Data are collected from Nature, Science, Cell, and Nature Cell Biology to form a database and resource for studying the signaling pathways of human cells. The site has a great search facility that allows you to find which pathways a given protein is part of, along with upstream and downstream effectors, other family members and other signaling proteins found in the same tissue and/or subcellular site. The site can be browsed by category of protein or by pathway (ranging from apoptosis to Wnt signaling). Clickable diagrams of a vast range of signaling pathways are linked to functional information. Some of the images are very large and, as a result, are truncated when printed out. There are few external links, although some references are linked to PubMed and there are also links to the Protein data bank (PDB) coordinate files. To download and view the latter you need the Chemscape plugin software.
Most pages have a menu at the bottom, making general navigation around the site relatively easy. Deep layers of links from a molecule's starting page, however, can make it very easy to get lost. A way of returning to this starting page would be very useful. Not all pages can be bookmarked.
The site appears to be timely and was last updated 17 November 1999.
The power of this site lies in the ability to obtain large quantities of information from a simple search by protein name.
It is not always apparent what type of information the links are pointing to, or what the search facilities do - the only way to find out is to follow the link.
The pages would benefit from greater annotation explaining what the various features are and what the links point to, as well as a 'home' button and universal bookmarking.