ABSTRACT
Extracts prepared from the eggs of the African clawed frog, Xenopus laevis, have been instrumental in elucidating mechanisms that underlie vertebrate cell division control and DNA replication. Egg extracts have the unique capacity to undergo cell cycle transitions in vitro, enabling biochemical dissection of the pathways involved. The extracts also contain components sufficient to generate thousands of nuclei per microliter through stockpiles of essential replication factors and substrates. Although the critical early applications of this experimental system to the study of cell division control occurred nearly 40 years ago, the Xenopus in vitro model continues to be relevant today: creative new applications are constantly being devised. In this chapter, the history and current applications of this powerful experimental model in the study of cell division control and DNA replication are discussed.
