Abstract

Fluorescein isothiocyanate (FITC) conjugated phalloidin was used to label F-actin in Aglaothamnion oosumiense Itono, and Griffithsia japonica Okamura. Labelling was achieved without treatment by wall-digesting enzymes. Formaldehyde fixation followed by Triton X-100 wash gave good preservation of F-actin and cell components. Extensive arrays of F-actin were observed in the peripheral cytoplasm and nuclear area of the two species. Actin was strongly associated with the pit plugs in both species. Quantitative analysis using confocal microscopy showed that the amount of F-actin increased during cell division in Aglaothamnion oosumiense. Actin also appeared to play an important role in cytokinesis and karyokinesis during tetrasporogenesis.