Regulated Activation of the PAR Polarity Network Ensures a Timely and Specific Response to Spatial Cues.

ABSTRACT: How do cells polarize at the correct time and in response to the correct cues? In the C. elegans zygote, the timing and geometry of polarization rely on a single dominant cue-the sperm centrosome-that matures at the end of meiosis and specifies the nascent posterior. Polarization requires that the conserved PAR proteins, which specify polarity in the zygote, be poised to respond to the centrosome. Yet, how and when PAR proteins achieve this unpolarized, but responsive, state is unknown. We show that oocyte maturation initiates a fertilization-independent PAR activation program. PAR proteins are initially not competent to polarize but gradually acquire this ability following oocyte maturation. Surprisingly, this program allows symmetry breaking even in unfertilized oocytes lacking centrosom

SUBMITTER: Reich JD 

PROVIDER: S-EPMC6584329 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature