Naslov
PRC1‐labeled microtubule bundles and kinetochore pairs show one‐to‐one association in metaphase

Autori
Polak, Bruno ; Risteski, Patrik ; Lesjak, Sonja ; Tolić, Iva Marija

Izvornik
EMBO reports (1469-221X) 18 (2017); 217-230

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

Ključne riječi
bridging fiber ; interpolar microtubules ; K‐fiber ; mitosis ; overlap microtubules

Sažetak
In the mitotic spindle, kinetochore microtubules form k‐fibers, whereas overlap or interpolar microtubules form antiparallel arrays containing the cross‐linker protein regulator of cytokinesis 1 (PRC1). We have recently shown that an overlap bundle, termed bridging fiber, links outermost sister k‐fibers. However, the relationship between overlap bundles and k‐fibers throughout the spindle remained unknown. Here, we show that in a metaphase spindle more than 90% of overlap bundles act as a bridge between sister k‐fibers. We found that the number of PRC1‐GFP‐labeled bundles per spindle is nearly the same as the number of kinetochore pairs. Live‐cell imaging revealed that kinetochore movement in the equatorial plane of the spindle is highly correlated with the movement of the coupled PRC1‐GFP‐labeled fiber, whereas the correlation with other fibers decreases with increasing distance. Analysis of endogenous PRC1 localization confirmed the results obtained with PRC1‐GFP. PRC1 knockdown reduced the bridging fiber thickness and interkinetochore distance throughout the spindle, suggesting a function of PRC1 in bridging microtubule organization and force balance in the metaphase spindle.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

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