FIGURE 3.

Amino acid sequence comparison of SMPDL3A with acid sphingomyelinase and SMPDL3B. The amino acid sequences of human SMPDL3A and close human homologs, SMPDL3B and aSMase (encoded by the SMPD1 gene), were aligned using ClustalW2. Asterisks indicate exact sequence matches, and colons indicate conservative substitutions. Known or predicted signaling regions are shaded in light gray and saposin domains in dark gray. Phosphodiesterase consensus motifs are indicated using open boxes. Conserved residues known or predicted to be involved in metal binding are indicated by M. Known or predicted N-linked glycosylation sites are indicated by N. The predicted glycosylphosphatidylinositol anchor attachment site at Ala-431 in SMPDL3B is indicated by a light gray shaded box. Uniprot sequence accession numbers are SMPDL3A:Q92484, SMPDL3B:Q92485, and aSMase:P17405.