title: Genetics of Lipid-Storage Management in Caenorhabditis elegans Embryos.
abstract: Lipids play a pivotal role in embryogenesis as structural components of cellular membranes, as a source of energy, and as signaling molecules. On the basis of a collection of temperature-sensitive embryonic lethal mutants, a systematic database search, and a subsequent microscopic analysis of >300 interference RNA (RNAi)-treated/mutant worms, we identified a couple of evolutionary conserved genes associated with lipid storage in Caenorhabditis elegans embryos. The genes include cpl-1 (cathepsin L-like cysteine protease), ccz-1 (guanine nucleotide exchange factor subunit), and asm-3 (acid sphingomyelinase), which is closely related to the human Niemann-Pick disease-causing gene SMPD1. The respective mutant embryos accumulate enlarged droplets of neutral lipids (cpl-1) and yolk-containing lipid droplets (ccz-1) or have larger genuine lipid droplets (asm-3). The asm-3 mutant embryos additionally showed an enhanced resistance against C band ultraviolet (UV-C) light. Herein we propose that cpl-1, ccz-1, and asm-3 are genes required for the processing of lipid-containing droplets in C. elegans embryos. Owing to the high levels of conservation, the identified genes are also useful in studies of embryonic lipid storage in other organisms.
authors.affiliation: Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts University of Kiel, 24118 Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Schmökel
authors.affiliation: Institute of Genetics, Technical University (TU) Braunschweig, 38106 Germany.
authors.forename: Nadin
authors.initials: N
authors.lastname: Memar
authors.affiliation: Institute of Genetics, Technical University (TU) Braunschweig, 38106 Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Wiekenberg
authors.affiliation: Core Facility for Mass Spectrometry, Lipidomics and Metabolomics, Centre for Medical Research (ZMF), University of Graz, A-8010 Austria Omics Center Graz, A-8010 Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Trotzmüller
authors.affiliation: Institute of Genetics, Technical University (TU) Braunschweig, 38106 Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Schnabel
authors.affiliation: Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts University of Kiel, 24118 Germany sek@molprev.uni-kiel.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Döring
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D056668:Cathepsin L / Q000235:genetics / Q000378:metabolism*; D047108:Embryonic Development; D050356:Lipid Metabolism / Q000235:genetics*; D009154:Mutation; D034622:RNA Interference; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics / Q000378:metabolism*; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C549250:CCZ-1 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D033921:Vesicular Transport Proteins; C580861:ASM-3 protein, C elegans; D013108:Sphingomyelin Phosphodiesterase; C466023:CPL-1 protein, C elegans; D056668:Cathepsin L
keywords: C. elegans; embryo development; embryonic lipid droplets; essential genes; yolk