Abstract

Every organism must have cells that can replicate indefinitely. Can the draft human genome sequence tell us how the cell cycle works and how it evolved? We studied two protein families—the cyclins and their partners the cyclin-dependent kinases (Cdks)—and a conserved regulatory circuit, the spindle checkpoint. Disappointingly, we discovered a few novel cyclins and no new Cdks or components of the spindle checkpoint, and could shed little light on the organization of the cell cycle.

1. Center for Genomics Research, and
2. Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA
3. BCMP and Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA

Correspondence to: Andrew W. Murray^1,2 Correspondence and requests for materials should be addressed to A. M. (e-mail: amurray@mcb.harvard.edu).