Cytoplasmic dynein light intermediate chain is required for discrete aspects of mitosis in Caenorhabditis elegans.
We describe phenotypic characterization of dli-1, the Caenorhabditis elegans homolog of cytoplasmic dynein light intermediate chain (LIC), a subunit of the cytoplasmic dynein motor complex. Animals homozygous for loss-of-function mutations in dli-1 exhibit stochastic failed divisions in late larval cell lineages, resulting in zygotic sterility. dli-1 is required for dynein function during mitosis. Depletion of the dli-1 gene product through RNA-mediated gene interference (RNAi) reveals an early embryonic requirement. One-cell dli-1(RNAi) embryos exhibit failed cell division attempts, resulting from a variety of mitotic defects. Specifically, pronuclear migration, centrosome separation, and centrosome association with the male pronuclear envelope are defective in dli-1(RNAi) embryos. Meiotic spindle formation, however, is not affected in these embryos. DLI-1, like its vertebrate homologs, contains a putative nucleotide-binding domain similar to those found in the ATP-binding cassette transporter family of ATPases as well as other nucleotide-binding and -hydrolyzing proteins. Amino acid substitutions in a conserved lysine residue, known to be required for nucleotide binding, confers complete rescue in a dli-1 mutant background, indicating this is not an essential domain for DLI-1 function.
Yoder
J H
JH
Department of Molecular, Cellular, and Developmental Biology, Howard Hughes Medical Institution, University of Colorado, Boulder, 80303-0347, USA.
Han
M
M
D000483:Alleles; D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology* / Q000196:embryology; D029742:Caenorhabditis elegans Proteins; D018385:Centrosome / Q000502:physiology*; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000201:enzymology; D004398:Dyneins / Q000235:genetics* / Q000378:metabolism*; D008540:Meiosis / Q000502:physiology; D008938:Mitosis / Q000502:physiology*; D008969:Molecular Sequence Data; D009685:Nuclear Envelope / Q000378:metabolism; D010641:Phenotype; D017354:Point Mutation; D017434:Protein Structure, Tertiary / Q000235:genetics; D021122:Protein Subunits; D016415:Sequence Alignment; D008941:Spindle Apparatus
D029742:Caenorhabditis elegans Proteins; D021122:Protein Subunits; C444431:Dli-1 protein, C elegans; D004398:Dyneins