G proteins are required for spatial orientation of early cell cleavages in C. elegans embryos

Cell. 1996 Aug 23;86(4):619-29. doi: 10.1016/s0092-8674(00)80135-x.


Heterotrimeric G proteins are signal-transducing molecules activated by seven transmembrane domain receptors. In C. elegans, gpb-1 encodes the sole Gbeta subunit; therefore, its inactivation should affect all heterotrimeric G protein signaling. When maternal but no zygotic gpb-1 protein (GPB-1) is present, development proceeds until the first larval stage, but these larvae show little muscle activity and die soon after hatching. When, however, the maternal contribution of GPB-1 is also reduced, spindle orientations in early cell divisions are randomized. Cell positions in these embryos are consequently abnormal, and the embryos die with the normal number of cells and well-differentiated but abnormally distributed tissues. These results indicate that maternal G proteins are important for orientation of early cell division axes, possibly by coupling a membrane signal to centrosome position.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Base Sequence
  • Behavior, Animal / physiology
  • Caenorhabditis elegans / embryology*
  • Cell Compartmentation
  • Cell Division*
  • Cell Membrane / metabolism
  • Cleavage Stage, Ovum*
  • DNA Primers / chemistry
  • Fluorescent Antibody Technique, Indirect
  • GTP-Binding Proteins / physiology*
  • Helminth Proteins / physiology
  • Molecular Sequence Data
  • Morphogenesis
  • Signal Transduction
  • Spindle Apparatus / ultrastructure
  • Zygote / physiology


  • DNA Primers
  • Helminth Proteins
  • GTP-Binding Proteins