A5005972954- Protease and Inhibitor Mechanisms
- Calpain Protease Function and Regulation
- DNA Repair Mechanisms
- Ubiquitin and proteasome pathways
- RNA modifications and cancer
- Genomics and Chromatin Dynamics
- Silk-based biomaterials and applications
- Blood Coagulation and Thrombosis Mechanisms
- Fungal and yeast genetics research
- Cancer, Hypoxia, and Metabolism
- DNA and Nucleic Acid Chemistry
- Autophagy in Disease and Therapy
- Biotin and Related Studies
- Epigenetics and DNA Methylation
- Blood properties and coagulation
- Trace Elements in Health
- Insect Resistance and Genetics
- Cell Adhesion Molecules Research
- CRISPR and Genetic Engineering
- Microtubule and mitosis dynamics
- ATP Synthase and ATPases Research
- Vector-borne infectious diseases
- Heat shock proteins research
Imperial College London
2024-2025
MRC London Institute of Medical Sciences
2025
University College London
2015-2020
Institute of Cancer Research
2017-2019
Institute of Cancer Research
2018
University of Cambridge
2013-2016
Wellcome Trust
2013-2016
Birkbeck, University of London
2016
Institute of Structural and Molecular Biology
2016
Medical Research Council
2016
Cullin-Ring E3 Ligases (CRLs) regulate a multitude of cellular pathways through specific substrate receptors. The COP9 signalosome (CSN) deactivates CRLs by removing NEDD8 from activated Cullins. Here we present structures the neddylated and deneddylated CSN-CRL2 complexes combining single-particle cryo-electron microscopy (cryo-EM) with chemical cross-linking mass spectrometry (XL-MS). These suggest conserved mechanism CSN activation, consisting conformational clamping CRL2 CSN2/CSN4,...
Abstract The eukaryotic helicase MCM2-7, is loaded by ORC, Cdc6 and Cdt1 as a double-hexamer onto replication origins. insertion of DNA into the leads to partial MCM2-7 ring closure, while ATP hydrolysis essential for consecutive steps in pre-replicative complex (pre-RC) assembly. Currently it unknown how closure ATP-hydrolysis are controlled. A cryo-EM structure an ORC-Cdc6-Cdt1-MCM2-7 intermediate shows remodelled, fully-closed Mcm2/Mcm5 interface. Mcm5 C-terminus (C5) contacts Orc3...
Abstract Human DNA licensing initiates replication fork assembly and replication. This reaction promotes the loading of hMCM2-7 complex on DNA, which represents core replicative helicase that unwinds during S-phase. Here, we report reconstitution human using purified proteins. We showed in vitro is specific results high-salt resistant double-hexamers. With ATPγS, an hORC1-5-hCDC6-hCDT1-hMCM2-7 (hOCCM) assembles independent hORC6, but hORC6 enhances double-hexamer formation. determined hOCCM...
The serpinopathies are among a diverse set of conformational diseases that involve the aberrant self-association proteins into ordered aggregates. α1-Antitrypsin deficiency is archetypal serpinopathy and results from formation deposition mutant forms α1-antitrypsin as "polymer" chains in liver tissue. No detailed structural analysis has been performed this material. Moreover, there little information on relevance well-studied artificially induced polymers to these disease-associated...
SUMMARY Human DNA licensing initiates the process of replication fork assembly. Specifically, this reaction leads to loading hMCM2-7 on DNA, which represents core replicative helicase that unwinds during S-phase. Here, we report biochemical reconstitution human using purified proteins, structural and functional analysis reveal impact cancer-associated mutations licensing. We showed in vitro is specific results assembly high-salt resistant double-hexamers, final product used ATPγS block...
The common severe Z mutation (E342K) of α1-antitrypsin forms intracellular polymers that are associated with liver cirrhosis. native fold this protein is well-established and models have been proposed from crystallographic biophysical data for the stable inter-molecular configuration terminates polymerization pathway. Despite these molecular ‘snapshots’, details transition between monomer polymer remain only partially understood. We surveyed RCL (reactive centre loop) to identify sites...
Serpins are protease inhibitors whose most stable state is achieved upon transition of a central 5-stranded β-sheet to 6-stranded form. Mutations, low pH, denaturants and elevated temperatures promote this transition, which can result in growing polymer chain inactive molecules. Different types possible, but, experimentally only heat has been shown generate polymers vitro consistent with ex vivo pathological specimens. Many mutations that alter the rate heat-induced polymerization have...
Abstract Origin recognition complex (ORC)-dependent loading of the replicative helicase MCM2-7 onto replication origins in G1-phase forms basis fork establishment S-phase. However, how ORC and facilitate genome-wide DNA licensing is not fully understood. Mapping molecular footprints budding yeast genome-wide, we discovered that associated with release from redistribution to non-origin sites. Our bioinformatic analysis revealed are compact units, where a single double hexamer blocks...
A monoclonal antibody (mAb) that binds to a transient intermediate may act as catalyst for the corresponding reaction; here we show this principle can extend on macro molecular scale induction of mutant-like oligomerization in wild-type protein. Using common pathogenic E342K (Z) variant α1-antitrypsin antigen-whose native state is susceptible formation proto-oligomeric intermediate-we have produced mAb (5E3) increases rate (M) variant. Employing ELISA, gel shift, thermal stability and FRET...
Serpins are important regulators of proteolytic pathways with an antiprotease activity that involves a conformational transition from metastable to hyperstable state. Certain mutations permit the occur in absence protease; when associated intermolecular interaction, this yields linear polymers serpin molecules, which accumulate at site synthesis. This is basis many pathologies termed serpinopathies. We have previously identified monoclonal antibody (mAb4B12) that, single-chain form, blocks...
SUMMARY Cullin-Ring E3 Ligases (CRLs) regulate a multitude of cellular pathways through specific substrate receptors. The COP9 signalosome (CSN) deactivates CRLs by removing NEDD8 (N8) from activated Cullins. structure stable CSN-CRL can be used to understand this mechanism regulation. Here we present the first structures neddylated and deneddylated CSN-CRL2 complexes combining single particle cryo-electron microscopy (cryo-EM) with chemical cross-linking mass spectrometry (MS). These reveal...