Abstract

Now that whole genome sequences are available for many eukaryotic organisms from yeast to man, we can form broad hypotheses on the basis of the relative expansion of protein families. To investigate the molecular mechanisms responsible for the organization of membrane compartments, we identified members of the SNARE, coat complex, Rab and Sec1 protein families in four eukaryotic genomes. Of these families only the Rab family expanded from the unicellular yeast to the multicellular fly and worm. All families were expanded in humans, where we find 35 SNAREs, 60 Rabs and 53 coat complex subunits. In addition, we were able to resolve the SNARE class of proteins into four distinct subfamilies.

1. Howard Hughes Medical Institute, Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305-5426, USA

Correspondence to: Richard H. Scheller Correspondence and requests for materials should be addressed to R.H.S. (e-mail: Email: scheller@cmgm.stanford.edu).