Fig. 7. Neuronal kinase cdk5 can modulate the affinity of MIR1 for microtubules. BHK cells were transfected with cdk5, its activator p35 and GFP-MIR1. Controls were performed with an inactive version of cdk5 (cdk5DN) and with GFP-MIR1A instead of the wild-type MIR1 fusion. Samples were processed for immunofluorescence microscopy 12 hours after transfection. The cells were analyzed for GFP fluorescence and for staining of microtubules. The arrow points to a cell expressing active cdk5 that shows diffuse MIR1 staining. The arrowheads point to cells expressing either inactive cdk5 or a non-phosphorylatable form of MIR1; these cells show colocalization of MIR1 and microtubules.