title: Defence sugarcane glycoproteins disorganize microtubules and prevent nuclear polarization and germination of Sporisorium scitamineum teliospores.
abstract: Microtubules (MTs) are involved in the germination of Sporisorium scitamineum teliospores. Resistant varieties of sugar cane plants produce defence glycoproteins that prevent the infection of the plants by the filamentous fungi Sporisorium scitamineum. Here, we show that a fraction of these glycoproteins prevents the correct arrangement of MTs and causes nuclear fragmentation defects. As a result, nuclei cannot correctly migrate through the growing hyphae, causing germinative failure. Arginase activity contained in defence glycoproteins is already described for preventing fungal germination. Now, its enzymatically active form is presented as a link between the defensive capacity of glycoproteins and the MT disorganization in fungal cells. Active arginase is produced in healthy and resistant plants; conversely, it is not detected in the juice from susceptible varieties, which explains why MT depolarization, nuclear disorganization as well as germination of teliospores are not significantly affected by glycoproteins from non-resistant plants. Our results also suggest that susceptible plants try to increase their levels of arginase after detecting the presence of the pathogen. However, this signal comes "too late" and such defensive mechanism fails.
authors.affiliation: Team of Intercellular Communication in Plant Symbiosis, Faculty of Biology, Complutense University. 12 José Antonio Novais Av., 28040 Madrid, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez-Elordi
authors.affiliation: Department of Plant Cell Biology, Institute of Cellular and Molecular Botany (IZMB), University Bonn. 1 Kirschallee St., D-53115 Bonn, Germany.
authors.forename: František
authors.initials: F
authors.lastname: Baluška
authors.affiliation: Team of Intercellular Communication in Plant Symbiosis, Faculty of Biology, Complutense University. 12 José Antonio Novais Av., 28040 Madrid, Spain.
authors.forename: Clara
authors.initials: C
authors.lastname: Echevarría
authors.affiliation: Team of Intercellular Communication in Plant Symbiosis, Faculty of Biology, Complutense University. 12 José Antonio Novais Av., 28040 Madrid, Spain. Electronic address: cvicente@bio.ucm.es.
authors.forename: Carlos
authors.initials: C
authors.lastname: Vicente
authors.affiliation: Team of Intercellular Communication in Plant Symbiosis, Faculty of Biology, Complutense University. 12 José Antonio Novais Av., 28040 Madrid, Spain.
authors.forename: M Estrella
authors.initials: ME
authors.lastname: Legaz
mesh_terms: D001119:Arginase / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism*; D008954:Models, Biological; D008970:Molecular Weight; D015739:Nocodazole / Q000494:pharmacology; D010940:Plant Proteins / Q000378:metabolism*; D031786:Saccharum / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology*; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development*; D014587:Ustilaginales / Q000187:drug effects / Q000502:physiology*
chemical_list: D006023:Glycoproteins; D010940:Plant Proteins; D001119:Arginase; D015739:Nocodazole
keywords: Arginase; Germination; Immunolabeling; Microtubules; Nucleus; Sporisorium scitamineum; Sugar cane