A SPECIALIZED PATHWAY AFFECTING VIRULENCE GLYCOCONJUGATES OF LEISHMANIA

For virulence and transmission, the protozoan Leishmania must assemble a complex glycolipid on the cell surface, the lipophosphoglycan (LPG) . Functional complementation identified the gene LPG2, which encodes a n integral Golgi membrane protein implicated in intracellular compartm entalization of LPG biosynthesis. Ipg2(-) mutants lack only characteri stic disaccharide-phosphate repeats, normally present on both LPG and other surface or secreted molecules considered critical for infectivit y. In contrast, a related yeast gene, VAN2/VRG4, is essential and requ ired for general Golgi function. These results suggest that LPG2 parti cipates in a specialized virulence pathway, which may offer an attract ive target for chemotherapy.