Fig. 6

F-actin is detectable in GBM cell cilia. L0 Arl13b:GFP⁺ clones (a), parental L0 cells (b), L0 xenograft-derived tumors (c), and a patient biopsy (d) were immunostained for different cilia markers and Alexa Fluor 488-conjugated phalloidin that labels F-actin. Scattered primary cilia in which F-actin (arrowheads) colocalized with cilia markers in two examples of clone D4, parental L0 cells, L0 xenografts, and a patient biopsy are shown. Patient biopsies were stained for aaTub (red), F-actin (green), and pericentriolar material 1 (PCM1; blue), a protein that localizes to centriolar satellites around the ciliary base, with nuclei stained for DAPI (purple). Examples of F-actin-negative cilia are shown in the xenografts and biopsy. Scale bar in a, d = 5 μm