Microtubule Sliding within the Bridging Fiber Pushes Kinetochore Fibers Apart to Segregate Chromosomes.
Microtubule Sliding within the Bridging Fiber Pushes Kinetochore Fibers Apart to Segregate Chromosomes.
复制标题
DOI：
10.1016/j.devcel.2017.09.010
复制
发表时间：
2017-10-09
影响因子：
11.8
通讯作者：
Tolić IM
中科院分区：
文献类型：
--
作者：
Vukušić K;Buđa R;Bosilj A;Milas A;Pavin N;Tolić IM
在细胞分裂过程中，有丝分裂纺锤体微管通过对动粒施加力来分离染色体。是什么力量驱动后期染色体分离仍然是一个中心问题。目前人类细胞的后期模型包括着丝粒纤维的缩短和纺锤体极的分离。这两个过程都需要动粒与两极连接。在这里，我们通过结合激光烧蚀、光激活和理论建模，证明着丝粒可以在不附着在一根纺锤杆上的情况下分离。这种分离需要桥接纤维，即连接姐妹动粒纤维的微管束。完整纺锤体中的桥接纤维微管与动粒纤维一起滑动，表明它们之间存在很强的交联。我们得出的结论是，桥接纤维内微管的滑动驱动极分离，并通过这些纤维之间的被动交联的摩擦力将动粒纤维推向极点。因此，桥接纤维内的滑动与着丝粒纤维的缩短一起作用以分离染色体。着丝粒可以在不与一根纺锤体杆有任何连接的情况下分离 着丝粒和纺锤体杆正确分离需要桥接纤维 着丝粒和桥接纤维在后期交联并滑动在一起 桥接纤维中的滑动是人类细胞的后期机制之一 人类细胞有丝分裂中驱动染色体分离的力仍然知之甚少。 Vukušić、Buđa 等人。结合激光烧蚀、光活化和理论，揭示桥接纤维、非动粒微管束在纺锤体极分离中的关键作用。来自动粒和桥接纤维交联的力有助于染色体分离。
During cell division, mitotic spindle microtubules segregate chromosomes by exerting forces on kinetochores. What forces drive chromosome segregation in anaphase remains a central question. The current model for anaphase in human cells includes shortening of kinetochore fibers and separation of spindle poles. Both processes require kinetochores to be linked with the poles. Here we show, by combining laser ablation, photoactivation, and theoretical modeling, that kinetochores can separate without any attachment to one spindle pole. This separation requires the bridging fiber, a microtubule bundle that connects sister kinetochore fibers. Bridging fiber microtubules in intact spindles slide apart with kinetochore fibers, indicating strong crosslinks between them. We conclude that sliding of microtubules within the bridging fibers drives pole separation and pushes kinetochore fibers poleward by the friction of passive crosslinks between these fibers. Thus, sliding within the bridging fiber works together with the shortening of kinetochore fibers to segregate chromosomes. Kinetochores can segregate without any connection to one spindle pole Bridging fibers are required for proper kinetochore and spindle pole separation Kinetochore and bridging fibers are crosslinked and slide together during anaphase Sliding in the bridging fiber is one of the anaphase mechanisms in human cells The forces that drive chromosome segregation in mitosis in human cells remain poorly understood. Vukušić, Buđa et al. combine laser ablation, photoactivation, and theory to uncover a key role for bridging fibers, non-kinetochore microtubule bundles, in spindle pole separation. Forces from kinetochore and bridging fiber crosslinking contribute to chromosome segregation.
登录
查看更多内容
影响因子：
2.8
作者：
Betterton MD;McIntosh JR
通讯作者：
McIntosh JR
影响因子：
4.2
作者：
Asbury CL
通讯作者：
Asbury CL
影响因子：
16
作者：
Jiang, W;Jimenez, G;Fukunaga, R
通讯作者：
Fukunaga, R
影响因子：
7.8
作者：
Cameron, LA;Yang, G;Salmon, ED
通讯作者：
Salmon, ED
影响因子：
--
作者：
HIRAMOTO, Y;NAKANO, Y
通讯作者：
NAKANO, Y