Title | XMAP215 is a microtubule nucleation factor that functions synergistically with the γ-tubulin ring complex. |
Publication Type | Journal Article |
Year of Publication | 2018 |
Authors | Thawani, A, Kadzik, RS, Petry, S |
Journal | Nat Cell Biol |
Volume | 20 |
Issue | 5 |
Pagination | 575-585 |
Date Published | 2018 May |
ISSN | 1476-4679 |
Keywords | Animals, Microtubule-Associated Proteins, Microtubule-Organizing Center, Microtubules, Multiprotein Complexes, Protein Binding, Protein Interaction Domains and Motifs, Signal Transduction, Time Factors, Tubulin, Xenopus laevis, Xenopus Proteins |
Abstract | <p>How microtubules (MTs) are generated in the cell is a major question in understanding how the cytoskeleton is assembled. For several decades, γ-tubulin has been accepted as the universal MT nucleator of the cell. Although there is evidence that γ-tubulin complexes are not the sole MT nucleators, identification of other nucleation factors has proven difficult. Here, we report that the well-characterized MT polymerase XMAP215 (chTOG/Msps/Stu2p/Alp14/Dis1 homologue) is essential for MT nucleation in Xenopus egg extracts. The concentration of XMAP215 determines the extent of MT nucleation. Even though XMAP215 and the γ-tubulin ring complex (γ-TuRC) possess minimal nucleation activity individually, together, these factors synergistically stimulate MT nucleation in vitro. The amino-terminal TOG domains 1-5 of XMAP215 bind to αβ-tubulin and promote MT polymerization, whereas the conserved carboxy terminus is required for efficient MT nucleation and directly binds to γ-tubulin. In summary, XMAP215 and γ-TuRC together function as the principal nucleation module that generates MTs in cells.</p> |
DOI | 10.1038/s41556-018-0091-6 |
Alternate Journal | Nat Cell Biol |
PubMed ID | 29695792 |
PubMed Central ID | PMC5926803 |
Grant List | DP2 GM123493 / GM / NIGMS NIH HHS / United States F32 GM119195 / GM / NIGMS NIH HHS / United States |