A5015690926- Metabolism, Diabetes, and Cancer
- Pancreatic function and diabetes
- PI3K/AKT/mTOR signaling in cancer
- Glycogen Storage Diseases and Myoclonus
- Platelet Disorders and Treatments
- Ubiquitin and proteasome pathways
- 14-3-3 protein interactions
- Diabetes Treatment and Management
- Wnt/β-catenin signaling in development and cancer
- Coagulation, Bradykinin, Polyphosphates, and Angioedema
- Genetics and Neurodevelopmental Disorders
- Mast cells and histamine
- Cancer-related gene regulation
- Hops Chemistry and Applications
- Lysosomal Storage Disorders Research
- Protein Kinase Regulation and GTPase Signaling
- Peptidase Inhibition and Analysis
- Growth Hormone and Insulin-like Growth Factors
- Cancer, Hypoxia, and Metabolism
- Hippo pathway signaling and YAP/TAZ
- Biochemical Acid Research Studies
- Myeloproliferative Neoplasms: Diagnosis and Treatment
- Carbohydrate Chemistry and Synthesis
- Protein Degradation and Inhibitors
- Phytochemical Studies and Bioactivities
University of Bristol
2008-2021
NHS Blood and Transplant
2021
Nestlé (Switzerland)
2012-2018
École Polytechnique Fédérale de Lausanne
2013-2015
University of Dundee
2010-2014
MRC Protein Phosphorylation and Ubiquitylation Unit
2010-2014
Medical Research Council
2012-2013
SummaryGlycogen synthase (GS), a key enzyme in glycogen synthesis, is activated by the allosteric stimulator glucose-6-phosphate (G6P) and dephosphorylation through inactivation of GS kinase-3 with insulin. The relative importance these two regulatory mechanisms controlling not established, mainly due to complex interplay between multiple phosphorylation sites effectors. Here we identify residue that plays an important role activation G6P. We generated knockin mice which wild-type muscle was...
During energy stress, AMP-activated protein kinase (AMPK) promotes glucose transport and glycolysis for ATP production, while it is thought to inhibit anabolic glycogen synthesis by suppressing the activity of synthase (GS) maintain balance in muscle. Paradoxically, chronic activation AMPK causes an increase accumulation skeletal cardiac muscles, which some cases associated with dysfunction. The aim this study was elucidate molecular mechanism muscle accumulation.We recently generated...
Glycogen synthase kinase-3 is a Ser/Thr kinase, tonically active in resting cells but inhibited by phosphorylation of an N-terminal Ser residue (Ser(21) GSK3α and Ser(9) GSK3β) response to varied external stimuli. Recent work suggests that GSK3 functions as negative regulator platelet function, how regulated platelets has not been examined detail. Here, we show early thrombin-mediated (0-30 s) was blocked PKC inhibitors largely absent from PKCα knock-out mice. In contrast, late (2-5 min)...
AMPK is a sensor of cellular energy status and promising target for drugs aimed at metabolic disorders. We have studied the selectivity mechanism recently described activator, C2, its cell-permeable prodrug, C13. C2 was potent allosteric activator α1-complexes that, like AMP, also protected against Thr172 dephosphorylation. Compared with caused only partial activation α2-complexes failed to protect them show that both effects could be fully restored by exchanging part linker between...
Protein kinase B (PKB, Akt) is a Ser/Thr involved in the regulation of cell survival, proliferation, and metabolism activated by dual phosphorylation on Thr308 activation loop Ser473 hydrophobic motif. It plays contributory role to platelet function, although little known about its regulation. In this study, we investigated mammalian target rapamycin complex (mTORC)-2 Akt using recently identified small molecule ATP competitive mTOR inhibitors PP242 Torin1. Both Torin1 blocked thrombin...
The liver responds to an increase in blood glucose levels the postprandial state by uptake of and conversion glycogen. Liver glycogen synthase (GYS2), a key enzyme synthesis, is controlled complex interplay between allosteric activator glucose-6-phosphate (G6P) reversible phosphorylation through kinase-3 glycogen-associated form protein phosphatase 1. Here, we initially performed mutagenesis analysis identified residue (Arg582) required for activation GYS2 G6P. We then used Arg582Ala knockin...
Lipid metabolism is important for health and insulin action, yet the fundamental process of regulating lipid during muscle contraction incompletely understood. Here, we show that liver kinase B1 (LKB1) muscle-specific knockout (LKB1 MKO) mice display decreased fatty acid (FA) oxidation treadmill exercise. LKB1 MKO also SIK3 activity, increased histone deacetylase 4 expression, NAD+ concentration SIRT1 expression genes involved in FA oxidation. In AMP-activated protein (AMPK)α2 KO mice,...
AMP-activated protein kinase is a master regulator of cell metabolism and an attractive drug target for cancer metabolic cardiovascular diseases. Point mutations in the regulatory γ2-subunit (encoded by Prkag2 gene) caused unique form human cardiomyopathy characterized cardiac hypertrophy, ventricular preexcitation, glycogen storage. Understanding disease mechanisms not only beneficial patients but also critical to use as target.We sought identify pro-growth-signaling pathway(s) triggered...
The elevation of [cAMP](i) is an important mechanism platelet inhibition and regulated by the opposing activity adenylyl cyclase phosphodiesterase (PDE). In this study, we demonstrate that a variety agonists, including thrombin, significantly enhance PDE3A in phosphorylation-dependent manner. Stimulation platelets with PAR-1 agonist SFLLRN resulted rapid transient phosphorylation on Ser(312), Ser(428), Ser(438), Ser(465), Ser(492), parallel PKC (protein kinase C) substrate, pleckstrin....
Significance The body stores excess blood glucose as glycogen, a sugary substance that contains up to 55,000 molecules joined together chain, mostly in liver and muscle cells. Conversion of glycogen these cells plays an important role regulating levels. Glycogen ensures we don’t run out fuel during prolonged exercise. To make from sugar, need two enzymes: glycogenin synthase. Glycogenin kick starts the process by first linking itself string residues then recruiting synthase elaborate this...
Rapamycin, an inhibitor of mammalian target rapamycin complex-1 (mTORC1), reduces platelet spreading, thrombus stability, and clot retraction. Despite important role mTORC1 in function, little is known about how it regulated. The objective this study was to determine the signaling pathways that regulate human platelets.Mammalian activation assessed by measuring phosphorylation its downstream substrate ribosomal S6 kinase 1 (p70S6K).Thrombin or protein C (PKC) activator phorbal 12-myristate...
One of the mechanisms by which PI3 kinase can regulate platelet function is through phosphorylation downstream substrates, including glycogen synthase kinase-3 (GSK3)α and GSK3β. Platelet activation results in an N-terminal serine residue GSK3α (Ser21) GSK3β (Ser9), competitively inhibits substrate phosphorylation. However, role these paralogs still largely unknown. Here, we employed GSK3α/β phosphorylation-resistant mouse models to explore this inhibitory regulating activation. Expression...
PCTAIRE-1 (cyclin-dependent kinase [CDK] 16) is a highly conserved serine/threonine that belongs to the CDK family of protein kinases. Little known regarding regulation and function no robust assay exists assess activity mainly due lack information its preferred consensus motif bona fide substrates. We used positional scanning peptide library technology identified substrate-specificity requirements subsequently elaborated substrate termed PCTAIRE-tide. Recombinant displayed vastly improved...
PCTAIRE-1 [also known as cyclin-dependent kinase 16 (CDK16)] is implicated in various physiological processes such neurite outgrowth and vesicle trafficking; however, its molecular regulation downstream targets are largely unknown. Cyclin Y has recently been identified a key interacting/activating cyclin for PCTAIRE-1; the mechanism by which it activates undefined. In present study, we initially performed protein sequence analysis two candidate phosphorylation sites (Ser12 Ser336) on that...
We report the successful expression and purification of functional human muscle glycogen synthase (GYS1) in complex with glycogenin-1 (GN1). Stoichiometric GYS1:GN1 was produced by co-expression GYS1 GN1 using a bicistronic pFastBac™-Dual vector, followed affinity subsequent size-exclusion chromatography. Mass spectrometry analysis identified that is phosphorylated at several well-characterised uncharacterised Ser/Thr residues. Biochemical analysis, including activity ratio (in absence...
mTORC2 Protein-mediated Protein Kinase B (Akt) Serine 473 Phosphorylation Is Not Required for Akt1 Activity in Human PlateletsJournal of Biological ChemistryVol. 286Issue 28PreviewProtein kinase (PKB, Akt) is a Ser/Thr involved the regulation cell survival, proliferation, and metabolism activated by dual phosphorylation on Thr308 activation loop Ser473 hydrophobic motif. It plays contributory role to platelet function, although little known about its regulation. In this study, we...
AMP-activated protein kinase (AMPK) is an energy sensor and a key regulator of cell metabolism, hence promising drug target. The cardiac functions AMPK have not been understood. Point mutations in the regulatory γ2-subunit (encoded by PRKAG2 gene) shown to cause unique form cardiomyopathy humans characterized hypertrophy, arrhythmias glycogen storage. We previously that mutation caused aberrant activation absence deficit subsequently triggered re-routing excessive glucose into pool. In this...