Sticking to the facts

Recently, scientists have identified many proteins that are involved in cell adhesion — the methods by which cells stick to each other, or to the extracellular matrix that surrounds them. Now, for the first time, this information has been arranged in a comprehensive structural model called the ‘adhesome’ by the group of Benjamin Geiger and co-workers at the Weizmann Institute of Science in Israel, and Mount Sinai School of Medicine in the US¹.

The researchers consulted vast databases on the protein interactions involved in cell adhesion. The data were compiled in a computer-based network that considers individual molecules as nodes, connected by links that include ‘binding interactions’ and ‘modification interactions’.

The network includes 156 molecules connected by 690 interactions, with an average of 8.66 interactions per molecule. This extensive connectivity makes the adhesome robust to failures — the network stays complete even when one or more molecule is removed. Also, many of the interactions can be turned on or off by protein modifications, which appears to be important for regulating the assembly of these structures.

The adhesome model (www.adhesome.org) makes it easier to identify functional groups of molecules and common patterns of behavior. Most importantly, it may stimulate new hypotheses for experimental testing that could provide insight into human genetic diseases related to the adhesion system.