CTR) or presence of taxol (TAX). The upper blot was done with the antibody for phospho-JNK, the middle blot with an antibody for phospho-histone-H3, and the lower blot with an antibody for β-actin as loading control. (D) Densitometric analysis of the western blot of phospho-JNK. Data are means±S.E.M. from three independent experiments. CTR - control; TAX - taxol; GCL - ganglion cell layer; NBL - neuroblastic layer. * <i>P</i><0.05 versus CTR.