Heads of Laboratories
Laboratory of Cell Cycle Genetics
Cell cycle control involves the precisely coordinated production and destruction of numerous proteins that activate cyclical events in cells from yeast to human beings. The regulation of these events has central significance to the process by which cells acquire an identity, as well as diseases including cancer, which results when cells ignore certain checkpoints for division. Dr. Cross uses a variety of approaches to investigate cell cycle control at the molecular level.
Using budding yeast as a model system, Dr. Cross uses both genetic and biochemical approaches to investigate the molecular basis of cell cycle control. He is looking to understand how critical regulatory proteins called cyclins control cell cycle progression, both through their timely degradation and through their ability to be highly selective of the molecules with which they interact. Other areas of study in the Cross lab are devoted to the development of mathematical models that represent control of the cell cycle and to the creation of single-cell imaging methods for regulation of gene expression and protein localization through the cell cycle. Members of his lab are also investigating the regulation and activity of a specific phosphatase, Cdc14, that counteracts cyclin activity during mitosis. The laboratory is interested in systematic approaches to cell cycle control, including mathematical modeling.
A recently initiated project concerns cell cycle control in the green alga Chlamydomonas, which is a good microbial genetic model for the plant superkingdom. Plant genetics is challenging because of long generation times, diploid genetics, and ancient polyploidizations that result in many genes being present in multiple functional copies, masking loss-of-function phenotypes. Chlamydomonas, with essentially a full plant genome with respect to core cell biology including cell cycle regulation, has almost all of its genes in single copy, is haploid, and is amenable to classic microbial genetics, as well as modern molecular methods. The lab plans to create a systematic collection of mutations in all genes involved in Chlamydomonas cell cycle control in order to begin focused studies on similarities and differences in eukaryotic cell cycle control across kingdoms.
Cell cycle control is of central concern in a number of diseases, including cancer, which results when certain cell division checkpoints are ignored and the cells divide without restraint. In other cells, such as stem cells, cell cycle control is even more tightly regulated and is critical to the process by which cell differentiation occurs. Dr. Cross’s studies are likely to have ramifications for both of these areas.
The Rockefeller University
Fred Hutchinson Cancer Research Center, 1985–1989
Assistant Professor, 1989–1993
Associate Professor, 1993–1995
Dean, Graduate Studies, 1999–2000
The Rockefeller University
Lucille P. Markey Scholar, 1988–1992
Lu, Y. and Cross, F.R. Periodic cyclin-Cdk activity entrains an autonomous Cdc14 release oscillator. Cell 141, 268–279 (2010).
Bai, L. et al. Nucleosome-depleted regions in cell-cycle-regulated promoters ensure reliable gene expression in every cell cycle. Dev. Cell 18, 544–555 (2010).
Charvin, G. et al. Origin of irreversibility of cell cycle start in budding yeast. PLoS Biol. 8, e1000284 (2010).
Drapkin, B.J. et al. Analysis of the mitotic exit control system using locked levels of stable mitotic cyclin. Mol. Syst. Biol. 5, 328 (2009).
Di Talia, S. et al. Daughter-specific transcription factors regulate cell size control in budding yeast. PLoS Biol. 7, e1000221 (2009).