Dr. Maller’s laboratory studies the molecular regulation of decision points in the cell cycle during which commitments are made to initiate DNA synthesis and centrosome duplication and to enter or exit mitosis. Checkpoint decisions are regulated by integrated signals that control the activity of protein kinases and phosphatases that regulate key enzymes involved in cell cycle control. A current focus in the lab is on Greatwall kinase, which has key functions in entry into mitosis and in recovery from DNA damage. The laboratory is also interested in kinase-dependent mechanisms of centrosome amplification, both by over-duplication and by de novo generation. Xenopus oocytes, embryos, and egg extracts are used as model systems that complement conventional approaches in cultured cells.