title: CHARACTERIZATION OF A RABE (RAS GENE FROM RAT BRAIN E) GTPASE EXPRESSED DURING MORPHOGENESIS IN THE UNICELLULAR GREEN ALGA MICRASTERIAS DENTICULATA (ZYGNEMATOPHYCEAE, STREPTOPHYTA)(1).
abstract: Rab GTPases are central regulators of cell shape in land plants by coordinating vesicle trafficking during morphogenesis. To date, relatively little is known about the role of these ubiquitous signaling proteins during cell growth in microalgae, in particular in the related charophyte algae. This article identifies the first charophyte Rab GTPase, MdRABE1, in Micrasterias denticulata Bréb., a convenient model organism for studying morphogenesis. Its expression correlated with the onset of morphogenesis, and structural analysis indicated that it belongs to the RABE (Ras gene from rat brain E) subclass. Confocal fluorescence and immunoelectron microscopy (IEM) of transiently GFP-MdRABE1 overexpressing interphase cells demonstrated that the GFP-MdRABE1 protein was localized to the endoplasmic reticulum, dictyosomes, exocytotic vesicles, the cell margin, the membranes of cell organelles, and in the isthmus zone around the nucleus. Although overexpression phenotyping of both N- and C-terminal green fluorescent protein (GFP) fusions failed to indicate additional functional evidence of the MdRABE1 protein due to mortality of those transgenic cells, its expression profile, bioinformatics, and intracellular localization suggest a role in vesicle trafficking during morphogenesis.
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: Katrijn
authors.initials: K
authors.lastname: Vannerum
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: Riet
authors.initials: R
authors.lastname: De Rycke
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: Jacob
authors.initials: J
authors.lastname: Pollier
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: Alain
authors.initials: A
authors.lastname: Goossens
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Inzé
authors.affiliation: Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, 9000 Gent, BelgiumDepartment of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, BelgiumDepartment of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052 Gent, Belgium.
authors.forename: And Wim
authors.initials: AW
authors.lastname: Vyverman
keywords: Micrasterias denticulata; Rab GTPase; gene expression; green algae; localization; morphogenesis; overexpression