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Science 300 (5618): 445-452

Copyright © 2003 by the American Association for the Advancement of Science

Assembly of Cell Regulatory Systems Through Protein Interaction Domains

Tony Pawson1,2*, and Piers Nash1

Abstract: The sequencing of complete genomes provides a list that includes the proteins responsible for cellular regulation. However, this does not immediately reveal what these proteins do, nor how they are assembled into the molecular machines and functional networks that control cellular behavior. The regulation of many different cellular processes requires the use of protein interaction domains to direct the association of polypeptides with one another and with phospholipids, small molecules, or nucleic acids. The modular nature of these domains, and the flexibility of their binding properties, have likely facilitated the evolution of cellular pathways. Conversely, aberrant interactions can induce abnormal cellular behavior and disease. The fundamental properties of protein interaction domains are discussed in this review and in detailed reviews on individual domains at Science's STKE at http://www.sciencemag.org/cgi/content/full/300/5618/445/DC1.

1 Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada.
2 Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.

* To whom correspondence should be addressed. E-mail: pawson{at}mshri.on.ca

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