Chapter 7
Crystallographic Studies of PDZ Domain–Peptide
Interactions of the Scribble Polarity Module
Janesha C. Maddumage, Bryce Z. Stewart, Patrick O. Humbert,
and Marc Kvansakul
Abstract
The determination of high-resolution crystal structures of cell polarity regulatory proteins bound to their
functional interactors has proven to be invaluable for deciphering the underlying molecular mechanisms.
Here we describe methods to identify suitable complexes of cell polarity protein domains bound to
interacting ligands with subsequent preparation of such complexes for X-ray crystallographic analysis.
Key words Epithelial cell polarity, Scribble module, Structural biology, X-ray crystallography
1 Introduction
The asymmetric distribution of macromolecules into different
compartments within a cell is a phenomenon known as cell polarity,
and is essential for correct execution of a wide range of biological
processes in metazoans. There are four major types of polarity
including apical–basal polarity, planar cell polarity, front–rear polarity, and asymmetrical cell division [1]. Irrespective of their differences, one common feature central to these types of polarity is the
coordinated involvement of a highly conserved set of proteins
known as polarity regulators. Loss-of-function mutations in these
polarity regulators cause polarity loss contributing to the development of disease such as cancer [2].
The Scribble module is one of the key protein regulators
involved in the establishment and maintenance of apical–basal
polarity. It consists of three members, Scribble, Dlg, and Lgl,
with these proteins controlling epithelial polarity in conjunction
with two other key modules the Par and the Crumbs complexes
Jean-Paul Borg (ed.), PDZ Mediated Interactions: Methods and Protocols, Methods in Molecular Biology, vol. 2256,
https://doi.org/10.1007/978-1-0716-1166-1_7, © Springer Science+Business Media, LLC, part of Springer Nature 2021
Janesha C. Maddumage and Bryce Z. Stewart contributed equally to this work.
125
Crystallographic Studies of PDZ Domain–Peptide
Interactions of the Scribble Polarity Module
Janesha C. Maddumage, Bryce Z. Stewart, Patrick O. Humbert,
and Marc Kvansakul
Abstract
The determination of high-resolution crystal structures of cell polarity regulatory proteins bound to their
functional interactors has proven to be invaluable for deciphering the underlying molecular mechanisms.
Here we describe methods to identify suitable complexes of cell polarity protein domains bound to
interacting ligands with subsequent preparation of such complexes for X-ray crystallographic analysis.
Key words Epithelial cell polarity, Scribble module, Structural biology, X-ray crystallography
1 Introduction
The asymmetric distribution of macromolecules into different
compartments within a cell is a phenomenon known as cell polarity,
and is essential for correct execution of a wide range of biological
processes in metazoans. There are four major types of polarity
including apical–basal polarity, planar cell polarity, front–rear polarity, and asymmetrical cell division [1]. Irrespective of their differences, one common feature central to these types of polarity is the
coordinated involvement of a highly conserved set of proteins
known as polarity regulators. Loss-of-function mutations in these
polarity regulators cause polarity loss contributing to the development of disease such as cancer [2].
The Scribble module is one of the key protein regulators
involved in the establishment and maintenance of apical–basal
polarity. It consists of three members, Scribble, Dlg, and Lgl,
with these proteins controlling epithelial polarity in conjunction
with two other key modules the Par and the Crumbs complexes
Jean-Paul Borg (ed.), PDZ Mediated Interactions: Methods and Protocols, Methods in Molecular Biology, vol. 2256,
https://doi.org/10.1007/978-1-0716-1166-1_7, © Springer Science+Business Media, LLC, part of Springer Nature 2021
Janesha C. Maddumage and Bryce Z. Stewart contributed equally to this work.
125