Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2007 Aug 27;178(5):773–784. doi: 10.1083/jcb.200702138

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

Copyright © 2007, The Rockefeller University Press

This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).

PMC Copyright notice

Figure 7. — BubR1 kinase activity is essential for the efficient recruitment of APC onto kinetochores in Xenopus egg extracts. (A) BubR1-depleted egg extracts containing sperm nuclei were cycled through interphase and arrested with CSF activity at the following metaphase. Recombinant WT-BubR1 (top) or KD-BubR1 (bottom) was added. Kinetochore recruitment of BubR1 (left; red), APC (right), and microtubules (left; green) was visualized by immunofluorescence with specific antibodies. Chromatin was visualized with DAPI (left; blue). (B) Quantification of the relative BubR1 and APC intensity at kinetochores in A. Error bars represent SEM. (C) Immunoprecipitates with an APC antibody from BubR1-depleted CSF egg extracts containing sperm nuclei and supplemented with purified WT-BubR1 (lanes 1 and 2) or KD-BubR1 (lanes 3 and 4) and probed with APC (top), BubR1 (middle), and EB1 (bottom) antibodies. FL, extracts after immunoprecipitation; IP, immunoprecipitates. A threefold higher proportion of the bead-bound fraction relative to the depleted extracts was analyzed. (D) Model: BubR1 is recruited onto unattached kinetochores. Microtubule-associated proteins APC/EB1 bind to the plus ends of microtubules. After the initial capture of microtubules by kinetochores, the interaction between BubR1 and APC/EB1 stabilizes kinetochore microtubule attachment, in which BubR1 might directly phosphorylate APC. Bar, 10 μm.