gamma-tubulin complexes: binding to the centrosome, regulation and microtubule nucleation

Curr Opin Cell Biol. 2000 Feb;12(1):113-8. doi: 10.1016/s0955-0674(99)00064-2.


Microtubule assembly is initiated in vivo by gamma-tubulin complexes. Cytoplasmic gamma-tubulin complexes are targeted to centrosomes or to other microtubule organizing centers (MTOCs) via a set of so called gamma-tubulin complex binding proteins (GTBPs) that probably interact with the conserved Spc97p/Spc98p protein family of gamma-tubulin complexes. In other cell types, gamma-tubulin complexes may initiate microtubule formation near chromosomes in a MTOC-independent manner. Recently, major advances have been achieved through the finding that gamma-tubulin, Spc97p and Spc98p form a conserved core that is probably responsible for microtubule nucleation, and by the discovery that a yeast GTBP is regulated in a cell-cycle-dependent manner and in response to an external signal. Furthermore, it was found that the small GTPase Ran in its GDP-bound state may promote spindle assembly. In addition, an essential function of gamma-tubulin in basal body duplication has been demonstrated in Paramecium.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Centrioles / metabolism
  • Centrosome / metabolism*
  • Humans
  • Microtubules / metabolism*
  • Protein Binding
  • Spindle Apparatus / metabolism
  • Tubulin / chemistry
  • Tubulin / metabolism*
  • ran GTP-Binding Protein / metabolism


  • Tubulin
  • ran GTP-Binding Protein