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Title: Mps1 promotes poleward chromosome movements in meiotic prometaphase
In prophase of meiosis I, homologous chromosomes pair and become connected by cross-overs. Chiasmata, the connections formed by cross-overs, enable the chromosome pair, called a bivalent, to attach as a single unit to the spindle. When the meiotic spindle forms in prometaphase, most bivalents are associated with one spindle pole and then go through a series of oscillations on the spindle, attaching to and detaching from microtubules until the partners of the bivalent become bioriented—attached to microtubules from opposite sides of the spindle. The conserved kinase, Mps1, is essential for the bivalents to be pulled by microtubules across the spindle in prometaphase. Here we show that MPS1 is needed for efficient triggering of the migration of microtubule-attached kinetochores toward the poles and promotes microtubule depolymerization. Our data support the model Mps1 acts at the kinetochore to coordinate the successful attachment of a microtubule and the triggering of microtubule depolymerization to then move the chromosome.  more » « less
Award ID(s):
2029286
PAR ID:
10274708
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Bloom, Kerry
Date Published:
Journal Name:
Molecular Biology of the Cell
Volume:
32
Issue:
10
ISSN:
1059-1524
Page Range / eLocation ID:
1020 to 1032
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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