Send to

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2002 Jul 26;277(30):26721-4. Epub 2002 Jun 10.

Localization of the Rsr1/Bud1 GTPase involved in selection of a proper growth site in yeast.

Author information

  • 1Graduate Program in Molecular, Cellular, and Developmental Biology, Department of Molecular Genetics, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210-1292, USA.


Yeast cells organize their actin cytoskeleton in a highly polarized manner during vegetative growth. The Ras-like GTPase Rsr1/Bud1 and its regulators are required for selection of a specific site for growth. Here we showed that Rsr1/Bud1 was broadly distributed on the plasma membrane and highly concentrated at the incipient bud site and polarized growth sites. We also showed that localization of Cdc24, a guanine nucleotide exchange factor for the Cdc42 GTPase, to the proper bud site was dependent on Rsr1/Bud1. Surprisingly, Rsr1/Bud1 also localized to intracellular membranes. A mutation in the lysine repeat in the hypervariable region of Rsr1/Bud1 specifically abolished its plasma membrane localization, whereas a mutation at the CAAX motif eliminated both plasma membrane and internal membrane association of Rsr1/Bud1. Thus the lysine repeat and the CAAX motif of Rsr1/Bud1 are important for its localization to the plasma membrane and to the polarized growth sites. This localization of Rsr1/Bud1 is essential for its function in proper bud site selection because both mutations resulted in random bud site selection.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center