Figure 5. Blocking Cdk5 activity with roscovitine inhibited p35 and Cdk5 clustering with actin fibres and talin-integrin beta-1 complex.

Inhibition of Cdk5 activity with roscovitine hampered co-localization of pCdk5 (panel A) and p35 (panel B) with actin filaments and stress fibres, resulting in production of abnormal cytoplasmic bundles with actin (arrows in magnification) in early spreading. (C) Roscovitine impaired the formation of talin tips and their co-localization with p35 and integrin beta-1. (D) Western blot showing increased talin fragmentation (47kDa domain), in roscovitine treated cells.

Calculated results are reported in graphs: E, level of talin protein fragmentation in untreated cells and with roscovitine treatment; F, protein level of talin large domain (235kDa) in untreated and roscovitine treated cells. Data are expressed as mean ±SD of biological triplicates. * P <0.05. P value calculated using the Student t test. Immunofluorescence confocal analysis, objective 65x. Bars, 25 µm. Original magnification, x 200. Original magnification in merge Bii, x 230. Each experiment was performed in triplicate.