Comparative ultrastructure of plasmodesmata of Chara and selected bryophytes: towards an elucidation of the evolutionary origin of plant plasmodesmata

Cook, Martha E; Graham, Linda E; Botha, Christiaan E J; Lavin, Colleen A

Title: Comparative ultrastructure of plasmodesmata of Chara and selected bryophytes: towards an elucidation of the evolutionary origin of plant plasmodesmata
Creator: Cook, Martha E
Creator: Graham, Linda E
Creator: Botha, Christiaan E J
Creator: Lavin, Colleen A
Date Issued: 1997
Date: 1997
Type: Article
Identifier: vital:6506
Identifier: http://hdl.handle.net/10962/d1005933
Identifier: http://www.amjbot.org/cgi/reprint/84/9/1169
Description: We have used transmission electron microscopy to examine plasmodesmata of the charophycean green alga Chara zeylanica, and of the putatively early divergent bryophytes Monoclea gottschei (liverwort), Notothylas orbicularis (hornwort), and Sphagnum fimbriatum (moss), in an attempt to learn when seed plant plasmodesmata may have originated. The three bryophytes examined have desmotubules. In addition, Monoclea was found to have branched plasmodesmata, and plasmodesmata of Sphagnum displayed densely staining regions around the neck region, as well as ring-like wall specializations. In Chara, longitudinal sections revealed endoplasmic reticulum (ER) that sometimes appeared to be associated with plasmodesmata, but this was rare, despite abundant ER at the cell periphery. Across all three fixation methods, cross-sectional views showed an internal central structure, which in some cases appeared to be connected to the plasma membrane via spoke-like structures. Plasmodesmata were present even in the incompletely formed reticulum of forming cell plates, from which we conclude that primary plasmodesmata are formed at cytokinesis in Chara zeylanica. Based on these results it appears that plasmodesmata of Chara may be less specialized than those of seed plants, and that complex plasmodesmata probably evolved in the ancestor of land plants before extant lineages of bryophytes diverged.
Format: 10 pages
Format: pdf
Language: English
Relation: Cook, M.E. and Graham, L.E. and Botha, C.E.J. and Lavin, C.A. (1997) Comparative ultrastructure of plasmodesmata of Chara and selected bryophytes: towards an elucidation of the evolutionary origin of plant plasmodesmata. American Journal of Botany, 84 (9). pp. 1169-1178. Available: http://www.amjbot.org/cgi/reprint/84/9/1169

Hits: 590
Visitors: 684
Downloads: 106

Collections

SDG 15. Life On Land

Botha, Christiaan Edward Johannes (Prof)

RU Department of Botany

		Thumbnail	File	Description	Size	Format
View Details Download			SOURCEPDF	PDF	303 KB	Adobe Acrobat PDF	View Details Download