Basis of lethality in C. elegans lacking CUP-5, the Mucolipidosis Type IV orthologue.
Mutations in MCOLN1, which encodes the protein h-mucolipin-1, result in the lysosomal storage disease Mucolipidosis Type IV. Studies on CUP-5, the human orthologue of h-mucolipin-1 in Caenorhabditis elegans, have shown that these proteins are required for lysosome biogenesis. We show here that the lethality in cup-5 mutant worms is due to two defects, starvation of embryonic cells and general developmental defects. Starvation leads to apoptosis through a CED-3-mediated pathway. We also show that providing worms with a lipid-soluble metabolite partially rescues the embryonic lethality but has no effect on the developmental defects, the major cause of the lethality. These results indicate that supplementing the metabolic deficiency of Mucolipidosis Type IV patients mat not be sufficient to alleviate the symptoms due to tissue degeneration.
Schaheen
Lara
L
Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA.
Dang
Hope
H
Fares
Hanna
H
D000255:Adenosine Triphosphate / Q000378:metabolism; D000483:Alleles; D000818:Animals; D030801:Animals, Genetically Modified; D001343:Autophagy; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D017238:Genes, Helminth; D005804:Genes, Lethal; D006801:Humans; D008565:Membrane Proteins / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism; D008954:Models, Biological; D009081:Mucolipidoses / Q000235:genetics*; D009154:Mutation; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D051880:Receptors, Notch; D050053:TRPM Cation Channels / Q000235:genetics; D050051:Transient Receptor Potential Channels
C426649:CUP-5 protein, C elegans; D029742:Caenorhabditis elegans Proteins; C082460:Lin-12 protein, C elegans; C416674:MCOLN1 protein, human; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D051880:Receptors, Notch; D050053:TRPM Cation Channels; D050051:Transient Receptor Potential Channels; D000255:Adenosine Triphosphate