Asymmetric cell division that produces daughter cells with distinct cell fates is a fundamental mechanism by which cellular diversity is produced. Most cells in C. elegans have the same anterior-posterior polarity in terms of localizations of Wnt signaling components such as β-catenin, and divide asymmetrically to produce a variety of cell types. We are studying how each cell knows the correct orientation, how it divides asymmetrically and how the daughter cells acquire specific cell fates. We are also studying mechanisms of cell invasion and secretion of basement membrane proteins.
Asymmetric localization of β-catenin before (A) and at telophase (B) of asymmetric division. Arrowheads indicate cell boundary. (C) Polarity orientation (arrows) of epithelial stem cells (light blue) is redundantly controlled by three Wnt molecules (CWN-1, CWN-2, EGL-20). Localization of a basement membrane protein in pharynx in wild type (D) and a mutant (E). In the mutant, the protein forms aggregation.
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