Intermediate filament formation by a yeast protein essential for organelle inheritance.
Intermediate filaments are abundant cytoskeletal components whose specific cellular functions are poorly understood. The Saccharomyces cerevisiae protein MDM1 displays structure and solubility properties that are similar to those of intermediate filament proteins of animal cells. Yeast cells that have a mutant form of MDM1 exhibit temperature-sensitive growth and defective transfer of nuclei and mitochondria to daughter cells during incubation at the nonpermissive temperature of 37 degrees C. The purified, wild-type MDM1 protein readily forms 10-nanometer-wide filaments at either 4 degrees C or 37 degrees C. In contrast, the purified, mutant protein forms filaments at 4 degrees C but fails to form such structures at 37 degrees C. These results suggest that intermediate filament proteins are universal components of eukaryotic cells.
McConnell
S J
SJ
Department of Biology, University of California, San Diego, La Jolla 92093.
Yaffe
M P
MP
D018797:Cell Cycle Proteins; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005800:Genes, Fungal; D007381:Intermediate Filament Proteins; D007382:Intermediate Filaments / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008928:Mitochondria / Q000378:metabolism; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D029701:Saccharomyces cerevisiae Proteins; D013696:Temperature
D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D007381:Intermediate Filament Proteins; C075618:MDM1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins