DESCRIPTION: The field of lipid second messengers has catapulted to the forefront of signaling pathways in the past decade. Since the discovery that diacylglycerol serves as a ubiquitous second messenger that regulates the function of the protein kinase C family, the involvement of a vast repertoire of lipids and their breakdown products in transducing diverse signals has been clearly established. Now, pivotal questions are to identify and characterize: 1) the enzymes that produce the lipid second messengers; and 2) the protein targets of these second messengers. A flurry of recent advances in the characterization of lipid kinases and phospholipases that regulate the levels of these second messengers, as well as identification of novel lipid second messengers, indicate that this is a prime time to evaluate lipid signaling. Th goal of this meeting is to address recent advances in elucidating the structure, function and regulation of proteins that produce lipid second messengers, and proteins that are targets for second messengers. Three key aspects of the proposed meeting are:1) It is unique in that it will focus on structure, function and regulation of both the enzymes that produce lipid second messengers and the enzymes regulated by lipid second messengers. This meeting is most similar to the 1994 Keystone Meeting and will provide a timely update in this rapidly growing field. Other meetings have focused more on biophysical properties of lipids (Biophysics subgroup in 1995) or the membrane enzymology of lipases (ASBMB satellite in 1996). 2) It is multidisciplinary in that it interfaces structural, mechanistic and cell biological aspects of lipid signaling. The leading researchers in these fields will be invited to participate. 3) It will set the agenda for future direction in the blossoming field of lipid signaling, which will be invaluable to graduate students and postdoctoral fellows in embarking upon their own careers