A5083509118- Sphingolipid Metabolism and Signaling
- NF-κB Signaling Pathways
- Immune Response and Inflammation
- Protein Kinase Regulation and GTPase Signaling
- Cell death mechanisms and regulation
- Lipid Membrane Structure and Behavior
- Receptor Mechanisms and Signaling
- Inflammasome and immune disorders
- Barrier Structure and Function Studies
- Retinal Development and Disorders
- Cellular transport and secretion
- Photoreceptor and optogenetics research
- interferon and immune responses
- Pancreatic and Hepatic Oncology Research
- Epigenetics and DNA Methylation
- Immune cells in cancer
- Endoplasmic Reticulum Stress and Disease
- Immune Cell Function and Interaction
- Carbohydrate Chemistry and Synthesis
- Enzyme Structure and Function
- Protein Tyrosine Phosphatases
- Platelet Disorders and Treatments
- Monoclonal and Polyclonal Antibodies Research
- PARP inhibition in cancer therapy
- Neuroscience and Neuropharmacology Research
Novartis (Switzerland)
2014-2024
Novartis Institutes for BioMedical Research
2012-2024
Novartis (Austria)
2004-2010
King's College London
2009
Medical University of Vienna
2009
Guy's Hospital
2009
Cancer Research UK
2009
Institut de Pharmacologie Moléculaire et Cellulaire
1991-2002
MRC Protein Phosphorylation and Ubiquitylation Unit
1999
The Honourable Society of Lincoln's Inn
1994-1999
The immunomodulatory drug FTY720 is phosphorylated in vivo, and the resulting phosphate as a ligand for sphingosine-1-phosphate receptors responsible unique biological effects of compound. So far, phosphorylation by murine sphingosine kinase (SPHK) 1a had been documented. We found that, while also human SPHK1, type 2 isoform phosphorylates 30-fold more efficiently, because lower Km SPHK2. Similarly, SPHK2 was efficient than SPHK1a. Among splice variants SPHKs, an N-terminally extended even...
Spatially resolved fluorescence resonance energy transfer (FRET) measured by lifetime imaging microscopy (FLIM), provides a method for tracing the catalytic activity of fluorescently tagged proteins inside live cell cultures and enables determination functional state in fixed cells tissues. Here, dynamic marker protein kinase Cα (PKCα) activation is identified exploited. Activation PKCα detected through binding phosphorylation site–specific antibodies; consequent FRET donor fluorophore on...
Serine 657 in protein kinase C-α (PKCα) is a site of phosphorylation on expression the recombinant mammalian cells. To define function this phosphorylation, PKCα species with mutations were investigated. The alanine mutant, S657A PKCα, displayed slow phosphate accumulation pulse-chase experiments, indicating rate-limiting role initial phase phosphorylation. Consistent this, aspartic acid S657D showed an increased rate accumulation. Both and mutants to accumulate as fully phosphorylated forms...
FTY720 (fingolimod) is an oral sphingosine-1 phosphate (S1P) receptor modulator in phase III development for the treatment of multiple sclerosis. To further investigate its mode action, we analyzed gene expression central nervous system (CNS) during experimental autoimmune encephalomyelitis (EAE). downregulated inflammatory genes addition to vascular adhesion molecules. It decreased matrix metalloproteinase MMP-9 and increased counterregulator--tissue inhibitor metalloproteinase,...
Ceramide kinase (CERK) produces the bioactive lipid ceramide-1-phosphate (C1P) and is a key regulator of ceramide dihydroceramide levels. It likely that CERK C1P play role in inflammatory processes but cells involved mechanisms used remain to be clarified. In particular, impact on T-cell biology has not been studied so far. Here, we Cerk-/- mice backcrossed with DO11.10/RAG1-/- probe effect ablation activation. Levels interleukin (IL)-2, IL-4, IL-5, IL-13, tumor necrosis factor (TNF)-alpha,...
Abstract The paracaspase MALT1 plays an important role in immune receptor-driven signaling pathways leading to NF-κB activation. promotes by acting as a scaffold, recruiting downstream proteins, well proteolytic cleavage of multiple substrates. However, the relative contributions these two different activities T and B cell function are not understood. To investigate how activity contributes overall regulation, we generated protease-deficient mice (Malt1PD/PD) compared their phenotype with...
The generation of antisera specific for the priming phosphorylation sites on protein kinase Calpha (PKCalpha) has permitted analysis dephosphorylation these in relation to down-regulation protein. It was demonstrated that are subject agonist-induced dephosphorylation, consistent with inactivation Further, process is shown be blocked by a PKC inhibitor, indicating requirement catalytic activity. This corroborated showing constitutively active fragment PKCalpha able stimulate wild-type...
Phosphorylation of the region containing Thr-494, Thr-495 and Thr-497, present in catalytic domain protein kinase C alpha (PKC alpha), is a preliminary event necessary for subsequent PKC activation [Cazaubon Parker (1993) J. Biol. Chem. 268, 17559-17563]. To define essential residues this region, various combinations alanine substitutions threonine 494, 495 497 have been tested. These mutations yielded expressed polypeptides 76 80 kDa ratios that vary from 100% (wild-type kinase, active) to...
In the first step of visual transduction cascade a photoexcited rhodopsin molecule, R ret *, binds to GDP‐carrying transducin T GDP . The R*‐T interaction causes opening nucleotide site in and catalyzes GDP/GTP exchange by allowing release GDP. We have studied influences on this transitory complex occupancies retinal rhodopsin. After elimination released from bound transducin, complex, named *‐T e (ret for present, empty) remains stabilized almost indefinitely medium whose ionic composition...
Ceramide 1-phosphate (C1P) has been characterized as a sphingolipid that participates in cell signaling. Although C1P synthesis is thought to occur via phosphorylation of ceramide by kinase (CerK), the processes regulate formation and fate remain largely unknown. In this study we analyzed bone marrow-derived macrophages (BMDM) from CerK-null mice (Cerk(-/-)) found significant levels C1P, suggesting previously unrecognized pathways may also lead formation. After these experiments used an...
The formation of the CBM (CARD11-BCL10-MALT1) complex is pivotal for antigen-receptor-mediated activation transcription factor NF-κB. Signaling dependent on MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1), which not only acts as a scaffolding but also possesses proteolytic activity mediated by its caspase-like domain. It remained unclear how activates MALT1. Here, we provide biochemical and structural evidence that dimerization show mutations at dimer interface...
Protein kinase C signaling is desensitized through a combination of dephosphorylation and proteolysis in intact cells. The process analyzed here, as well its relationship to degradation. It established for protein Cα that occurs membrane compartment following activation temporally preceding significant phosphatase responsible the appears be heterotrimeric type 2A phosphatase, which shown part constitutively associated. Consistent with role this activity, okadaic acid inhibit phorbol...
Ceramide kinase (CerK) produces the bioactive lipid ceramide-1-phosphate (C1P) and appears as a key enzyme for controlling ceramide levels. In this study, we discovered characterized adamantane-1-carboxylic acid (2-benzoylamino-benzothiazol-6-yl)amide (NVP-231), potent, specific, reversible CerK inhibitor that competitively inhibits binding of to CerK. NVP-231 is active in low nanomolar range on purified well cellular abrogates phosphorylation ceramide, resulting decreased endogenous C1P...
Background and Purpose Ceramide kinase ( CerK ) catalyzes the generation of ceramide‐1‐phosphate which may regulate various cellular functions, including inflammatory reactions cell growth. Here, we studied effect a recently developed inhibitor, NVP ‐231, on cancer proliferation viability investigated role cycle regulators implicated in these responses. Experimental Approach The breast lung lines MCF ‐7 NCI ‐ H358 were treated with increasing concentrations ‐231 DNA synthesis, colony...
Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) is essential for immune responses triggered by antigen receptors but the contribution of its paracaspase activity not fully understood. Here, we studied how MALT1 proteolytic function regulates T-cell activation and fate after engagement receptor pathway. We show that MLT-827, a potent selective inhibitor, does prevent initial phase activation, in contrast to pan-protein kinase C inhibitor AEB071. However, MLT-827...
Abstract Human interleukin-1β (hIL-1β) is a pro-inflammatory cytokine involved in many diseases. While hIL-1β directed antibodies have shown clinical benefit, an orally available low-molecular weight antagonist still elusive, limiting the applications of hIL-1β-directed therapies. Here we describe discovery that blocks interaction with IL-1R1 receptor. Starting from low affinity fragment-based screening hit 1 , structure-based optimization resulted compound ( S )- 2 binds and antagonizes...
The inflammasome is a large multiprotein complex that assembles in the cell cytoplasm response to stress or pathogenic infection. Its primary function defend and promote secretion of pro-inflammatory cytokines, including IL-1β IL-18. Previous research has shown immortalized bone marrow-derived macrophages (iBMDMs) assembly dependent on deacetylase HDAC6 aggresome processing pathway (APP), cellular involved disposal misfolded proteins. Here we used BMDMs from mice which ablated impaired found...