Isolation and Characterization of Effector-Loop Mutants of CDC42 in Yeast

AUTOR(ES)

Gladfelter, Amy S.

FONTE

The American Society for Cell Biology

RESUMO

The highly conserved small GTPase Cdc42p is a key regulator of cell polarity and cytoskeletal organization in eukaryotic cells. Multiple effectors of Cdc42p have been identified, although it is unclear how their activities are coordinated to produce particular cell behaviors. One strategy used to address the contributions made by different effector pathways downstream of small GTPases has been the use of “effector-loop” mutants of the GTPase that selectively impair only a subset of effector pathways. We now report the generation and preliminary characterization of a set of effector-loop mutants of Saccharomyces cerevisiae CDC42. These mutants define genetically separable pathways influencing actin or septin organization. We have characterized the phenotypic defects of these mutants and the binding defects of the encoded proteins to known yeast Cdc42p effectors in vitro. The results suggest that these effectors cannot account for the observed phenotypes, and therefore that unknown effectors exist that affect both actin and septin organization. The availability of partial function alleles of CDC42 in a genetically tractable system serves as a useful starting point for genetic approaches to identify such novel effectors.

Documentos Relacionados

• Myotonic Dystrophy Kinase-Related Cdc42-Binding Kinase Acts as a Cdc42 Effector in Promoting Cytoskeletal Reorganization
• Gastric Hyperplasia in Mice Lacking the Putative Cdc42 Effector IQGAP1
• MSE55, a Cdc42 effector protein, induces long cellular extensions in fibroblasts
• Genghis Khan (Gek) as a putative effector for Drosophila Cdc42 and regulator of actin polymerization
• Involvement of IQGAP1, an Effector of Rac1 and Cdc42 GTPases, in Cell-Cell Dissociation during Cell Scattering