Alisma plantago-aquatica L.: the cytoskeleton of the suspensor development

Abstract

The actin and the tubulin cytoskeleton organization during the differentiation of the embryo-suspensor in <em>Alisma plantago-aquatica</em> was studied in comparison with the development of embryo, using immunofluorescence detection and rhodamine-phalloidin assay. At the early stage of the suspensor basal cell development (from 2- to ~10-celled embryos) microfilaments form an abundant network in the cytoplasm of the basal cell, while the microtubules form a delicate network. At the mature stage of development (from a dozen to several dozen-celled embryos), in the suspensor basal cell, the microfilaments and microtubules were localized from micropylar to chalazal pole of the cell. At the micropylar end of the basal cell a high amount of actin and tubulin material was observed. The microfilaments were mainly arranged parallel whereas numerous bundles of microtubules distributed longitudinally or transversally to the long axis of the cell. At this stage of basal cell functioning, some bundles of microtubules appeared to pass close to the nucleus surface. Microtubules were also observed distributed at the chalazal pole of the basal cell. At the senescence stage of the suspensor basal cell (&gt;100-celled embryos) the actin and tubulin filaments disorganize, some disrupted microfilaments and microtubules were observed in the cytoplasm of the basal cell. At all stages of the suspensor basal cell development in the embryo cells an extensive actin and tubulin network was observed.