Figure 8

Aberrant neurite growth following inhibition of Hsp27 phosphorylation. Neurons plated on laminin were treated with p38 MAPK inhibitors (SB203580 and SB202190, 10 μM each, added 3 hrs after plating) and fixed 24 hrs later. Representative results are presented. Some neurons showed abortive extension, with neurites wrapping around the cell body, such as the example in panels A-C (arrowheads, A, tubulin, B, Hsp27, C, merged image). In another example, numerous processes were observed, but these terminated in large, flattened and splayed growth cones, as shown in panel D-F (D, tubulin, E, Hsp27, F, merged image). The fibrillar nature of the Hsp27 (E, arrows) and tubulin (D, arrows) is evident and the sites of colocalization with tubulin are also apparent (F, arrows). Also note that there is not a complete overlap of Hsp27 and tubulin at the tips of the growth cones (F, arrowheads). Scale bar – 20 μm.