Ultrastructural study of plasmodesmata in the brown alga Dictyota dichotoma (Dictyotales, Phaeophyceae)

Abstract

From these results, it is suggested that PPD would be associated with the cell wall development during cytokinesis of D. dichotroma.

Cold-tolerant strain of Haematococcus pluvialis (Haematococcaceae, Chlorophyta) from Blomstrandhalvøya (Svalbard)

“…The chemical fixation and embedding methods were performed as described by Klochkova et al (2006), and the cryofixation and embedding methods were performed as described by Terauchi et al (2012). For high pressure freezing and freeze substitution, a pellet of cells was placed between two copper planchets and rapidly frozen in a high-pressure freezing instrument (EM PACT2; Leica, Solms, Germany) at a pressure of approximately 2,000 atm and at the temperature of liquid nitrogen.…”

Development and function of plasmodesmata in zygotes of Fucus distichus

“…It is also possible that the inner structure of the plasmodesmata differs between thallus and rhizoid, so that the SEL would be affected. In the plasmodesmata of Dictyota dichotoma, internal bridges extending from plasma membrane were observed (Terauchi et al 2012). This structure has not been confirmed in other brown algae, and the function remains obscure.…”

“…These are cytoplasmic canals that pass through the septal cell wall and connect adjacent cells. Plasmodesmata in green plants and brown algae share similar characteristics; however, plasmodesmata in brown algae lack a desmotubule, a tubular strand of connecting endoplasmic reticulum (ER) that penetrates the plasmodesmata of land plants (Terauchi et al 2012). The diameter of the plasmodesmata in land plants is 20-50 nm, but in brown algae, it is 10-20 nm.…”

“…Although plasmodesmata formation in brown algae has been observed in the cytokinesis of vegetative cells, previous studies have shown that the first cytokinesis in zygotes of brown algae is not accompanied by the formation of plasmodesmata. During cytokinesis in the apical meristem of Dictyota dichotoma, plasmodesmata formation is initiated by invaginations of the membranous sacs, transitional membranous structures in the formation of a new cell partition membrane (Terauchi et al 2012), which penetrate the membranous sacs. The region of newly formed plasmodesmata during cytokinesis later becomes a pit field (Terauchi et al 2012).…”

“…During cytokinesis in the apical meristem of Dictyota dichotoma, plasmodesmata formation is initiated by invaginations of the membranous sacs, transitional membranous structures in the formation of a new cell partition membrane (Terauchi et al 2012), which penetrate the membranous sacs. The region of newly formed plasmodesmata during cytokinesis later becomes a pit field (Terauchi et al 2012). Recently, we reported that the complexity of body plan in brown algae influences the number and arrangement of plasmodesmata (Terauchi et al 2015).…”