PI(4,5)P forms dynamic cortical structures and directs actin distribution as well as polarity in embryos.

Asymmetric division is crucial for embryonic development and stem cell lineages. In the one-cell embryo, a contractile cortical actomyosin network contributes to asymmetric division by segregating partitioning-defective (PAR) proteins to discrete cortical domains. In the current study, we found that the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP) localizes to polarized dynamic structures in zygotes, distributing in a PAR-dependent manner along the anterior-posterior (A-P) embryonic axis.