Cleaves phosphorylated sphingoid bases (PSBs), such as sphingosine-1-phosphate, into fatty aldehydes and phosphoethanolamine. Elevates stress-induced ceramide production and apoptosis (By similarity). Required for global lipid homeostasis in liver and cholesterol homeostasis in fibroblasts. Involved in the regulation of pro-inflammatory response and neutrophil trafficking. Modulates neuronal autophagy via phosphoethanolamine production which regulates accumulation of aggregate-prone proteins such as APP (By similarity). Seems to play a role in establishing neuronal contact sites and axonal maintenance (By similarity). sphinganine 1-phosphate = hexadecanal + phosphoethanolamine sphing-4-enine 1-phosphate = (2E)-hexadecenal + phosphoethanolamine Lipid metabolism; sphingolipid metabolism. Homodimer. Belongs to the group II decarboxylase family. Sphingosine-1-phosphate lyase subfamily.