학술논문

Par3 integrates Tiam1 and phosphatidylinositol 3-kinase signaling to change apical membrane identity
Document Type
article
Source
Molecular Biology of the Cell. 28(2)
Subject
Biochemistry and Cell Biology
Biological Sciences
Adaptor Proteins
Signal Transducing
Animals
Cell Culture Techniques
Cell Cycle Proteins
Cell Membrane
Cell Movement
Cell Polarity
Dogs
Guanine Nucleotide Exchange Factors
Humans
Madin Darby Canine Kidney Cells
Membrane Proteins
Phosphatidylinositol 3-Kinase
Protein Transport
Signal Transduction
T-Lymphoma Invasion and Metastasis-inducing Protein 1
Tight Junctions
rac1 GTP-Binding Protein
Medical and Health Sciences
Developmental Biology
Biochemistry and cell biology
Language
Abstract
Pathogens can alter epithelial polarity by recruiting polarity proteins to the apical membrane, but how a change in protein localization is linked to polarity disruption is not clear. In this study, we used chemically induced dimerization to rapidly relocalize proteins from the cytosol to the apical surface. We demonstrate that forced apical localization of Par3, which is normally restricted to tight junctions, is sufficient to alter apical membrane identity through its interactions with phosphatidylinositol 3-kinase (PI3K) and the Rac1 guanine nucleotide exchange factor Tiam1. We further show that PI3K activity is required upstream of Rac1, and that simultaneously targeting PI3K and Tiam1 to the apical membrane has a synergistic effect on membrane remodeling. Thus, Par3 coordinates the action of PI3K and Tiam1 to define membrane identity, revealing a signaling mechanism that can be exploited by human mucosal pathogens.