Related Experiment Video
Updated: Jun 11, 2026

Evaluation of Planar-Cell-Polarity Phenotypes in Ciliopathy Mouse Mutant Cochlea
Published on: February 21, 2016
ASPP2 regulates epithelial cell polarity through the PAR complex
Weili Cong1, Tomonori Hirose, Yutaka Harita
1Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fuku-ura, Kanazawa-ku, Yokohama, Japan.
Abstract:
The PAR complex, consisting of the evolutionarily conserved PAR-3, PAR-6, and aPKC, regulates cell polarity in many cell types, including epithelial cells [1-4]. Consistently, genetic manipulation of its components affects tissue integrity in multiple biological systems [5-9]. However, the regulatory mechanisms of the PAR complex remain obscure. We report here that apoptosis-stimulating protein of p53 (ASPP2 or TP53BP2), which binds to the tumor suppressor p53 and stimulates its proapoptotic function [10-12], positively regulates epithelial cell polarity by associating with the PAR complex. ASPP2 interacts and colocalizes with PAR-3 at apical cell-cell junctions in the polarized epithelial cells. Depletion of ASPP2 in epithelial cells causes defects in cell polarity, such as the formation of tight junctions and the maintenance and development of apical membrane domains. Moreover, depletion of ASPP2 causes a defect in PAR-3 localization, as well as vice versa. Furthermore, disturbance in the interaction between ASPP2 and PAR-3 causes defects in cell polarity. We conclude that ASPP2 regulates epithelial cell polarity in cooperation with PAR-3 to form an active PAR complex. Our results, taken together with the known functions of ASPP2, suggest a close relationship between cell polarity and other cell regulatory mechanisms mediated by ASPP2.
More Related Videos
12:15The C. elegans Intestine As a Model for Intercellular Lumen Morphogenesis and In Vivo Polarized Membrane Biogenesis at the Single-cell Level: Labeling by Antibody Staining, RNAi Loss-of-function Analysis and Imaging
Published on: October 3, 2017
05:50Measuring Cell-Edge Protrusion Dynamics during Spreading using Live-Cell Microscopy
Published on: November 1, 2021
Related Concept Videos
Cell Polarization by Rho Proteins
Mechanism of Filopodia Formation
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Polarity of the Cytoskeleton
Separation of Sister Chromatids
At the onset of anaphase, separase, a proteolytic enzyme, is...
Mechanism of Lamellipodia Formation