Figure 5.
Active p35-cdk5 reduces the clustering of PSD-95 and ion channels in COS-7 cells. A, Clustering of PSD-95 and Kv1.4 in COS-7 cells. a–d, COS-7 cells cotransfected with PSD-95 (N-PDZ1–2S), K+ ion channel (Kv1.4) and GFP (a) were immunostained for Kv1.4 (b) and PSD-95 (c). d, Merged b and c. The immunostaining is representative of 72% of transfected cells. e–h, COS-7 cells cotransfected with N-PDZ1–2S, Kv1.4, p35, and cdk5-GFP (e) were immunostained for Kv1.4 (f) and PSD-95 (g). h, Merged f and g. The immunostaining is representative of 96.8% of transfected cells. i–l, COS-7 cells cotransfected with N-PDZ1–2S, Kv1.4, and dominant negative cdk5-GFP (DNcdk5-GFP, inactive kinase, i) were immunostained for Kv1.4 (j) and PSD-95 (k). l, Merged j and k. The immunostaining is representative of 68% of transfected cells. Immunofluorescence images were taken by Delta Vision microscopy. Scale bars, 10 μm. B, Clustering of the T19A, S25A, S35A truncated PSD-95 mutant and Kv1.4 in COS-7 cells. a–c, COS-7 cells cotransfected with the T19A, S25A, T19A mutant PSD-95 (N-PDZ1–2S), Kv1.4, p35, and cdk5-GFP (a) were immunostained for Kv1.4 (b) and PSD-95 (c). d–f, COS-7 cells cotransfected with the T19A, S25A, S35A mutant N-PDZ1–2S, Kv1.4, and GFP (d) were immunostained for Kv1.4 (e) and PSD-95 (f). Immunofluorescence images were taken by Delta Vision microscopy. Scale bars, 10 μm.