-
Structure (London, England : 1993) Apr 2023Protein kinases of the dystonia myotonica protein kinase (DMPK) family are critical regulators of actomyosin contractility in cells. The DMPK kinase MRCK1 is required...
Protein kinases of the dystonia myotonica protein kinase (DMPK) family are critical regulators of actomyosin contractility in cells. The DMPK kinase MRCK1 is required for the activation of myosin, leading to the development of cortical tension, apical constriction, and early gastrulation. Here, we present the structure, conformation, and membrane-binding properties of Caenorhabditis elegans MRCK1. MRCK1 forms a homodimer with N-terminal kinase domains, a parallel coiled coil of 55 nm, and a C-terminal tripartite module of C1, pleckstrin homology (PH), and citron homology (CNH) domains. We report the high-resolution structure of the membrane-binding C1-PH-CNH module of MRCK1 and, using high-throughput and conventional liposome-binding assays, determine its binding to specific phospholipids. We further characterize the interaction of the C-terminal CRIB motif with Cdc42. The length of the coiled-coil domain of DMPK kinases is remarkably conserved over millions of years of evolution, suggesting that they may function as molecular rulers to position kinase activity at a fixed distance from the membrane.
Topics: Animals; Protein Serine-Threonine Kinases; Myotonic Dystrophy; Myotonin-Protein Kinase; Amino Acid Sequence; Protein Kinases; Caenorhabditis elegans
PubMed: 36854301
DOI: 10.1016/j.str.2023.02.002 -
Biochimica Et Biophysica Acta.... Oct 2023Necroptosis, a cell death modality that is defined as a necrosis-like cell death depending on the receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase... (Review)
Review
Necroptosis, a cell death modality that is defined as a necrosis-like cell death depending on the receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like pseudokinase (MLKL), has been found to underlie the injury of various organs. Nevertheless, the molecular background of this cell loss seems to also involve, at least under certain circumstances, some novel axes, such as RIPK3-PGAM5-Drp1 (mitochondrial protein phosphatase 5-dynamin-related protein 1), RIPK3-CaMKII (Ca/calmodulin-dependent protein kinase II) and RIPK3-JNK-BNIP3 (c-Jun N-terminal kinase-BCL2 Interacting Protein 3). In addition, endoplasmic reticulum stress and oxidative stress via the higher production of reactive oxygen species produced by the mitochondrial enzymes and the enzymes of the plasma membrane have been implicated in necroptosis, thereby depicting an inter-organelle interplay in the mechanisms of this cell death. However, the role and relationship between these novel non-conventional signalling and the well-accepted canonical pathway in terms of tissue- and/or disease-specific prioritisation is completely unknown. In this review, we provide current knowledge on some necroptotic pathways being not directly associated with RIPK3-MLKL execution and report studies showing the role of respective microRNAs in the regulation of necroptotic injury in the heart and in some other tissues having a high expression of the pro-necroptotic proteins.
Topics: Humans; Necroptosis; Protein Kinases; Necrosis; Cell Death; Organelles
PubMed: 37399908
DOI: 10.1016/j.bbamcr.2023.119534 -
European Journal of Medicinal Chemistry Apr 2021Identifying a pharmacological agent that targets only one of more than 500 kinases present in humans is an important challenge. One potential solution to this problem is... (Review)
Review
Identifying a pharmacological agent that targets only one of more than 500 kinases present in humans is an important challenge. One potential solution to this problem is the development of bivalent kinase inhibitors, which consist of two connected fragments, each bind to a dissimilar binding site of the bisubstrate enzyme. The main advantage of bivalent (type V) kinase inhibitors is generating more interactions with target enzymes that can enhance the molecules' selectivity and affinity compared to single-site inhibitors. Earlier type V inhibitors were not suitable for the cellular environment and were mostly used in in vitro studies. However, recently developed bivalent compounds have high kinase affinity, high biological and chemical stability in vivo. This review summarized the hetero-bivalent kinase inhibitors described in the literature from 2014 to the present. We attempted to classify the molecules by serine/threonine and tyrosine kinase inhibitors, and then each target kinase and its hetero-bivalent inhibitor was assessed in depth. In addition, we discussed the analysis of advantages, limitations, and perspectives of bivalent kinase inhibitors compared with the monovalent kinase inhibitors.
Topics: Cyclic AMP-Dependent Protein Kinases; Extracellular Signal-Regulated MAP Kinases; Humans; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Receptor, EphA1; Small Molecule Libraries; TOR Serine-Threonine Kinases; src-Family Kinases
PubMed: 33730624
DOI: 10.1016/j.ejmech.2021.113318 -
Expert Opinion on Therapeutic Patents 2023The mitogen-activated protein kinase (MAPK) family consist of p38 MAP kinases, c-Jun N-terminal kinases (JNKs) and extracellular signal-regulated kinases (ERKs). They... (Review)
Review
INTRODUCTION
The mitogen-activated protein kinase (MAPK) family consist of p38 MAP kinases, c-Jun N-terminal kinases (JNKs) and extracellular signal-regulated kinases (ERKs). They are involved in a multitude of diseases, including inflammatory, autoimmune, neurodegenerative, and metabolic diseases as well as cancer. In recent years, further developments in the field of MAPK-inhibitors have been reported, including an isoform or downstream target selective inhibition of MAPKs as well as target protein degradation approaches.
AREAS COVERED
This review summarizes newly patented MAPK-inhibitors that were claimed between 2018 and early 2023. Presented are the patents as well as their corresponding publications, the storyline of development, and clinical trials involving these compounds. This article elaborates a total of 27 patents, which were identified using established search engines.
EXPERT OPINION
Although industrial research on MAPK-inhibitors has been ongoing for more than 20 years, novel clinical trials of MAPK-inhibitors as potential drug candidates are still being conducted in the period under review. Recently reported inhibitors show an excellent selectivity profile and are even achieving selectivity between closely related isoforms. This progression offers the possibility to eliminate unwanted side effects and may finally lead to the approval of the first MAPK-inhibitor.
Topics: Humans; Patents as Topic; Mitogen-Activated Protein Kinases; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Phosphorylation; p38 Mitogen-Activated Protein Kinases; Protein Kinase Inhibitors
PubMed: 37501497
DOI: 10.1080/13543776.2023.2242584 -
Biomolecules Aug 2020The family of mitogen-activated protein kinases (MAPKs) consists of fourteen members and has been implicated in regulation of virtually all cellular processes. MAPKs are... (Review)
Review
The family of mitogen-activated protein kinases (MAPKs) consists of fourteen members and has been implicated in regulation of virtually all cellular processes. MAPKs are divided into two groups, conventional and atypical MAPKs. Conventional MAPKs are further classified into four sub-families: extracellular signal-regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK1, 2 and 3), p38 (α, β, γ, δ), and extracellular signal-regulated kinase 5 (ERK5). Four kinases, extracellular signal-regulated kinase 3, 4, and 7 (ERK3, 4 and 7) as well as Nemo-like kinase (NLK) build a group of atypical MAPKs, which are activated by different upstream mechanisms than conventional MAPKs. Early studies identified JNK1/2 and ERK1/2 as well as p38α as a central mediators of inflammation-evoked insulin resistance. These kinases have been also implicated in the development of obesity and diabetes. Recently, other members of conventional MAPKs emerged as important mediators of liver, skeletal muscle, adipose tissue, and pancreatic β-cell metabolism. Moreover, latest studies indicate that atypical members of MAPK family play a central role in the regulation of adipose tissue function. In this review, we summarize early studies on conventional MAPKs as well as recent findings implicating previously ignored members of the MAPK family. Finally, we discuss the therapeutic potential of drugs targeting specific members of the MAPK family.
Topics: Animals; Humans; MAP Kinase Kinase 4; MAP Kinase Signaling System; Metabolic Diseases; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinase 7; p38 Mitogen-Activated Protein Kinases
PubMed: 32872540
DOI: 10.3390/biom10091256 -
The Journal of Biological Chemistry Apr 2023The integrated stress response (ISR) is an important mechanism by which cells confer protection against environmental stresses. Central to the ISR is a collection of...
The integrated stress response (ISR) is an important mechanism by which cells confer protection against environmental stresses. Central to the ISR is a collection of related protein kinases that monitor stress conditions, such as Gcn2 (EIF2AK4) that recognizes nutrient limitations, inducing phosphorylation of eukaryotic translation initiation factor 2 (eIF2). Gcn2 phosphorylation of eIF2 lowers bulk protein synthesis, conserving energy and nutrients, coincident with preferential translation of stress-adaptive gene transcripts, such as that encoding the Atf4 transcriptional regulator. While Gcn2 is central for cell protection to nutrient stress and its depletion in humans leads to pulmonary disorders, Gcn2 can also contribute to the progression of cancers and facilitate neurological disorders during chronic stress. Consequently, specific ATP-competitive inhibitors of Gcn2 protein kinase have been developed. In this study, we report that one such Gcn2 inhibitor, Gcn2iB, can activate Gcn2, and we probe the mechanism by which this activation occurs. Low concentrations of Gcn2iB increase Gcn2 phosphorylation of eIF2 and enhance Atf4 expression and activity. Of importance, Gcn2iB can activate Gcn2 mutants devoid of functional regulatory domains or with certain kinase domain substitutions derived from Gcn2-deficient human patients. Other ATP-competitive inhibitors can also activate Gcn2, although there are differences in their mechanisms of activation. These results provide a cautionary note about the pharmacodynamics of eIF2 kinase inhibitors in therapeutic applications. Compounds designed to be kinase inhibitors that instead directly activate Gcn2, even loss of function variants, may provide tools to alleviate deficiencies in Gcn2 and other regulators of the ISR.
Topics: Humans; Adenosine Triphosphate; Enzyme Activation; Eukaryotic Initiation Factor-2; Phosphorylation; Protein Kinase Inhibitors; Protein Kinases; Protein Serine-Threonine Kinases
PubMed: 36898579
DOI: 10.1016/j.jbc.2023.104595 -
Methods in Enzymology 2022Pseudoenzymes resemble active enzymes, but lack key catalytic residues believed to be required for activity. Many pseudoenzymes appear to be inactive in conventional...
Pseudoenzymes resemble active enzymes, but lack key catalytic residues believed to be required for activity. Many pseudoenzymes appear to be inactive in conventional enzyme assays. However, an alternative explanation for their apparent lack of activity is that pseudoenzymes are being assayed for the wrong reaction. We have discovered several new protein kinase-like families which have revealed how different binding orientations of adenosine triphosphate (ATP) and active site residue migration can generate a novel reaction from a common kinase scaffold. These results have exposed the catalytic versatility of the protein kinase fold and suggest that atypical kinases and pseudokinases should be analyzed for alternative transferase activities. In this chapter, we discuss a general approach for bioinformatically identifying divergent or atypical members of an enzyme superfamily, then present an experimental approach to characterize their catalytic activity.
Topics: Adenosine Triphosphate; Catalysis; Catalytic Domain; Humans; Protein Kinases
PubMed: 35525554
DOI: 10.1016/bs.mie.2022.03.047 -
ImmunoHorizons Jul 2022Caspase-8 (Casp8) suppresses receptor-interacting protein kinase-3 (RIPK3)/mixed lineage kinase domain-like protein (MLKL)-dependent necroptosis, demonstrated by the...
Caspase-8 (Casp8) suppresses receptor-interacting protein kinase-3 (RIPK3)/mixed lineage kinase domain-like protein (MLKL)-dependent necroptosis, demonstrated by the genetic evidence that deletion of or prevented embryonic lethality of -deficient mice. However, the detailed mechanisms by which deficiency triggers necroptosis during embryonic development remain unclear. In this article, we show that deletion caused formation of the RIPK1-RIPK3 necrosome in the yolk sac, leading to vascularization defects, prevented by MLKL and RIPK3 deficiency, or RIPK3 RHIM mutant (RIPK3 V448P), but not by the RIPK1 kinase-dead mutant (RIPK1 K45A). In addition, mice died on embryonic day 14.5, which was delayed to embryonic day 17.5 by ablation of one allele in and was completely rescued by ablation of Our results revealed an in vivo role of RIPK3 RHIM and RIPK1 scaffold-mediated necroptosis in deficiency embryonic development and suggested that the Casp8-deficient yolk sac might be implicated in identifying novel regulators as an in vivo necroptotic model.
Topics: Animals; Caspase 8; Embryonic Development; Mice; Necroptosis; Protein Kinases; Receptor-Interacting Protein Serine-Threonine Kinases
PubMed: 35858757
DOI: 10.4049/immunohorizons.2200021 -
The Enzymes 2023Discovery of the class of protein kinase now dubbed a mitogen (or messenger)-activated protein kinase (MAPK) is an illustrative example of how disparate lines of...
Discovery of the class of protein kinase now dubbed a mitogen (or messenger)-activated protein kinase (MAPK) is an illustrative example of how disparate lines of investigation can converge and reveal an enzyme family universally conserved among eukaryotes, from single-celled microbes to humans. Moreover, elucidation of the circuitry controlling MAPK function defined a now overarching principle in enzyme regulation-the concept of an activation cascade mediated by sequential phosphorylation events. Particularly ground-breaking for this field of exploration were the contributions of genetic approaches conducted using several model organisms, but especially the budding yeast Saccharomyces cerevisiae. Notably, examination of how haploid yeast cells respond to their secreted peptide mating pheromones was crucial in pinpointing genes encoding MAPKs and their upstream activators. Fully contemporaneous biochemical analysis of the activities elicited upon stimulation of mammalian cells by insulin and other growth- and differentiation-inducing factors lead eventually to the demonstration that components homologous to those in yeast were involved. Continued studies of these pathways in yeast were integral to other foundational discoveries in MAPK signaling, including the roles of tethering, scaffolding and docking interactions.
Topics: Animals; Humans; Saccharomyces cerevisiae; Mitogen-Activated Protein Kinases; Signal Transduction; Phosphorylation; Protein Kinases; Mammals
PubMed: 37945169
DOI: 10.1016/bs.enz.2023.07.001 -
Molecular Cell Jan 2024Cellular homeostasis is continuously challenged by environmental cues and cellular stress conditions. In their defense, cells need to mount appropriate stress responses... (Review)
Review
Cellular homeostasis is continuously challenged by environmental cues and cellular stress conditions. In their defense, cells need to mount appropriate stress responses that, dependent on the cellular context, signaling intensity, and duration, may have diverse outcomes. The stress- and mitogen-activated protein kinase (SAPK/MAPK) system consists of well-characterized signaling cascades that sense and transduce an array of different stress stimuli into biological responses. However, the physical and chemical nature of stress signals and how these are sensed by individual upstream MAP kinase kinase kinases (MAP3Ks) remain largely ambiguous. Here, we review the existing knowledge of how individual members of the large and diverse group of MAP3Ks sense specific stress signals through largely non-redundant mechanisms. We emphasize the large knowledge gaps in assigning function and stress signals for individual MAP3K family members and touch on the potential of targeting this class of proteins for clinical benefit.
Topics: Animals; MAP Kinase Kinase Kinases; JNK Mitogen-Activated Protein Kinases; Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Signal Transduction; Phosphorylation; p38 Mitogen-Activated Protein Kinases; Calcium-Calmodulin-Dependent Protein Kinases; Mammals
PubMed: 38118452
DOI: 10.1016/j.molcel.2023.11.028