Abstract
The checkpoint protein Chfr delays entry into mitosis in the presence of mitotic stress. We have analyzed the Chfr checkpoint pathway in the Xenopus cell-free system. We showed that Chfr is a ubiquitin ligase that targets polo-like kinase (Plk1) for degradation, leading to delayed activation of the Cdc25C phosphatase and prolonged inhibitory phosphorylation of Cdc2 at the G2/M transition. In this chapter, we will describe biochemical methods we developed to analyze the Chfr auto-ubiquitination activity and the ubiquitination of its substrate Plk1, as well as functional assays to investigate the Chfr pathway in Xenopus extracts.
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© 2004 Humana Press Inc.
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Kang, D., Wong, J., Fang, G. (2004). A Xenopus Cell-Free System for Functional Analysis of the Chfr Ubiquitin Ligase Involved in Control of Mitotic Entry. In: Schönthal, A.H. (eds) Checkpoint Controls and Cancer. Methods in Molecular Biology™, vol 280. Humana Press. https://doi.org/10.1385/1-59259-788-2:229
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DOI: https://doi.org/10.1385/1-59259-788-2:229
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