Abstract
γ-Tubulin is central to the nucleation of microtubule assembly in vivo. Although it is most obviously located at microtubule organizing centers, it is also found in soluble cytoplasmic complexes. Characterizing these complexes and identifying proteins that interact with γ-tubulin in vivo will be necessary if γ-tubulin function is to be understood fully. We have begun to investigate soluble complexes of γ-tubulin in Aspergillus nidulans, the organism in which γ-tubulin was discovered and in which a great deal of genetic and molecular genetic analysis of γ-tubulin has been carried out. We find that approximately 32% of the γ-tubulin in A. nidulans is soluble. Sucrose density gradients revealed that the soluble γ-tubulin is in 8-20S complexes with little or no monomeric γ-tubulin present. In the presence of 0.5 M KCl, the average size of the complexes decreased and a peak was present between 4S and 11S. Cross-linking experiments with a zero-length cross- linker suggest that γ-tubulin in isolated nuclei and in intact hyphae interacts physically with three proteins with molecular weights of approximately 105, 95, and 80 kDa.
Original language | English (US) |
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Pages (from-to) | 149-158 |
Number of pages | 10 |
Journal | Cell Motility and the Cytoskeleton |
Volume | 37 |
Issue number | 2 |
DOIs | |
State | Published - 1997 |
Externally published | Yes |
Keywords
- Microtubule organizing centers
- Microtubules
- Spindle pole bodies
ASJC Scopus subject areas
- Structural Biology
- Cell Biology