DPL1 (YDR294C) notes

UniProt Q05567, sphinganine/sphingosine-1-phosphate lyase (EC 4.1.2.27), PLP-dependent, integral ER membrane, homo-oligomer [UniProt:Q05567].

• Cloned as BST1, the S1P lyase PMID:9334171; deletion -> sphingoid base sensitivity and S1P accumulation.
• Structure of Dpl1p and activity/substrate residues PMID:20696404.
• Committed step of phytosphingosine -> odd-chain fatty acid pathway (PHS-1-P -> 2-hydroxyhexadecanal) PMID:25345524.
• ER integral, oligomer [PMID:18487605 "confirm it as an integral endoplasmic reticulum-resident protein"; "we demonstrate that Dpl1p exists as an oligomer"].
• Nutrient deprivation response PMID:10329480; S1P-triggered Ca2+ influx is inhibited by Dpl1 PMID:11278643.

Pathway context

• YeastPathways reaction (sphinganine-1-P -> palmitaldehyde + phosphoethanolamine, EC 4.1.2.27) is correct, but the pathway is "sphingolipid biosynthesis (yeast)": Dpl1 is the irreversible exit (degradative) step of sphingoid base metabolism, so the inherited "sphingolipid biosynthetic process" BP is inappropriate; catabolic process is the right BP.
• Peroxisome HDA from PMID:35563734 (Dpl1 not mentioned in main text): likely a proteomic contaminant.