Publications

Marie Synakewicz, Rohan S Eapen, Albert Perez-Riba, Pamela J E Rowling, Daniela Bauer, Andreas Weißl, Gerhard Fischer, Marko Hyvönen, Matthias Rief, Laura S Itzhaki, Johannes Stigler

ACS Nano, 2022 (online before print version)
DOI: doi: 10.1021/acsnano.1c09162
Pubmed: 35258937

Abstract

Tandem-repeat proteins comprise small secondary structure motifs that stack to form one-dimensional arrays with distinctive mechanical properties that are proposed to direct their cellular functions. Here, we use single-molecule optical tweezers to study the folding of consensus-designed tetratricopeptide repeats (CTPRs), superhelical arrays of short helix-turn-helix motifs. We find that CTPRs display a spring-like mechanical response in which individual repeats undergo rapid equilibrium fluctuations between partially folded and unfolded conformations. We rationalize the force response using Ising models and dissect the folding pathway of CTPRs under mechanical load, revealing how the repeat arrays form from the center toward both termini simultaneously. Continue reading →

Callum Talbot-Cooper, Teodors Pantelejevs, John P. Shannon, Christian R. Cherry, Marcus T. Au, Marko Hyvönen, Heather D. Hickman, Geoffrey L.Smith

Cell Host & Microbe, in press.
DOI: 10.1016/j.chom.2022.01.014
Pubmed: 35182467

PDB coordinates:: 7NUF (3D view)

Abstract

The induction of interferon (IFN)-stimulated genes by STATs is a critical host defense mechanism against virus infection. Here, we report that a highly expressed poxvirus protein, 018, inhibits IFN-induced signaling by binding to the SH2 domain of STAT1, thereby preventing the association of STAT1 with an activated IFN receptor. Despite encoding other inhibitors of IFN-induced signaling, a poxvirus mutant lacking 018 was attenuated in mice. The 2.0 Å crystal structure of the 018:STAT1 complex reveals a phosphotyrosine-independent mode of 018 binding to the SH2 domain of STAT1. Moreover, the STAT1-binding motif of 018 shows similarity to the STAT1-binding proteins from Nipah virus, which, similar to 018, block the association of STAT1 with an IFN receptor. Overall, these results uncover a conserved mechanism of STAT1 antagonism that is employed independently by distinct virus families.

Laurens H. Lindenburg, Teodors Pantelejevs, Fabrice Gielen, Pedro Zuazua-Villar, Maren Butz, Eric Rees, Clemens F. Kaminski, Jessica A. Downs, Marko Hyvönen, and Florian Hollfelder

Proceedings of the National Academy of Sciences of the USA 118:e2017708118 (2021)
DOI: 10.1073/pnas.2017708118
Pubmed: 34772801
PDB coordinates: 6HQU (3D view)

Abstract

Exchanges of protein sequence modules support leaps in function unavailable through point mutations during evolution. Here we study the role of the two RAD51-interacting modules within the eight binding BRC repeats of BRCA2. We created 64 chimeric repeats by shuffling these modules and measured their binding to RAD51. We found that certain shuffled module combinations were stronger binders than any of the module combinations in the natural repeats. Surprisingly, the contribution from the two modules was poorly correlated with affinities of natural repeats, with a weak BRC8 repeat containing the most effective N-terminal module. Continue reading →

Matthew Ratcliff, Richard Xu Zhou, Lutz Jermutus and Marko Hyvönen

Biochemical Society Transactions, BST20200663 (2021)
DOI: 10.1042/BST20200663
Pubmed: 34495310

Abstract

Many growth factors and cytokines are produced as larger precursors, containing prodomains, that require proteolytic processing to release the bioactive ligand. These prodomains can be significantly larger than the mature domains and can play an active role in the regulation of the ligands. Mining the UniProt database, we identified almost one hundred human growth factors and cytokines with pro-domains. These are spread across several unrelated protein families and vary in both their size and composition. Continue reading →

Anassuya Ramachandran, Merima Mehić, Laabiah Wasim, Dessislava Malinova, Ilaria Gori, Beata K Blaszczyk, Diana M Carvalho, Eileen M Shore, Chris Jones, Marko Hyvönen, Pavel Tolar, Caroline S Hill

EMBO Journal e106317 (2021)
DOI: 10.15252/embj.2020106317
Pubmed: 34003511

Abstract

Fibrodysplasia ossificans progressiva (FOP) and diffuse intrinsic pontine glioma (DIPG) are debilitating diseases that share causal mutations in ACVR1, a TGF-β family type I receptor. ACVR1R206H is a frequent mutation in both diseases. Pathogenic signaling via the SMAD1/5 pathway is mediated by Activin A, but how the mutation triggers aberrant signaling is not known. We show that ACVR1 is essential for Activin A-mediated SMAD1/5 phosphorylation and is activated by two distinct mechanisms. Wild-type ACVR1 is activated by the Activin type I receptors, ACVR1B/C. Continue reading →

Eleanor L. Atkinson, Jessica Iegre, Paul D. Brear, Elizabeth A. Zhabina, Marko Hyvönen and David R. Spring

Molecules 26(7):1977(2021)
DOI: 10.3390/molecules26071977
Pubmed: 33807474

Abstract

Protein kinases are a large class of enzymes with numerous biological roles and many have been implicated in a vast array of diseases, including cancer and the novel coronavirus infection COVID-19. Thus, the development of chemical probes to selectively target each kinase is of great interest. Inhibition of protein kinases with ATP-competitive inhibitors has historically been the most widely used method. However, due to the highly conserved structures of ATP-sites, the identification of truly selective chemical probes is challenging. In this review, we use the Ser/Thr kinase CK2 as an example to highlight the historical challenges in effective and selective chemical probe development, alongside recent advances in the field and alternative strategies aiming to overcome these problems. Continue reading →

Jessica Iegre, Eleanor L. Atkinson, Paul D. Brear, Bethany M. Cooper, Marko Hyvönen and David R. Spring

Organic & Biomolecular Chemistry, in press, (2021)
DOI: 10.1039/D1OB00257K

Abstract

CK2 is a protein kinase that plays important roles in many physio-pathological cellular processes. As such, the development of chemical probes for CK2 has received increasing attention in the past decade with more than 40 lead compounds developed. In this review, we aim to provide the reader with a comprehensive overview of the chemical probes acting outside the highly-conserved ATP-site developed to date. Continue reading →

Duncan E. Scott, Nicola J. Francis-Newton, May E. Marsh, Anthony G. Coyne, Gerhard Fischer, Tommaso Moschetti, Andrew R. Bayly, Timothy D. Sharpe, Kalina T. Haas, Lorraine Barber, Chiara R. Valenzano, Rajavel Srinivasan, David J. Huggins, Miyoung Lee, Amy Emery, Bryn Hardwick, Matthias Ehebauer, Claudio Dagostin, Alessandro Esposito, Luca Pellegrini, Trevor Perrior, Grahame McKenzie, Tom L. Blundell, Marko Hyvönen, John Skidmore, Ashok R. Venkitaraman, Chris Abell

Cell Chemical Biology, Online now , (2021)
DOI: j.chembiol.2021.02.006
Pubmed: 33662256
PDB coordinates:
6TV3 (3D view), 6TWR (3D view), 6TW4 (3D view), 6XTW (3D view), 6TW9 (3D view)

Lay Summary

BRCA2 is a protein that helps the body fix broken DNA. It makes sure RAD51, works when the cell needs to fix broken DNA. Scientists made a new drug candidate, CAM833,  that stops BRCA2 and RAD51 from working together. It can stop cancer cells from growing, especially when used together with other chemicals.

Abstract

BRCA2 controls RAD51 recombinase during homologous DNA recombination (HDR) through eight evolutionarily conserved BRC repeats, which individually engage RAD51 via the motif Phe-x-x-Ala. Using structure-guided molecular design, templated on a monomeric thermostable chimera between human RAD51 and archaeal RadA, we identify CAM833, a 529 Da orthosteric inhibitor of RAD51:BRC with a Kd of 366 nM. The quinoline of CAM833 occupies a hotspot, the Phe-binding pocket on RAD51 and the methyl of the substituted α-methylbenzyl group occupies the Ala-binding pocket. Continue reading →

Angelos Papadopoulos, Varvara Chalmantzi, Olga Mikhaylichenko, Marko Hyvönen, Dimitris Stellas, Aditi Kanhere, John Heath, Debbie L Cunningham, Theodore Fotsis, Carol Murphy

Stem Cell Research 50:102133 (2021)
DOI: j.scr.2020.102133
Pubmed: 33383406

Abstract

Human embryonic stem cells (hESCs) are an invaluable tool in the fields of embryology and regenerative medicine. Activin A and BMP4 are well-characterised growth factors implicated in pluripotency and differentiation. In the current study, hESCs are cultured in a modified version of mTeSR1, where low concentrations of Activin A substitute for TGFβ. This culture system is further used to investigate the changes induced by BMP4 on hESCs by employing a combination of transcriptomic and phosphoproteomic approaches. Results indicate that in a pluripotent state, hESCs maintain WNT signaling under negative regulation by expressing pathway inhibitors. Continue reading →

Paul Brear, Darby Ball, Katherine Stott, Sheena D’Arcy and Marko Hyvönen

Journal of Medicinal Chemistry: 63, 21, 12786–12798 (2020)
DOI: 0.1021/acs.jmedchem.0c01173

PDB coordinates:
6YPH (3D view),6YPK (3D view),6YPJ (3D view),6YPN (3D view)

Abstract

CK2α is a ubiquitous, well-studied kinase that is a target for small-molecule inhibition, for treatment of cancers. While many different classes of ATP-competitive inhibitors have been described for CK2α, they tend to suffer from significant off-target activity and new approaches are needed. A series of inhibitors of CK2α has recently been described as allosteric, acting at a previously unidentified binding site. Given the similarity of these inhibitors to known ATP-competitive inhibitors, we have investigated these further. In our thorough structural and biophysical analyses, we have found no evidence that these inhibitors bind to the proposed allosteric site. Continue reading →