Reorganization of the Cytoskeleton by Interferon in MSV-Transformed Cells*

beta and gamma interferons were found to enhance the organization of microfilaments, intermediate filaments, and fibronectin in the murine sarcoma virus (MSV)-transformed cell line. Furthermore, both interferons increased the number of intermediate-type junctions. Sodium butyrate was also found to act in a similar way and, when associated with interferon, an additive effect was observed. In the cell line, cultured for many passages in the presence of beta interferon (MSV-IF+), the cytoskeletal network and the extra-cellular matrix were highly developed and were reminiscent of a normal cell. These results could explain some of the biological actions of interferon, such as increased cell adhesion to the substratum and decreased cell motility.