Publications

A small-molecule inhibitor of the BRCA2-RAD51 interaction modulates RAD51 assembly and potentiates DNA damage-induced cell death

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 “in press” , (2021)
DOI: j.chembiol.2021.02.006
Pubmed: 27373274
PDB coordinates:
6TV3 (3D view), 6TWR (3D view), 6TW4 (3D view), 6XTW (3D view), 6TW9 (3D view)

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 →

Posted by Marko in Publications, 0 comments

Combined transcriptomic and phosphoproteomic analysis of BMP4 signaling in human embryonic stem cells

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 →

Posted by Marko in Publications, 0 comments

Proposed allosteric inhibitors bind to the ATP site of CK2α

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 →

Posted by Marko in Publications, 0 comments

Human BDNF/TrkB Variants Impair Hippocampal Synaptogenesis and Associate With Neurobehavioural Abnormalities

Takuhiro Sonoyama, Lukas K J Stadler, Mingyan Zhu, Julia M Keogh, Elana Henning, Fuki Hisama, Peter Kirwan, Magdalena Jura, Beata K Blaszczyk, David C DeWitt, Bas Brouwers, Marko Hyvönen, Inês Barroso, Florian T Merkle, Suzanne M Appleyard, Gary A Wayman, I Sadaf Farooqi

Scientific Reports, 2020 Jun 3;10(1):9028.
DOI: 10.1038/s41598-020-65531-x
Pubmed: 32493978

Abstract

Brain-derived neurotrophic factor (BDNF) signals through its high affinity receptor Tropomyosin receptor kinase-B (TrkB) to regulate neuronal development, synapse formation and plasticity. In rodents, genetic disruption of Bdnf and TrkB leads to weight gain and a spectrum of neurobehavioural phenotypes. Here, we functionally characterised a de novo missense variant in BDNF and seven rare variants in TrkB identified in a large cohort of people with severe, childhood-onset obesity. Continue reading →

Posted by Marko in Publications, 0 comments

Secreted BMP Antagonists and Their Role in Cancer and Bone Metastases

Grace M Todd, Zhichun Gao, Marko Hyvönen, Derek P Brazil, Peter Ten Dijke

Bone 137:115455 (2020)
DOI: 10.1016/j.bone.2020.115455
Pubmed: 32473315

Abstract

Bone morphogenetic proteins (BMPs) are multifunctional secreted cytokines that act in a highly context-dependent manner. BMP action extends beyond the induction of cartilage and bone formation, to encompass pivotal roles in controlling tissue and organ homeostasis during development and adulthood. BMPs signal via plasma membrane type I and type II serine/threonine kinase receptors and intracellular SMAD transcriptional effectors. Exquisite temporospatial control of BMP/SMAD signalling and crosstalk with other cellular cues is achieved by a series of positive and negative regulators at each step in the BMP/SMAD pathway. Continue reading →

Posted by Marko in Publications, 0 comments

Demonstration of the utility of DOS-derived fragment libraries for rapid hit derivatisation in a multidirectional fashion

Sarah L. Kidd, Elaine Fowler, Till Reinhardt, Thomas Compton, Natalia Mateu, Hector Newman, Dom Bellini, Romain Talon, Joseph McLoughlin, Tobias Krojer, Anthony Aimon, Anthony Bradley, Michael Fairhead, Paul Brear, Laura Díaz-Sáez, Katherine McAuley, Hannah F. Sore, Andrew Madin, Daniel H. O’Donovan, Kilian V. M. Huber, Marko Hyvönen, Frank von Delft, Christopher G. Dowson and David R. Spring

Chemical Science 11, 10792-10801 (2020)
DOI: 10.1039/D0SC01232G

PDB coordinates: 6Y6O (3D view),6Y6N (3D view)

Abstract

Organic synthesis underpins the evolution of weak fragment hits into potent lead compounds. Deficiencies within current screening collections often result in the requirement of significant synthetic investment to enable multidirectional fragment growth, limiting the efficiency of the hit evolution process. Diversity-oriented synthesis (DOS)-derived fragment libraries are constructed in an efficient and modular fashion and thus are well-suited to address this challenge. To demonstrate the effective nature of such libraries within fragment-based drug discovery, we herein describe the screening of a 40-member DOS library against three functionally distinct biological targets using X-Ray crystallography. Continue reading →

Posted by Marko in Publications, 0 comments

Diarylethene Moiety as an Enthalpy-Entropy Switch: Photoisomerizable Stapled Peptides for Modulating p53/MDM2 Interaction

Alexander V Strizhak, Oleg Babii, Sergii Afonin, Iuliia Bakanovic, Teodors Pantelejevs, Wenshu Xu, Elaine Fowler, Rohan Eapen, Krishna Sharma, Maxim O Platonov, Vasyl V Hurmach, Laura Itzhaki, Marko Hyvönen, Anne S Ulrich, David R Spring, Igor V Komarov

Organic and Biomolecular Chemistry, 2020 May 11, Advance article in press
DOI: 10.1039/d0ob00831a
Pubmed: 32390036

PDB coordinates: 6y4q (3D view)

Abstract

Analogs of the known inhibitor (peptide pDI) of the p53/MDM2 protein-protein interaction are reported, which are stapled by linkers bearing a photoisomerizable diarylethene moiety. The corresponding photoisomers possess significantly different affinities to the p53-interacting domain of the human MDM2. Apparent dissociation constants are in the picomolar-to-low nanomolar range for those isomers with diarylethene in the “open” configuration, but up to eight times larger for the corresponding “closed” isomers. Spectroscopic, structural, and computational studies showed that the stapling linkers of the peptides contribute to their binding. Continue reading →

Posted by Marko in Publications, 0 comments

Genomic Structure and Transcript Analysis of the Rapid Alkalinization Factor (RALF) Gene Family During Host-Pathogen Crosstalk in Fragaria Vesca and Fragaria X Ananassa Strawberry

Francesca Negrini , Kevin O’Grady, Marko Hyvönen, Kevin M Folta, Elena Baraldi

PLoS One 15(3):e0226448
DOI: 10.1371/journal.pone.0226448
Pubmed: 32214345

Abstract

Rapid Alkalinization Factors (RALFs) are cysteine-rich peptides ubiquitous within plant kingdom. They play multiple roles as hormonal signals in diverse processes, including root elongation, cell growth, pollen tube development, and fertilization. Their involvement in host-pathogen crosstalk as negative regulators of immunity in Arabidopsis has also been recognized. In addition, peptides homologous to RALF are secreted by different fungal pathogens as effectors during early stages of infection. Previous studies have identified nine RALF genes in the diploid strawberry (Fragaria vesca) genome. This work describes the genomic organization of the RALF gene families in commercial octoploid strawberry (Fragaria × ananassa) and the re-annotated genome of F. vesca, and then compares findings with orthologs in Arabidopsis thaliana. Continue reading →

Posted by Marko in Publications, 0 comments

The thrombospondin module 1 domain of the matricellular protein CCN3 shows an atypical disulfide pattern and incomplete CWR layers

Emma-Ruoqi Xu, Aleix Lafita, Alex Bateman, Marko Hyvönen

Acta Crystallographica Section D Structural Biology D76:124-134 (2020)
DOI: 10.1107/S2059798319016747
Pubmed: 32038043

PDB coordinates:

6RK1 (3D view)

Abstract

The members of the CCN (Cyr61/CTGF/Nov) family are a group of matricellular regulatory proteins that are essential to a wide range of functional pathways in cell signalling. Through interacting with extracellular matrix components and growth factors via one of their four domains, the CCN proteins are involved in critical biological processes such as angiogenesis, cell proliferation, bone development, fibrogenesis and tumorigenesis. Here, the crystal structure of the thrombospondin module 1 (TSP1) domain of CCN3 (previously known as Nov) is presented, which shares a similar three-stranded fold with the thrombo­spondin type 1 repeats of thrombospondin-1 and spondin-1, but with variations in the disulfide connectivity. Continue reading →

Posted by Marko in Publications, 0 comments

A cryptic hydrophobic pocket in the polo-box domain of the polo-like kinase PLK1 regulates substrate recognition and mitotic chromosome segregation

Pooja Sharma, Robert Mahen, Maxim Rossmann, Jamie E. Stokes, Bryn Hardwick, David J. Huggins, Amy Emery, Dominique L. Kunciw, Marko Hyvönen, David R. Spring, Grahame J. McKenzie & Ashok R. Venkitaraman

Scientific Reports, 9:15930 (2019)
DOI: s41598-019-50702-2
Pubmed: tbd
PDB coordinates: 5NMM (3D view), 5NEI (3D view)

Abstract

The human polo-like kinase PLK1 coordinates mitotic chromosome segregation by phosphorylating multiple chromatin- and kinetochore-binding proteins. How PLK1 activity is directed to specific substrates via phosphopeptide recognition by its carboxyl-terminal polo-box domain (PBD) is poorly understood. Here, we combine molecular, structural and chemical biology to identify a determinant for PLK1 substrate recognition that is essential for proper chromosome segregation. We show that mutations ablating an evolutionarily conserved, Tyr-lined pocket in human PLK1 PBD trigger cellular anomalies in mitotic progression and timing. Continue reading →

Posted by Marko in Publications, 0 comments