Abstract: The presently-disclosed IPC synthase-inhibitor assays comprise the steps of: (1) expression of the IPC1 gene in a cell; (2) introducing labeled starting substrates for ceramide conversion as well as potential inhibitor(s) of such conversion to the expressed gene product in an environment which allows time and conditions for conversion, and (3) identifying those potential inhibitors which actually inhibit conversion.

Abstract: A method for specifying a fatty acid at the sn2 position of acylglycerol lipids including (a) transfecting a vector including the SLC1 gene or a variant thereof into embryonic biological material, and (b) allowing the SLC1 gene to specify the type of fatty acid at the sn2 position of acylglycerol lipids. Also provided for is an isolated SLC1 gene and a probe for its detection.

Abstract: The invention provides the LCB1 and LCB2 genes of the yeast Saccharomyces cerevisiae that encode subunits of the enzyme serine palmitoyltransferase (SPT), the first enzyme leading to synthesis of the long-base component of the sphingolipids. The present specification describes the isolation of the LCB1 and LCB2 genes. The invention further relates to methods of using these genes to either inhibit SPT activity or to inhibit synthesis of the enzyme. Furthermore, the invention relates to methods for constructing strains of S. cerevisiae or other organisms that can be used to select and to test for compounds that either inhibit SPT activity or to inhibit synthesis of the enzyme.

Abstract: The invention relates to novel, transformed strains of Lac.sup.+ Saccharomyces cerevisiae, capable of utilizing lactose as a sole carbon source, produced by inserting into the Saccharomyces cerevisiae a plasmid containing a lactose permease and a beta-galactosidase gene derived from Kluyveromyces lactis yeast.