Sphingolipid profiling reveals differential functions of sphingolipid biosynthesis isozymes of Caenorhabditis elegans

• DOI: 10.1016/j.jlr.2024.100553
• Publication Date: 2024-05-03T03:02:53Z
• Authors: Hui Luo; Xue Zhao; Zi-Dan Wang; Gang Wu; Yu Xia; Meng-Qiu Dong; Yan Ma
• Keywords: Sphingolipid; Profiling (computer programming)

Multiple isozymes are encoded in the Caenorhabditis elegans genome for various sphingolipid biosynthesis reactions, but contributions of individual characterized only part. We developed a simple effective reversed-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) method that enables simultaneous identification and quantification ceramides (Cer), glucosylceramides (GlcCer), sphingomyelins (SM) from same MS run. Validating this profiling method, we show nearly all 47 quantifiable species found young adult worms were reduced upon RNA interference (RNAi) sptl-1 or elo-5, which both required synthesis id17:1 sphingoid base. also confirm HYL-1 HYL-2, not LAGR-1, constitute major ceramide synthase activity with different preference fatty acid substrates, CGT-3, CGT-1 CGT-2, plays role producing GlcCers. Deletion sms-5 hardly affected SM levels. RNAi sms-1, sms-2, sms-3 lowered abundance certain SMs an odd-numbered N-acyl chains (mostly C21 C23, without hydroxylation). Unexpectedly, sms-2 elevated subset containing even-numbered N-acyls. This suggests sphingolipids N-acyls could be regulated separately, sometimes opposite directions, those N-acyls, presumably monomethyl branched chain acyls. find levels kept balance GlcCers SMs. These findings underscore effectiveness RPLC-MS/MS studies C. biology.