Acknowledgements

This presentation is based mainly on the work of Milburn, et al. (1990) Science 247, 939-945 (medline entry).

The RAS·GTP structure is PDB* entry 6Q21 and the RAS·GDP complex is PDB entry 4Q21.

I used the Swiss PDB viewer to align the two RAS structures and to write a merged file for use in the section on conformational changes. I thank Gale Rhodes of the University of Southern Maine for making me aware (via the Rasmol list serve) of this wonderful program and specifically its ability to align two structures in three dimensions.

* Protein Databank