Isopentenyl-diphosphate isomerase is essential for viability of Caenorhabditis elegans.
Homozygosity for a mutation in the idi-1 gene of Caenorhabditis elegans results in paralysis during the first larval stage, followed by an arrest of growth and development late in the first larval stage. Apoptotic corpses, which are apparently the result of normal programmed cell death, persist in the arrested larvae. In genetic mosaics, an additional defect becomes evident upon examination with Nomarski optics: cells that are genotypically mutant enlarge, and their cytoplasm becomes dimpled. Electron microscopy indicates that the dimpling reflects an accumulation of many enlarged lysosomes and autophagosomes. The mosaics demonstrate that the lethal mutation acts cell autonomously with respect to this vesicular abnormality and that there is a maternal effect with respect to the time of developmental arrest of mutant progeny. Cloning of the gene reveals that it is the only gene in C. elegans for isopentenyl-diphosphate isomerase, an enzyme that is important for the synthesis of lipophilic molecules, including farnesyl and geranyl diphosphates.
Yochem
John
J
Department of Genetics, Cell Biology and Development, University of Minnesota, 6-160 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, USA. yoche001@umn.edu
Hall
David H
DH
Bell
Leslie R
LR
Hedgecock
Edward M
EM
Herman
Robert K
RK
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D019748:Carbon-Carbon Double Bond Isomerases / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000648:ultrastructure; D017931:DNA Primers; D045782:Hemiterpenes; D008247:Lysosomes / Q000648:ultrastructure; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D017422:Sequence Analysis, DNA
D017931:DNA Primers; D045782:Hemiterpenes; D019748:Carbon-Carbon Double Bond Isomerases; C021453:isopentenyldiphosphate delta-isomerase