• Register
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.


Leaving Community

Are you sure you want to leave this community? Leaving the community will revoke any permissions you have been granted in this community.


Fission yeast pak1+ encodes a protein kinase that interacts with Cdc42p and is involved in the control of cell polarity and mating.

A STE20/p65pak homolog was isolated from fission yeast by PCR. The pak1+ gene encodes a 72 kDa protein containing a putative p21-binding domain near its amino-terminus and a serine/threonine kinase domain near its carboxyl-terminus. The Pak1 protein autophosphorylates on serine residues and preferentially binds to activated Cdc42p both in vitro and in vivo. This binding is mediated through the p21 binding domain on Pak1p and the effector domain on Cdc42p. Overexpression of an inactive mutant form of pak1 gives rise to cells with markedly abnormal shape with mislocalized actin staining. Pak1 overexpression does not, however, suppress lethality associated with cdc42-null cells or the morphologic defeat caused by overexpression of mutant cdc42 alleles. Gene disruption of pak1+ establishes that, like cdc42+, pak1+ function is required for cell viability. In budding yeast, pak1+ expression restores mating function to STE20-null cells and, in fission yeast, overexpression of an inactive form of Pak inhibits mating. These results indicate that the Pak1 protein is likely to be an effector for Cdc42p or a related GTPase, and suggest that Pak1p is involved in the maintenance of cell polarity and in mating.

Pubmed ID: 8846783


  • Ottilie S
  • Miller PJ
  • Johnson DI
  • Creasy CL
  • Sells MA
  • Bagrodia S
  • Forsburg SL
  • Chernoff J


The EMBO journal

Publication Data

December 1, 1995

Associated Grants

  • Agency: NCI NIH HHS, Id: CA-09370
  • Agency: NCI NIH HHS, Id: CA14195
  • Agency: NCI NIH HHS, Id: CA58836

Mesh Terms

  • Actins
  • Amino Acid Sequence
  • Base Sequence
  • Cell Cycle Proteins
  • Cell Polarity
  • Cloning, Molecular
  • Fungal Proteins
  • GTP Phosphohydrolases
  • GTP-Binding Proteins
  • Gene Expression Regulation, Fungal
  • Genes, Fungal
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Protein-Serine-Threonine Kinases
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Schizosaccharomyces
  • Sequence Analysis
  • Sequence Homology, Amino Acid
  • cdc42 GTP-Binding Protein, Saccharomyces cerevisiae