Screens for small-molecule modulators of biological pathways typically utilize cultured cell lines, purified proteins, or, recently, model organisms (e.g., zebrafish, Drosophila, C. elegans). Herein, we describe a method for using Xenopus laevis egg extract, a biologically active and highly tractable cell-free system that recapitulates a legion of complex chemical reactions found in intact cells. Specifically, we focus on the use of a luciferase-based fusion system to identify small-molecule modulators that affect protein turnover.
Xenopus egg extract Xenopus laevisCell-free Small molecules High-throughput screening Protein turnover Protein degradation
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We thank Laurie Lee for critical reading of the manuscript. M.R.B. is supported by a National Cancer Institute training grant (T32 CA119925). E.L. is supported by the National Institutes of Health (R01GM081635 and R01GM103926). R.Y. is supported by Award Number 8UL1TR000149 from the National Center for Advancing Translational Sciences and the CTRC P30 Cancer Center Support Grant from the National Cancer Institute (CA054174). S.R.H. is supported by the National Cancer Institute (P50 CA095103).
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