The PDZ domain of the guanine nucleotide exchange factor PDZGEF directs binding to phosphatidic acid during brush border formation

Sarah V Consonni; Patricia M Brouwer; Eleonora S van Slobbe; Johannes L Bos

doi:10.1371/journal.pone.0098253

The PDZ domain of the guanine nucleotide exchange factor PDZGEF directs binding to phosphatidic acid during brush border formation

PLoS One. 2014 May 23;9(5):e98253. doi: 10.1371/journal.pone.0098253. eCollection 2014.

Authors

Sarah V Consonni¹, Patricia M Brouwer¹, Eleonora S van Slobbe¹, Johannes L Bos¹

Affiliation

¹ Department of Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands.

Abstract

PDZGEF is a guanine nucleotide exchange factor for the small G protein Rap. It was recently found that PDZGEF contributes to establishment of intestinal epithelial polarity downstream of the kinase Lkb1. By binding to phosphatidic acid enriched at the apical membrane, PDZGEF locally activates Rap2a resulting in induction of brush border formation via a pathway that includes the polarity players TNIK, Mst4 and Ezrin. Here we show that the PDZ domain of PDZGEF is essential and sufficient for targeting PDZGEF to the apical membrane of polarized intestinal epithelial cells. Inhibition of PLD and consequently production of phosphatidic acid inhibitis targeting of PDZGEF to the plasma membrane. Furthermore, localization requires specific positively charged residues within the PDZ domain. We conclude that local accumulation of PDZGEF at the apical membrane during establishment of epithelial polarity is mediated by electrostatic interactions between positively charged side chains in the PDZ domain and negatively charged phosphatidic acid.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cell Membrane / genetics
Cell Membrane / metabolism
Cell Membrane / ultrastructure
Cell Polarity / physiology*
Guanine Nucleotide Exchange Factors / genetics
Guanine Nucleotide Exchange Factors / metabolism*
HEK293 Cells
Humans
Intestinal Mucosa / metabolism*
Intestinal Mucosa / ultrastructure
Microvilli / genetics
Microvilli / metabolism*
Microvilli / ultrastructure
Nerve Tissue Proteins / genetics
Nerve Tissue Proteins / metabolism*
Phosphatidic Acids / genetics
Phosphatidic Acids / metabolism*
rap GTP-Binding Proteins / genetics
rap GTP-Binding Proteins / metabolism

Substances

Guanine Nucleotide Exchange Factors
Nerve Tissue Proteins
Phosphatidic Acids
RAPGEF2 protein, human
RAPGEF6 protein, human
RAP2A protein, human
rap GTP-Binding Proteins

Grants and funding

This work is supported by Chemical Sciences (S.V.C.) and the Netherlands Genomics Initiative (J.L.B.) of the Netherlands Organization for Scientific Research (NWO). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.