We request partial support for a Federation of American Biological Societies of Experimental Biology (FASEB) conference entitled 'Protein Lipidation, Signaling and Membrane Domains,'to be held July 24-29, 2004 at Tucson, AZ. This meeting will highlight exciting recent progress, and provide a needed forum for critical discussions, concerning lipid-modified proteins and membrane microdomains and their roles in processes including signal transduction, trafficking of membrane molecules and disease pathogenesis. The meeting will be organized around three main themes. First, it will provide a very timely opportunity for the exchange and critical evaluation of information about the nature of membrane microdomains in living cells and their roles in functions such as cell signaling and membrane trafficking. Recent work in these areas has generated much excitement but has also clearly indicated a need for more rigorous, multifaceted strategies to address these issues. Second, the conference will highlight recent evidence that lipid-modified proteins and membrane domains play important roles in the pathogenesis of cancer, infectious diseases and inherited disorders, and it will present current progress in the development of inhibiters of protein lipidation as potential therapeutic agents for the treatment of cancer (protein prenyltransferase inhibitors) and parasitic infections (inhibitors of enzymes involved in protein myristoylation and glycosylphosphatidylinositol [GPI-] anchorage). Finally, the meeting will feature new developments in understanding the enzymology of protein lipidation, including recent successes in characterizing the enzymes involved in coupling S-acyl and GPIanchor'groups to proteins, using combined genetic and biochemical approaches. With its unique dual focus on the complementary areas of lipid-modified proteins and membrane microdomains, this meeting will promote important sharing of information by researchers from fields ranging from biophysics and structural biology to immunology and cancer biology.