title: The Evolution of Cell Division: From Streptophyte Algae to Land Plants.
abstract: The mechanism of cell division has undergone significant alterations during the evolution from aquatic streptophyte algae to land plants. Two new structures evolved, the cytokinetic phragmoplast and the preprophase band (PPB) of microtubules, whereas the ancestral mechanism of cleavage and the centrosomes disappeared. We map cell biological data onto the recently emerged phylogenetic tree of streptophytes. The tree suggests that, after the establishment of the phragmoplast mechanism, several groups independently lost their centrosomes. Surprisingly, the phragmoplast shows reductions in the Zygnematophyceae (the sister to land plants), many of which returned to cleavage. The PPB by contrast evolved stepwise and, most likely, originated in the algae. The phragmoplast/PPB mechanism established in this way served as a basis for the 3D development of land plants.
authors.affiliation: Osnabrück University, Department of Biology and Chemistry, Barbarastrasse 11, 49076 Osnabrück, Germany. Electronic address: henrik.buschmann@biologie.uni-osnabrueck.de.
authors.forename: Henrik
authors.initials: H
authors.lastname: Buschmann
authors.affiliation: Osnabrück University, Department of Biology and Chemistry, Barbarastrasse 11, 49076 Osnabrück, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Zachgo
mesh_terms: D005075:Biological Evolution; D002455:Cell Division / Q000502:physiology; D018385:Centrosome / Q000502:physiology; D010802:Phylogeny; D018521:Plant Physiological Phenomena / Q000235:genetics; D010944:Plants / Q000235:genetics*; D011418:Prophase / Q000502:physiology; D057949:Streptophyta / Q000235:genetics / Q000502:physiology*
keywords: algae; centrosome; evolution; land plant; phragmoplast; preprophase band