Related Experiment Video
Updated: Jul 17, 2026

Protein Purification Technique that Allows Detection of Sumoylation and Ubiquitination of Budding Yeast Kinetochore Proteins Ndc10 and Ndc80
Published on: May 3, 2015
Phosphorylation of gamma-tubulin regulates microtubule organization in budding yeast
1Department of Cellular, Molecular, and Developmental Biology, Yale University, New Haven, CT 06520, USA.
Abstract:
gamma-Tubulin is essential for microtubule nucleation in yeast and other organisms; whether this protein is regulated in vivo has not been explored. We show that the budding yeast gamma-tubulin (Tub4p) is phosphorylated in vivo. Hyperphosphorylated Tub4p isoforms are restricted to G1. A conserved tyrosine near the carboxy terminus (Tyr445) is required for phosphorylation in vivo. A point mutation, Tyr445 to Asp, causes cells to arrest prior to anaphase. The frequency of new microtubules appearing in the SPB region and the number of microtubules are increased in tub4-Y445D cells, suggesting this mutation promotes microtubule assembly. These data suggest that modification of gamma-tubulin is important for controlling microtubule number, thereby influencing microtubule organization and function during the yeast cell cycle.
Related Concept Videos
Yeast Signaling
Microtubules
Microtubules have two structurally similar globular protein subunits: α and β tubulins. In the cytosol, the α and β tubulins form a heterodimer. These αβ-heterodimers...
Microtubule Formation
Microtubule Associated Proteins (MAPs)
Destabilization of Microtubules
Microtubule Instability

