The induction of sexual development and virulence in the smut fungus Ustilago maydis depends on Crk1, a novel MAPK protein

MAP kinases (mitogen-activated protein kinases) are activated by dual phosphorylation on specific threonine and specific tyrosine residues that are separated by a single residue, and the TXY activation motif is a hallmark of MAP kinases. In the fungus Ustilago maydis, which causes corn smut disease,...

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Detalles Bibliográficos
Autores: Garrido, Elia, Voß, Ute, Müller, Philipp, Castillo-Lluva, Sonia, Kahmann, Regine, Pérez-Martín, José
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/340296
Acceso en línea:http://hdl.handle.net/10261/340296
Access Level:acceso abierto
Palabra clave:Crk1
Ustilago maydis
MAP kinase
Signal transduction
Fungal virulence
Sexual development
Descripción
Sumario:MAP kinases (mitogen-activated protein kinases) are activated by dual phosphorylation on specific threonine and specific tyrosine residues that are separated by a single residue, and the TXY activation motif is a hallmark of MAP kinases. In the fungus Ustilago maydis, which causes corn smut disease, the Crk1 protein, a kinase previously described to have roles in morphogenesis, carries a TXY motif that aligns with the TXY of MAP kinases. In this work, we demonstrate that Crk1 is activated through a mechanism that requires the phosphorylation of this motif. Our data show that Fuz7, a MAPK kinase involved in mating and pathogenesis in U. maydis, is required to activate Crk1, most likely through phosphorylation of the TXY motif. Consistently, we found that Crk1 is also required for mating and virulence. We investigated the reasons for sterility and avirulence of crk1-deficient cells, and we found that Crk1 is required for transcription of prf1, a central regulator of mating and pathogenicity in U. maydis. Crk1 belongs to a wide conserved protein group, whose members have not been previously defined as MAP kinases, although they carry TXY motifs. On the basis of our data, we propose that all of these proteins constitute a new family of MAP kinases.