Introduction 
this case, the extracellular matrix helps to pro- 
vide the body's architectural framework. 
Cellular adhesion, which plays a crucial role 
in cell, tissue, and organ structure and in cell 
movements, depends on specialized cell adhe- 
sion receptors that are connected to the intracel- 
lular cytoskeleton. It is also likely that cells can 
signal to one another via cell adhesion receptors. 
Decisions as to whether a cell remains stationary, 
or where and when it should move, and what 
shape it should take up, are all affected by cell 
adhesion events. And these, in turn, are largely 
dependent on the pattern and functions of cell 
adhesion receptors deployed on the surfaces of 
the cells. 
Elucidating the normal functions of cells is an 
important first step in understanding how these 
processes go awry in a number of human diseases . 
For example, it is now known that alterations in 
certain normal genes (called oncogenes) can 
contribute to cancer. It is also clear that many 
oncogenes encode proteins that are involved in 
the regulation of specific cellular functions: 
some oncogene-encoded proteins are growth fac- 
tors; others are cell surface receptors; yet others 
are signaling molecules, protein kinases, and 
transcription factors. Many other human diseases 
are known to be due to defects of one or another 
of the cellular processes reviewed above. Thus 
disturbances in insulin production lead to dia- 
betes mellitus, defects in the extracellular matrix 
can cause osteogenesis imperfecta, and abnormal- 
ities in cell adhesion receptors may result in 
various bleeding disorders. Indeed, one of the 
major insights in pathology and medicine is that 
all disease processes are ultimately attributable 
to the breakdown of one or more cellular func- 
tions. In the twenty-first century, we can be fairly 
certain that medicine will be concerned largely 
with the identification and treatment of specific 
disordered cell functions. We already know of 
many disorders that can be attributed to distur- 
bances in particular organelles. What is particu- 
larly encouraging to researchers in cell biology 
today is that new avenues are beginning to be 
perceived for therapy, as the molecular bases of 
various disordered functions become known. In- 
deed, one of the especially appealing aspects of 
modern cell biological research is the imme- 
diacy with which fundamental research advances 
are having an impact on medically important 
problems. 
Investigators in the Cell Biology and Regulation Program 
Alexander-Bridges, Maria C, M.D., Ph.D. 
Beach, David H., Ph.D. 
Bennett, G. Vann, M.D., Ph.D. 
Beutler, Bruce A., M.D. 
Bevilacqua, Michael P., M.D., Ph.D. 
Blackshear, Perry J., M.D., D.Phil. 
Blobel, Gunter, M.D., Ph.D. 
Bonadio, Jeffrey F., M.D. 
Brugge, Joan S., Ph.D. 
Campbell, Kevin P., Ph.D. 
Caron, Marc G., Ph.D.' 
Carroll, Sean B., Ph.D. 
Chin, William W., M.D. 
Crab tree, Gerald R., M.D. 
Craig, Nancy L., Ph.D. 
Cunningham, James M., M.D. 
Davis, Laura I., Ph.D. 
Davis, Roger J., M.D. 
Dreyfuss, Gideon, Ph.D. 
Emr, Scott D., Ph.D. 
Esmon, Charles T., Ph.D. 
Exton, John H., M.D., Ph.D. 
Fuchs, Elaine, Ph.D. 
Ganem, Donald E., M.D. 
Garbers, David L., Ph.D. 
Gething, Mary-Jane H., Ph.D. 
Glomset, John A., M.D. 
Gomer, Richard H., Ph.D. 
Grosschedl, Rudolf, Ph.D. 
Habener, Joel F., M.D. 
Heintz, Nathaniel, Ph.D. 
Hynes, Richard O., Ph.D. 
Isberg, Ralph R., Ph.D. 
Kaback, H. Ronald, M.D. 
Kim, Peter S., Ph.D. 
Kirkegaard, Karla A., Ph.D. 
Kobilka, Brian K, M.D. 
Lai, Michael M.-C, M.D., Ph.D. 
Lamb, Robert A., Ph.D., Sc.D. 
Lefkowitz, Robert /., M.D. 
Lehmann, Ruth, Ph.D. 
Maas, Richard L., M.D., Ph.D. 
Mailer, James L., Ph.D. 
Massague, Joan, Ph.D. 
McKnigbt, Steven Lanier, Ph.D. 
Nusse, Roel, Ph.D. 
O'Donnell, Michael E., Ph.D. 
Parker, Keith L., M.D., Ph.D. 
Pike, Linda J., Ph.D. 
Sadler, J. Evan, M.D., Ph.D. 
Schekman, Randy W., Ph.D. 
Schoolnik, Gary K., M.D. 
Shenk, Thomas E., Ph.D. 
Sherr, Charles J., M.D., Ph.D. 
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