在分裂過程中，真核細胞需要在兩個子細胞之間準確分配其遺傳材料。這個過程涉及微管有絲分裂紡錘體與染色體上被稱為「著絲點」的專門區域的相互作用。Alushin等人介紹了對微管與「著絲點」的一個必要蛋白成分「Ndc80複合物」的相互作用的一項冷電子顯微鏡重建研究。所獲結構顯示，「Ndc80複合物」自身寡聚成線性陣列，後者在微管上形成一種套管一樣的覆蓋物，這樣一種排列能夠讓染色體穿過微管的內在動態系統。「Ndc80複合物」與微管之間這種相互作用的性質，提出了Aurora B激酶對「著絲點」/微管相互作用進行磷調控的一個機制。。（生物谷 Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature09423
The Ndc80 kinetochore complex forms oligomeric arrays along microtubules
Gregory M. Alushin,Vincent H. Ramey,Sebastiano Pasqualato,David A. Ball,Nikolaus Grigorieff,Andrea Musacchio& Eva Nogales
The Ndc80 complex is a key site of regulated kinetochore–microtubule attachment (a process required for cell division), but the molecular mechanism underlying its function remains unknown. Here we present a subnanometre-resolution cryo-electron microscopy reconstruction of the human Ndc80 complex bound to microtubules, sufficient for precise docking of crystal structures of the component proteins. We find that the Ndc80 complex binds the microtubule with a tubulin monomer repeat, recognizing α- and β-tubulin at both intra- and inter-tubulin dimer interfaces in a manner that is sensitive to tubulin conformation. Furthermore, Ndc80 complexes self-associate along protofilaments through interactions mediated by the amino-terminal tail of the NDC80 protein, which is the site of phospho-regulation by Aurora B kinase. The complex’s mode of interaction with the microtubule and its oligomerization suggest a mechanism by which Aurora B could regulate the stability of load-bearing kinetochore–microtubule attachments.