Figure 5.

Intracellular distribution of vimentin peptides and control substances after microinjection into SW 13 [vimentin⁻] cells. F-cys₁-NT1 is found in both the cytoplasm and nucleus (A, fluorescein channel). T-vimentin (B, composite panel of both fluorescein channel [green] and propidium iodide channel [red]), visualized with an anti-vimentin antibody and an FITC-labeled second antibody, remains in the cytoplasm (fluorescein channel) and has no effect on nuclear structure or chromatin distribution (propidium iodide channel). FITC-dextrans of molecular weight 20–70,000 or higher remained in the cytoplasm and had no effect on nuclear architecture (C, composite of both fluorescein channel [green] and propidium iodide channel [red] after microinjection of MW 70,000 FITC-dextran). Smaller dextrans (i.e., MW 4000 FITC-dextran) were distributed throughout the cell, i.e., readily entered the nucleus, but had no effect on nuclear architecture (our unpublished results). Bar, 10 μm (A–C).