Fine structural demonstration of ordered arrays of cytoplasmic filaments in vertebrate iridophores: A comparative survey

Abstract

Thin and thick sections of both physiologically active and physiologically passive iridophores from a range of vertebrate species have been examined by electron microscopy at 60 kV and at 1,000 kV. All iridophores studied have been found to contain 65-Å filaments linking successive crystals in their parallel stacks ; their orientation in the cell is shown in stereo pairs of 0.25-µm sections obtained from high voltage microscopy. In addition, several of the physiologically passive iridophores contain 100-Å filaments in varying numbers. It is suggested that the thin filaments might be iridophore actin and play a role in the movement of iridophore components, and that the 100-Å filaments might play a cytoskeletal role in the iridophores in which they occur. © 1974, Rockefeller University Press., All rights reserved.