Article

Multicellular rosette formation links planar cell polarity to tissue morphogenesis.

Developmental Biology Program, Sloan-Kettering Institute, New York, New York 10021, USA.
Developmental Cell (Impact Factor: 10.37). 11/2006; 11(4):459-70. DOI: 10.1016/j.devcel.2006.09.007
Source: PubMed

ABSTRACT Elongation of the body axis is accompanied by the assembly of a polarized cytoarchitecture that provides the basis for directional cell behavior. We find that planar polarity in the Drosophila embryo is established through a sequential enrichment of actin-myosin cables and adherens junction proteins in complementary surface domains. F-actin accumulation at AP interfaces represents the first break in planar symmetry and occurs independently of proper junctional protein distribution at DV interfaces. Polarized cells engage in a novel program of locally coordinated behavior to generate multicellular rosette structures that form and resolve in a directional fashion. Actin-myosin structures align across multiple cells during rosette formation, and adherens junction proteins assemble in a stepwise fashion during rosette resolution. Patterning genes essential for axis elongation selectively affect the frequency and directionality of rosette formation. We propose that the generation of higher-order rosette structures links local cell interactions to global tissue reorganization during morphogenesis.

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