Naslov
Microtubule sliding in the bridging fiber pushes kinetochore fibers apart to segregate chromosomes

Autori
Buđa, Renata ; Vukušić, Kruno ; Bosilj, Agneza ; Milas, Ana ; Pavin, Nenad ; Tolić, Iva M.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, znanstveni

Skup
Dynamic kinetochore EMBO Workshop

Mjesto i datum
Edinburgh, Ujedinjeno Kraljevstvo, 06.06.2017. - 09.06.2017

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
cell division ; anaphase ; bridging fiber ; human cells

Sažetak
During cell division, microtubules of the mitotic spindle segregate chromosomes by exerting forces on kinetochores, protein complexes on chromosomes. The central question is what forces drive chromosome segregation. The current model for human cells includes shortening of kinetochore fibers and separation of spindle poles. Both processes require kinetochore to be linked with the poles. Here we show, by combining live- cell imaging, laser ablation, photoactivation and theoretical modeling, that kinetochores can separate without the attachment to the spindle pole. this separation requires a microtubule fiber that connects a pair of sister k-fibers, known as the bridging fiber. Microtubules in the bridging fiber and sister k-fibers slide apart with the same velocity, indicating that these fibers are strongly crosslinked. Kinetochore segregation and pole separation is slowed down by depletion of MKLP1/KIF23 (kinesin-6), accelerated by depletion of KIF4A (kinesin-4), and unaffected by inhibition of Eg5/KIF11 (kinesin-5) or depletion of KIF15/Hklp2 (kinesin-12). We conclude that motor-driven sliding in the bridging fiber pushes k-fibers poleward by the friction of passive crosslinks between these fibers. thus, our work suggest that the contribution of forces from crosslinking k-fiber and non-k-fiber microtubules is an important aspect of mitosis.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

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