Naslov
The mitotic spindle is chiral due to torques within microtubule bundles

Autori
Novak, Maja ; Polak, Bruno ; Simunić, Juraj ; Boban, Zvonimir ; Kuzmić, Barbara ; Thomae, Andreas W ; Tolić, Iva Marija ; Pavin, Nenad

Izvornik
Nature Communications (2041-1723) 9 (2018); 3571, 10

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
mitosis ; mitotic spindle ; microtubules ; chirality ; torque ; kinesin-5

Sažetak
Mitosis relies on forces generated in the spindle, a micro- machine composed of microtubules and associated proteins. Forces are required for the congression of chromosomes to the metaphase plate and their separation in anaphase. However, besides forces, torques may exist in the spindle, yet they have not been investigated. Here we show that the spindle is chiral. Chirality is evident from the finding that microtubule bundles in human spindles follow a left-handed helical path, which cannot be explained by forces but rather by torques. Kinesin-5 (Kif11/Eg5) inactivation abolishes spindle chirality. Our theoretical model predicts that bending and twisting moments may generate curved shapes of bundles. We found that bundles turn by about −2 deg µm−1 around the spindle axis, which we explain by a twisting moment of roughly −10 pNµm. We conclude that torques, in addition to forces, exist in the spindle and determine its chiral architecture.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Biologija

POVEZANOST RADA