FIGURE 8.

Immunocytochemical characterization of fibroblasts expressing both Tau(295–391) and inducible full-length Tau. The cells possessed normal cytoskeletal morphology both before (A) and after IPTG induction (B), as indicated by the microtubular network labeled for tubulin with mAb YL1/2. Labeling of Tau with mAb 7/51 showed that Tau was only detected after induction (C, without IPTG; D, with IPTG), and the pattern of staining observed was associated with granular structures. By contrast, cells transfected with inducible full-length Tau, in the absence of truncated Tau(295–391), showed normal microtubular networks after induction, whether labeled with mAbs 27/499 (E), 7/51 (F), or YL1/2 (tubulin; G). A higher magnification of a cell in (D) shows the granular staining with mAb 7/51 in the doubly transfected cells following induction of full-length Tau in the absence of microtubule labeling (H). Cells were fixed with 0.3% glutaraldehyde with 0.1% Triton X-100. Scale bars, 20 μm.