Fruiting body development in Coprinus cinereus: regulated expression of two galectins secreted by a non-classical pathway.
Fruiting body formation in the basidiomycete Coprinus cinereus is a developmental process that occurs as a response of the mycelium to external stimuli. First, localized, highly branched hyphal structures (knots) are formed as a reaction to nutritional depletion. Hyphal-knot formation is repressed by light; however, light signals are essential for the development of the hyphal knot into an embryonic fruiting body (primordium) as well as karyogamy, meiosis and fruiting body maturation. The role of the different environmental signals in the initial phases of fruiting body development was analysed. It was observed that two fungal galectins, Cgl1 and Cgl2, are differentially regulated during fruiting body formation. cgl2 expression initiated in early stages of fruiting body development (hyphal knot formation) and was maintained until maturation of the fruiting body, whereas cgl1 was specifically expressed in primordia and mature fruiting bodies. Immunofluorescence and immuno-electron microscopy studies detected galectins within specific fruiting body tissues. They localized in the extracellular matrix and the cell wall but also in membrane-bound bodies in the cytoplasm. Heterologous expression of Cgl2 in Saccharomyces cerevisiae indicated that secretion of this protein occurred independently of the classical secretory pathway.
Boulianne
Robert P
RP
Institut für Mikrobiologie, Eidgenössische Technische Hochschule, Schmelzbergstrasse 7,CH-8092 Zürich, Switzerland1.
Liu
Yi
Y
Institut für Mikrobiologie, Eidgenössische Technische Hochschule, Schmelzbergstrasse 7,CH-8092 Zürich, Switzerland1.
Aebi
Markus
M
Institut für Mikrobiologie, Eidgenössische Technische Hochschule, Schmelzbergstrasse 7,CH-8092 Zürich, Switzerland1.
Lu
Benjamin C
BC
Department of Molecular Biology and Genetics, University of Guelph, Guelph, ON, N1G 2WO Canada2.
Kües
Ursula
U
Institut für Mikrobiologie, Eidgenössische Technische Hochschule, Schmelzbergstrasse 7,CH-8092 Zürich, Switzerland1.
D001483:Base Sequence; D002244:Carbon / Q000378:metabolism; D003302:Coprinus / Q000235:genetics / Q000254:growth & development* / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D037501:Galectin 2; D037161:Galectins; D018507:Gene Expression Regulation, Developmental; D005800:Genes, Fungal; D037102:Lectins / Q000096:biosynthesis* / Q000235:genetics; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics
C103750:CGL1 protein, Coprinus cinereus; C103751:CGL2 protein, Coprinus cinereus; D017931:DNA Primers; D004271:DNA, Fungal; D005656:Fungal Proteins; D037501:Galectin 2; D037161:Galectins; D037102:Lectins; D011994:Recombinant Proteins; D002244:Carbon; D009584:Nitrogen