Regulated offloading of cytoplasmic dynein from microtubule plus ends to the cortex

Dev Cell. 2011 May 17;20(5):639-51. doi: 10.1016/j.devcel.2011.04.011.

Abstract

Cytoplasmic dynein mediates spindle orientation from the cell cortex through interactions with astral microtubules, but neither the mechanism governing its cortical targeting nor the regulation thereof is well understood. Here we show that yeast dynein offloads from microtubule plus ends to the daughter cell cortex. Mutants with an engineered peptide inserted between the tail domain and the motor head retain wild-type motor activity but exhibit enhanced offloading and cortical targeting. Conversely, shortening the "neck" sequence between the tail and motor domains precludes offloading from the microtubule plus ends. Furthermore, chimeric mutants with mammalian dynein "neck" sequences rescue targeting and function. These findings provide direct support for an active microtubule-mediated delivery process that appears to be regulated by a conserved masking/unmasking mechanism.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Cytoplasmic Dyneins / metabolism*
  • Cytoskeletal Proteins / metabolism*
  • Microtubules / metabolism*
  • Mutation
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Cytoskeletal Proteins
  • NUM1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Cytoplasmic Dyneins