Drebrin is phosphorylated by Cdk5-p35 in cultured cells.

<p>GFP-tagged drebrin E (A) or A (B) was transfected with Cdk5-p35 or kinase-negative (kn) Cdk5-p35 in Neuro2A cells. Cells were harvested 24 h after transfection and the cell lysates were subjected to Laemmli’s (upper panels) or Phos-tag SDS-PAGE (lower panels), followed by immunoblotting with anti-GFP antibody. Expression of GFP-drebrin alone is shown in left lane (−). Arrowhead indicates drebrin band shifted upward by coexpression with Cdk5-p35. (C) GFP-drebrin A and p35 were co-expressed in COS-7 cells. At 24 h after transfection, COS-7 cells were stained with anti-myc antibody for p35. Drebrin A was detected by tagged GFP. Cells were also stained with TRITC-phalloidin for actin filaments (not shown). Merge indicates colocalization of drebrin A and p35. Scale bars, 20 μm.