Demonstration of the cytoskeleton of lens epithelial cells with gold sol techniques.

1. The Triton-extraction procedure is well suited for the demonstration of the cytoskeleton by TEM. A good preservation of the fine cytoskeletal network depends on optimal drying. 2. Immunogold-labeling is a useful method for visualization of intermediate filaments (IF) and microfilaments (MF). Labelled and unlabelled filaments are discernible. 3. Various methods were tested for a direct gold-labeling of MF with phallotoxin-gold preparations: The application of phalloidin-gold complexes results in an intensive unspecific staining of cytoskeletal filaments. A modified coupling procedure for the binding of phallacidin to transferrin was necessary to avoid the agglomeration of gold particles. The direct labeling of the cytoskeleton by the application of phallacidin-transferrin-gold complexes to Triton-extracted cells demonstrated an enrichment of gold particles on the both types of filaments, but MF and IF were not discernible. The treatment with phallacidin-polylysin-gold complexes demonstrated labelled filaments, but without sufficient intensity.