Showing papers by "Steven J. Klosterman published in 2008"
TL;DR: Results suggest that the Basidiomycota have retained the mating and morphogenetic functions of Ste50-type proteins in the N-terminal half of their Ubc2-type adaptors but, additionally, have integrated C-Terminal SH3 domains that are critical for additional signal transduction mechanisms, including those that lead to pathogenesis.
Abstract: Proteins involved in the mitogen-activated protein (MAP) kinase pathway controlling mating, morphogenesis, and pathogenicity have been identified previously in the fungus Ustilago maydis One of these, the Ubc2 adaptor protein, possesses a basidiomycete-specific structure In addition to containing sterile α motif (SAM) and ras association (RA) domains typical of Ste50-like adaptor proteins found in the fungal phylum Ascomycota, Ubc2 also contains two C-terminal SH3 domains Yeast two-hybrid assays indicated that Ubc2 interacts with the MAP kinase-kinase kinase Ubc4 via the SAM domains at each of their respective N-termini Site-directed mutagenesis of ubc2 and complementation analyses revealed that the SAM and RA domains of Ubc2 are essential for filamentous growth These data support a role for the ascomycete-like N-terminus of Ubc2 in regulating pheromone-responsive mating and morphogenesis analogous to the role of Ste50p in Saccharomyces cerevisiae In contrast, C-terminal deletion mutants were fully
28 citations