Asymmetric segregation of PIE-1 in C. elegans is mediated by two complementary mechanisms that act through separate PIE-1 protein domains

Mol Cell. 2000 Aug;6(2):445-55. doi: 10.1016/s1097-2765(00)00043-5.


The CCCH finger protein PIE-1 is a regulator of germ cell fate that segregates with the germ lineage in early embryos. At each asymmetric division, PIE-1 is inherited preferentially by the germline daughter and is excluded from the somatic daughter. We show that this asymmetry is regulated at the protein level by two complementary mechanisms. The first acts before cell division to enrich PIE-1 in the cytoplasm destined for the germline daughter. The second acts after cell division to eliminate any PIE-1 left in the somatic daughter. The latter mechanism depends on PIE-1's first CCCH finger (ZF1), which targets PIE-1 for degradation in somatic blastomeres. ZF1s in two other germline proteins, POS-1 and MEX-1, are also degraded in somatic blastomeres, suggesting that localized degradation also acts on these proteins to exclude them from somatic lineages.

Publication types

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

MeSH terms

  • Actins / physiology
  • Animals
  • Animals, Genetically Modified
  • Caenorhabditis elegans / cytology
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins*
  • Cell Division / drug effects
  • Cytochalasin D / pharmacology
  • Embryo, Nonmammalian / cytology
  • Embryo, Nonmammalian / physiology
  • Green Fluorescent Proteins
  • Helminth Proteins / chemistry
  • Helminth Proteins / metabolism
  • Luminescent Proteins / analysis
  • Luminescent Proteins / genetics
  • Microtubules / physiology
  • Nocodazole / pharmacology
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / metabolism*
  • Zinc Fingers
  • Zygote / cytology
  • Zygote / physiology


  • Actins
  • Caenorhabditis elegans Proteins
  • Helminth Proteins
  • Luminescent Proteins
  • Nuclear Proteins
  • pie-1 protein, C elegans
  • Green Fluorescent Proteins
  • Cytochalasin D
  • Nocodazole