CENP-E combines a slow, processive motor and a flexible coiled coil to produce an essential motile kinetochore tether |
| |
Authors: | Kim Yumi Heuser John E Waterman Clare M Cleveland Don W |
| |
Institution: | Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA. |
| |
Abstract: | The mitotic kinesin centromere protein E (CENP-E) is an essential kinetochore component that directly contributes to the capture and stabilization of spindle microtubules by kinetochores. Although reduction in CENP-E leads to high rates of whole chromosome missegregation, neither its properties as a microtubule-dependent motor nor how it contributes to the dynamic linkage between kinetochores and microtubules is known. Using single-molecule assays, we demonstrate that CENP-E is a very slow, highly processive motor that maintains microtubule attachment for long periods. Direct visualization of full-length Xenopus laevis CENP-E reveals a highly flexible 230-nm coiled coil separating its kinetochore-binding and motor domains. We also show that full-length CENP-E is a slow plus end-directed motor whose activity is essential for metaphase chromosome alignment. We propose that the highly processive microtubule-dependent motor activity of CENP-E serves to power chromosome congression and provides a flexible, motile tether linking kinetochores to dynamic spindle microtubules. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|