Structures of the human SPAK and OSR1 conserved C-terminal (CCT) domains

DOI: 10.1002/cbic.202100441

Authors: Karen T. Elvers (Cardiff University) , Magdalena Lipka-Lloyd (Cardiff University) , Rebecca C. Trueman (University of Nottingham) , Benjamin D. Bax (Cardiff University) , Youcef Mehellou (Cardiff University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Chembiochem

State: Published (Approved)
Published: November 2021
Diamond Proposal Number(s): 20147

Abstract: STE20/SPS1-related proline/alanine-rich kinase (SPAK) and Oxidative Stress Responsive 1 (OSR1) kinase are two serine/threonine protein kinases that regulate the function of ion co-transporters through phosphorylation. The highly conserved C -terminal (CCT) domains of SPAK and OSR1 bind to RFx[V/I] peptide sequences from their upstream With No Lysine Kinases (WNKs), facilitating their activation via phosphorylation. Thus, the inhibition of SPAK and OSR1 binding, via their CCT domains, to WNK kinases is a plausible strategy for inhibiting SPAK and OSR1 kinases. To facilitate structure-guided drug design of such inhibitors, we expressed and purified human SPAK and OSR1 CCT domains and solved their crystal structures. Interestingly, these crystal structures show a highly conserved primary pocket adjacent to a flexible secondary pocket. We also employed a biophysical strategy and determined the affinity of SPAK and OSR1 CCT domains to short peptides derived from WNK4 and NKCC1. Together, this work provides a platform that facilitates the design of CCT domain specific small molecule binders that inhibit SPAK- and OSR1-activation by WNK kinases, and these could be useful in treating hypertension and ischemic stroke.

Journal Keywords: SPAK; OSR1; Kinase; Crystal structure; Inhibitor

Diamond Keywords: Cardiovascular Disease

Subject Areas: Biology and Bio-materials, Chemistry, Medicine


Instruments: I03-Macromolecular Crystallography

Added On: 03/11/2021 09:06

Discipline Tags:

Non-Communicable Diseases Health & Wellbeing Biochemistry Chemistry Structural biology Biophysics Drug Discovery Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)