Sphingosine-1-phosphate lyase has a central role in the development of Dictyostelium discoideum

Sphingosine-1-phosphate, a product of sphingomyelin degradation, is an impo rtant element of signal transduction pathways that regulate cell proliferat ion and cell death. We have demonstrated additional roles for sphingosine-1 -phosphate in growth and multicellular development. The specific disruption in Dictyostelium discoideum of the sphingosine-1-phosphate lyase gene, whi ch encodes the enzyme that catalyzes sphingosine-1-phosphate degradation, r esults in a mutant strain with aberrant morphogenesis, as well as an increa se in viability during stationary phase. The absence of sphingosine-1-phosp hate lyase affects multiple stages throughout development, including the cy toskeletal architecture of aggregating cells, the ability to form migrating slugs, and the control of cell type-specific gene expression and terminal spore differentiation. This pleiotropic effect, which is due to the loss of sphingosine-1-phosphate lyase, establishes sphingolipids as pivotal regula tory molecules in a wide range of processes in multicellular development.