Professor Nick PJ Brindle

Professor of Cell Signalling  
Departments: Cardiovascular Sciences, and Molecular Cell & Biology

Tel: +44 (0)116 229 7170

Email: npjb1@le.ac.uk

Address: Henry Welcome Building, University of Leicester

Personal details

I am Professor of Cell Signalling. My first degree was from the University of Leeds and PhD from the University of Manchester. After a short period in the US, I began studying cell surface receptors during my postdoctoral work on the insulin receptor at the University of Cambridge, and a short period studying insect glutamate receptors at the Molecular Neurobiology Unit in the MRC Laboratory of Molecular Biology. Following this I held a British Heart Foundation Lectureship at Cardiff University where I started working on receptor tyrosine kinases in cardiovascular disease. At the University of Leicester, I have continued to develop my interests in the molecular mechanisms by which receptors work. In recent years I have been applying evolutionary approaches and protein engineering to understanding receptor structure, function and mechanism. As a visiting scientist at the MRC Laboratory of Molecular Biology in 2011/2012 I developed a powerful directed evolution approach for understanding and engineering receptors. This approach is providing us with fundamental insights into how receptors work, as well as helping us create new potential drugs.

Qualifications

BSc (Hons) University of Leeds

PhD University of Manchester

FHEA

Publications

Book chapters

McCarthy MJ and Brindle NPJ. (2004) Molecular Approaches to Revascularization in Peripheral Vascular Disease in Mechanisms of Vascular Disease (R Fitridge and M Thompson, eds.) Greenwich Medical Media Publishers, London.

Marron MB and Brindle NPJ. (2004) Receptor tyrsosine kinase signal transduction in the microvasculature in Encyclopaedia of the Microvasculature (D Shepro, ed,) Elsevier.

Research

• How receptors work: mechanistic, functional and structural biology of receptors
• Directed evolution for creating new proteins and understanding protein function and structure

Tie interaction shows "localization and co-localization (yellow) of the receptor tyrosine kinases Tie1 (green) and Tie2 (red) on the surface of a single live endothelial cell"

• Cardiovascular protective signalling

Highlights

Directed protein evolution by somatic hypermutation combined with cell surface display

Directed protein evolution is a powerful approach to modify protein function, create new protein functionality and probe structure-function relationships. However directed evolution of complex proteins, particularly mammalian proteins requiring post-translational modifications, is difficult. We have combined cell surface display with somatic hypermutation in B cells to perform directed evolution on a complex mammalian glycoprotein. This approach allowed us to evolve a new form of receptor ectodomain with a dramatic shift in its binding ability. The target protein in this evolution was the extracellular domain of the Tie2 receptor and we evolved this to a form showing specific binding to only one of its ligands, Ang2. We also showed the evolved ectodomain can be used as a ligand trap to block the action of Ang2, a ligand whose increased expression plays a key role in a number of diseases. We are now exploring the potential therapeutic applications of this evolved protein as well as using this approach to evolve other new protein functions.

The approach we described has great potential for engineering other complex proteins.

Brindle, N. P., Sale, J. E., Arakawa, H., Buerstedde, J. M., Nuamchit, T., Sharma, S., and Steele, K. H. (2013) Directed evolution of an Angiopoietin-2 ligand trap by somatic hypermutation and cell surface display. J. Biol. Chem. 288, 33205-33212.

Receptor interactions regulate angiopoietin signalling

The Tie family of receptor tyrosine kinases comprises of two members Tie1 and Tie2. While Tie2 is known to be a receptor for a family of ligands known as the angiopoietins, the role of Tie1 has long been a mystery. In a series of papers we showed that Tie1 physically interacts with Tie2 at the cell surface. We also found this interaction regulates the activity of Tie2 by controlling access of one of the ligands to the receptors ligand binding site. This occurs because the Tie1 extracellular domain obstructs Ang1 access to Tie2. Interestingly we found that other signals, such as VEGF and TNF-alpha, can relieve this suppression of Ang1 binding by stimulating cleavage of Tie1 ectodomain and allowing the ligand to access and activate Tie2. This receptor interaction provides an important mechanism that regulates angiopoietin signalling and enables this signalling to be co-ordinated with other signalling inputs that the cell is receiving.

Singh, H., Hansen, T. M., Patel, N., and Brindle, N. P. J. (2012) The molecular balance between receptor tyrosine kinases Tie1 and Tie2 is dynamically controlled by VEGF and TNFα and regulates angiopoietin signalling. PLoS One 7, e29319. 

Singh, H., Tahir, T. A., Alawo, D. O., Issa, E., and Brindle, N. P. (2011) Molecular control of angiopoietin signalling. Biochem. Soc. Trans. 39, 1592-1596

Hansen, T. M., Singh, H., Tahir, T. A., and Brindle, N. P. (2010) Effects of angiopoietins-1 and -2 on the receptor tyrosine kinase Tie2 are differentially regulated at the endothelial cell surface. Cell. Signal. 22, 527-532

Singh, H., Milner, C. S., Aguilar Hernandez, M. M., Patel, N., and Brindle, N. P. (2009) Vascular endothelial growth factor activates the Tie family of receptor tyrosine kinases. Cell. Signal. 21, 1346-1350

Marron, M. B., Singh, H., Tahir, T. A., Kavumkal, J., Kim, H.-Z., Koh, G. Y., and Brindle, N. P. J. (2007) Regulated proteolytic processing of Tie1 modulates ligand responsiveness of the receptor tyrosine kinase Tie2. J. Biol. Chem. 282, 30509-30517

Marron, M. B., Hughes, D. P., Edge, M. D., Forder, C. L., and Brindle, N. P. J. (2000) Evidence for heterotypic interaction between the receptor tyrosine kinases TIE-1 and TIE-2. J. Biol. Chem. 275, 39741-39746

New signalling pathways

In order to define signalling pathways by which angiopoietins regulate cellular function we use a variety of approaches including proteomics and yeast two-hybrid screens. This has led us to identify a new signalling pathway for post-transcriptional regulation of the anti-oxidant protein UCP2 by Ang1. This pathway involves the RNA-binding protein, hnRNP-K, and is important for trafficking specific mRNA species to intracellular compartments for local translation in response to ligand activation. In addition we have identified another novel signalling intermediate, A20 binding inhibitor of NFkB-2 (ABIN2), as a Tie2 binding protein. We found that following activation of cells ABIN2 is recruited from the cytoplasm to the activated receptor. ABIN2 has been shown to inhibit the inflammatory transcription factor NFkB. Suppression of ABIN2 expression blocks the ability of Ang1 to dampen NFkB activity in endothelial cells implicating ABIN2 in the anti-inflammatory and protective actions of Ang1.

Tahir, TA, Singh, H & Brindle NPJ (2014) “The RNA binding protein hnRNP-K mediates post –transcriptional regulation of Uncoupling Protein-2 by angiopoietin-1” Cell. Signal. In press DOI: 10.1016/j.cellsig.2014.03.005

Brindle, N. P. J., Saharinen, P., and Alitalo, K. (2006) Signaling and functions of Angiopoietin-1 in vascular protection. Circ. Res. 98, 1014-1023

Hughes, D. P., Marron, M. B., and Brindle, N. P. J. (2003) The antiinflammatory endothelial tyrosine kinase Tie2 interacts with a novel nuclear factor-{kappa}B inhibitor ABIN-2. Circ. Res.92, 630-636

Tadros, A., Hughes, D. P., Dunmore, B. J., and Brindle, N. P. J. (2003) ABIN-2 protects endothelial cells from death and has a role in the antiapoptotic effect of angiopoietin-1. Blood102, 4407-4409