Selection and phylogenetic analysis of candidate CPE synthases.
A, reaction chemistry of PE and CPE biosynthesis in mammals and insects. See “Results and Discussion” for further details. DAG, diacylglycerol. B, phylogenetic tree of proteins in insects, Caenorhabditis elegans, human, and yeast containing a CAPT motif. The four candidate CPE synthases in Drosophila are marked dCCS1–4. The protein sequences were aligned with DIALIGN 2 (33) with manual editing to ensure correct alignment of the conserved pattern, D(X)2DG(X)2(A/Y)R(X)8–16G(X)3D(X)3D. Alignment columns with a quality score of 4 or better were used to draw a phylogenetic tree with Protdist and Fitch from the PHYLIP package. The tree was displayed and edited with TreeIllustrator (34). NCBI GI numbers are: 1) 110750730 (translation of bases 327125–328027); 2) 158033532 (translation of bases 2339192–2338023); 3) O77475; 4) 6320059; 5) 23172318; 6) 10092647; 7) 71984834; 8) 6325370; 9) 17537129; 10) 5453906; 11) 24642243; 12) 6321915; 13) 42742307; 14) 50083289; 15) 28574275; 16) 28574587; 17) 71986977; 18) 193209951; 19) 115534720; 20) 50726996; 21) 24653393; 22) 5174415.