Kinetochore-driven formation of kinetochore fibers contributes to spindle assembly during animal mitosis

• Type: Article in International Scientific Journal
• Date: 2004

Authors

Helder Maiato (Author) Other; Rieder, CL (Author) Other; Khodjakov, A (Author) Other

Journal

Title: Journal of Cell Biology

Vol. 167

Pages: 831-840

ISSN: 0021-9525

Publisher: Rockefeller University Press

Indexing

ISI Web of Knowledge - 215 Citations

Scopus - 230 Citations

Other information

Authenticus ID: P-008-PSC

DOI: 10.1083/jcb.200407090

Abstract (EN): It is now clear that a centrosome-independent pathway for mitotic spindle assembly exists even in cells that normally possess centrosomes. The question remains, however, whether this pathway only activates when centrosome activity is compromised, or whether it contributes to spindle morphogenesis during a normal mitosis. Here, we show that many of the kinetochore fibers (K-fibers) in centrosomal Drosophila S2 cells are formed by the kinetochores. Initially, kinetochore-formed K-Fibers are not oriented toward a spindle pole but, as they grow, their minus ends are captured by astral microtubules (MTs) and transported poleward through a dynein-dependent mechanism. This poleward transport results in chromosome bi-orientation and congression. Furthermore, when individual K-fibers are severed by laser microsurgery, they regrow from the kinetochore outward via MT plus-end polymerization at the kinetochore. Thus, even in the presence of centrosomes, the formation of some K-fibers is initiated by the kinetochores. However, centrosomes facilitate the proper orientation of Ill toward spindle poles by integrating them into a common spindle.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10