Polygonal arrays of actin filaments in human lens epithelial cells. An aging study.

In order to determine the importance of lens actin filament configuration to lens accommodation, the pattern of actin filaments in the epithelium was studied in human lenses from different decades of life spanning the accommodative and non-accommodative years. Polygonal arrays of microfilaments were demonstrated in whole mounts of epithelium from normal and cataractous lenses using rhodamine phalloidin, an actin-specific, fluorescent-labeled probe. Tangential section transmission electron microscopy (TEM) studies confirmed that these arrays consist of central vertices and interconnecting filament rays, which line the apical end of each epithelial cell and appear to attach to the lateral membrane. These polygonal arrays were present in human lenses ranging from 25-94 yr of age. Measurements of intervertex distance showed remarkable constancy throughout the ages studied. In view of these findings, it is proposed that a possible function of these polygonal arrays is to stabilize the lens epithelium during lens flattening.