Dynamic properties of intermediate filaments: Disassembly and reassembly during mitosis in baby hamster kidney cells

Abstract

A morphological analysis of the organizational changes in the type III intermediate filament (IF) system in dividing baby hamster kidney (BHK‐21) cells was carried out by immunofluorescence and immunoelectron microscopy. The most dramatic change occurred during prometaphase, when the typical network of long 10‐nm‐diameter IF characteristic of interphase cells disassembled into aggregates containing short 4–6 nm filaments. During anaphase‐telophase, arrays of short IF reappeared throughout the cytoplasm, and, in cytokinesis, the majority of IF were longer and concentrated in a juxtanuclear cap. These results demonstrate that the relatively stable IF cytoskeletal system of interphase cells is partitioned into daughter cells during mitosis by a process of disassembly and reassembly. This latter process occurs in a series of morphologically distinct steps at different stages of the mitotic process.