Stabilization of cell polarity by the C. elegans RING protein PAR-2

Yingsong Hao, Lynn Boyd, Geraldine Seydoux

Research output: Contribution to journalArticlepeer-review


Asymmetric localization of PAR proteins is a hallmark of polarized cells, but the mechanisms that create PAR asymmetry are not well understood. In the C. elegans zygote, PAR asymmetry is initiated by a transient actomyosin contraction, which sweeps the PAR-3/PAR-6/PKC-3 complex toward the anterior pole of the egg. The RING finger protein PAR-2 accumulates in a complementary pattern in the posterior cortex. Here we present evidence that PAR-2 participates in a feedback loop to stabilize polarity. PAR-2 is a target of the PKC-3 kinase and is excluded from the anterior cortex by PKC-3-dependent phosphorylation. The RING domain of PAR-2 is required to overcome inhibition by PKC-3 and stabilize PAR-2 on the posterior cortex. Cortical PAR-2 in turn prevents PAR-3/PAR-6/PKC-3 from returning to the posterior, in a PAR-1- and PAR-5-dependent manner. Our findings suggest that reciprocal inhibitory interactions among PAR proteins stabilize polarity by reinforcing an initial asymmetry in PKC-3.

Original languageEnglish (US)
Pages (from-to)199-208
Number of pages10
JournalDevelopmental Cell
Issue number2
StatePublished - Feb 2006


  • Cellbio
  • Devbio
  • Proteins

ASJC Scopus subject areas

  • Molecular Biology
  • Biochemistry, Genetics and Molecular Biology(all)
  • Developmental Biology
  • Cell Biology


Dive into the research topics of 'Stabilization of cell polarity by the C. elegans RING protein PAR-2'. Together they form a unique fingerprint.

Cite this