scholarly journals Oligomerization-driven MLKL ubiquitylation antagonises necroptosis

2021 ◽  
Author(s):  
Zikou Liu ◽  
Laura Francesca Dagley ◽  
Kristy Lynn Shield-Artin ◽  
Samuel Nicholas Young ◽  
Aleksandra Bankovacki ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Protein Kinase ◽  
Kinase Domain ◽  
Membrane Disruption ◽  
Fusion Strategy ◽  
Mixed Lineage Kinase ◽  
Independent Form ◽  
Lysine Residues ◽  
Kinetic Regulation

Mixed lineage kinase domain-like (MLKL) is the executioner in the caspase-independent form of programmed cell death called necroptosis. Receptor Interacting serine/threonine Protein Kinase 3 (RIPK3) phosphorylates MLKL, triggering MLKL oligomerization, membrane translocation and membrane disruption. MLKL also undergoes ubiquitylation during necroptosis, yet neither the mechanism nor significance of this event have been demonstrated. Here we show that necroptosis-specific, multi-mono-ubiquitylation of MLKL occurs following its activation and oligomerization. Ubiquitylated MLKL accumulates in a digitonin insoluble cell fraction comprising plasma/organellar membranes and protein aggregates. This ubiquitylated form is diminished by a plasma membrane located deubiquitylating enzyme. MLKL is ubiquitylated on at least 4 separate lysine residues once oligomerized, and this correlates with proteasome- and lysosome- dependent turnover. Using a MLKL-DUB fusion strategy, we show that constitutive removal of ubiquitin from MLKL licenses MLKL auto-activity independent of necroptosis signalling in mouse and human cells. Therefore, besides its role in the kinetic regulation of MLKL-induced death following an exogenous necroptotic stimulus, ubiquitylation also contributes to the restraint of basal levels of activated MLKL to avoid errant cell death.

scholarly journals Translocation of mixed lineage kinase domain-like protein to plasma membrane leads to necrotic cell death

Cell Research ◽  
2013 ◽  
Vol 24 (1) ◽  
pp. 105-121 ◽  
Author(s):  
Xin Chen ◽  
Wenjuan Li ◽  
Junming Ren ◽  
Deli Huang ◽  
Wan-ting He ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Kinase Domain ◽  
Necrotic Cell Death ◽  
Necrotic Cell ◽  
Mixed Lineage Kinase

scholarly journals Site-specific ubiquitination of MLKL targets it to endosomes and targets Listeria and Yersinia to the lysosomes

2022 ◽  
Author(s):  
Seongmin Yoon ◽  
Konstantin Bogdanov ◽  
David Wallach
Keyword(s):  
Cell Death ◽  
Defense Mechanisms ◽  
Kinase Domain ◽  
Intracellular Bacteria ◽  
Endosomal Trafficking ◽  
Polyubiquitin Chains ◽  
Mixed Lineage Kinase ◽  
Lysine Residues ◽  
Covalent Modifications ◽  
Bacterial Yield

AbstractPhosphorylation of the pseudokinase mixed lineage kinase domain-like protein (MLKL) by the protein kinase RIPK3 targets MLKL to the cell membrane, where it triggers necroptotic cell death. We report that conjugation of K63-linked polyubiquitin chains to distinct lysine residues in the N-terminal HeLo domain of phosphorylated MLKL (facilitated by the ubiquitin ligase ITCH that binds MLKL via a WW domain) targets MLKL instead to endosomes. This results in the release of phosphorylated MLKL within extracellular vesicles. It also prompts enhanced endosomal trafficking of intracellular bacteria such as Listeria monocytogenes and Yersinia enterocolitica to the lysosomes, resulting in decreased bacterial yield. Thus, MLKL can be directed by specific covalent modifications to differing subcellular sites, whence it signals either for cell death or for non-deadly defense mechanisms.

scholarly journals Uncovering human mixed lineage kinase domain-like activation in necroptosis

2019 ◽  
Vol 11 (21) ◽  
pp. 2831-2844
Author(s):  
Cristina D Guibao ◽  
Katherine Petrinjak ◽  
Tudor Moldoveanu
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase ◽  
Recent Progress ◽  
Inositol Phosphate ◽  
Kinase Domain ◽  
Structural Studies ◽  
Interacting Protein ◽  
Mixed Lineage Kinase ◽  
Membrane Rupture ◽  
Essential Components

MLKL and its obligate upstream receptor interacting protein kinase 3 are essential components of necroptosis. It is well established that MLKL is the executioner of plasma membrane rupture in necroptosis. In healthy cells MLKL is dormant. Several dormant configurations have emerged from high-resolution structural studies revealing distinct mechanisms of MLKL autoinhibition in mammals. MLKL is activated through the concerted actions of receptor interacting protein kinase 3, which phosphorylates MLKL, and, in the case of the human pathway, inositol phosphate (IP) metabolites synthesized by the IP kinases of the IP metabolic pathway. Here, we highlight recent progress toward understanding the mechanisms of regulation of human MLKL, and survey the latest opportunities for targeting MLKL in pathophysiology.

scholarly journals Lipid-dependent Akt-ivity: where, when, and how

2019 ◽  
Vol 47 (3) ◽  
pp. 897-908 ◽  
Author(s):  
Katharina M. Siess ◽  
Thomas A. Leonard
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase ◽  
Kinase Domain ◽  
Target Of Rapamycin ◽  
Endomembrane System ◽  
Essential Protein ◽  
Mechanistic Target Of Rapamycin ◽  
Subcellular Compartments ◽  
Membrane Bound ◽  
Phosphoinositide 3 Kinase

Abstract Akt is an essential protein kinase activated downstream of phosphoinositide 3-kinase and frequently hyperactivated in cancer. Canonically, Akt is activated by phosphoinositide-dependent kinase 1 and mechanistic target of rapamycin complex 2, which phosphorylate it on two regulatory residues in its kinase domain upon targeting of Akt to the plasma membrane by PI(3,4,5)P3. Recent evidence, however, has shown that, in addition to phosphorylation, Akt activity is allosterically coupled to the engagement of PI(3,4,5)P3 or PI(3,4)P2 in cellular membranes. Furthermore, the active membrane-bound conformation of Akt is protected from dephosphorylation, and Akt inactivation by phosphatases is rate-limited by its dissociation. Thus, Akt activity is restricted to membranes containing either PI(3,4,5)P3 or PI(3,4)P2. While PI(3,4,5)P3 has long been associated with signaling at the plasma membrane, PI(3,4)P2 is gaining increasing traction as a signaling lipid and has been implicated in controlling Akt activity throughout the endomembrane system. This has clear implications for the phosphorylation of both freely diffusible substrates and those localized to discrete subcellular compartments.

scholarly journals Current translational potential and underlying molecular mechanisms of necroptosis

2019 ◽  
Vol 10 (11) ◽  
Author(s):  
Tamás Molnár ◽  
Anett Mázló ◽  
Vera Tslaf ◽  
Attila Gábor Szöllősi ◽  
Gabriella Emri ◽  
...  
Keyword(s):  
Cell Death ◽  
Protein Kinase ◽  
Posttranslational Modifications ◽  
Molecular Mechanisms ◽  
Inflammatory Diseases ◽  
Immune Surveillance ◽  
Kinase Domain ◽  
Tumor Formation

Abstract Cell death has a fundamental impact on the evolution of degenerative disorders, autoimmune processes, inflammatory diseases, tumor formation and immune surveillance. Over the past couple of decades extensive studies have uncovered novel cell death pathways, which are independent of apoptosis. Among these is necroptosis, a tightly regulated, inflammatory form of cell death. Necroptosis contribute to the pathogenesis of many diseases and in this review, we will focus exclusively on necroptosis in humans. Necroptosis is considered a backup mechanism of apoptosis, but the in vivo appearance of necroptosis indicates that both caspase-mediated and caspase-independent mechanisms control necroptosis. Necroptosis is regulated on multiple levels, from the transcription, to the stability and posttranslational modifications of the necrosome components, to the availability of molecular interaction partners and the localization of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), receptor-interacting serine/threonine-protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Accordingly, we classified the role of more than seventy molecules in necroptotic signaling based on consistent in vitro or in vivo evidence to understand the molecular background of necroptosis and to find opportunities where regulating the intensity and the modality of cell death could be exploited in clinical interventions. Necroptosis specific inhibitors are under development, but >20 drugs, already used in the treatment of various diseases, have the potential to regulate necroptosis. By listing necroptosis-modulated human diseases and cataloging the currently available drug-repertoire to modify necroptosis intensity, we hope to kick-start approaches with immediate translational potential. We also indicate where necroptosis regulating capacity should be considered in the current applications of these drugs.

scholarly journals Partners in Crime: The Interplay of Proteins and Membranes in Regulated Necrosis

2020 ◽  
Vol 21 (7) ◽  
pp. 2412 ◽  
Author(s):  
Uris Ros ◽  
Lohans Pedrera ◽  
Ana J. Garcia-Saez
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Membrane Damage ◽  
Kinase Domain ◽  
Membrane Permeabilization ◽  
Plasma Membrane Damage ◽  
Intracellular Content ◽  
Regulated Necrosis ◽  
Inflammatory Phenotype ◽  
Cellular Components

Pyroptosis, necroptosis, and ferroptosis are well-characterized forms of regulated necrosis that have been associated with human diseases. During regulated necrosis, plasma membrane damage facilitates the movement of ions and molecules across the bilayer, which finally leads to cell lysis and release of intracellular content. Therefore, these types of cell death have an inflammatory phenotype. Each type of regulated necrosis is mediated by a defined machinery comprising protein and lipid molecules. Here, we discuss how the interaction and reshaping of these cellular components are essential and distinctive processes during pyroptosis, necroptosis, and ferroptosis. We point out that although the plasma membrane is the common target in regulated necrosis, different mechanisms of permeabilization have emerged depending on the cell death form. Pore formation by gasdermins (GSDMs) is a hallmark of pyroptosis, while mixed lineage kinase domain-like (MLKL) protein facilitates membrane permeabilization in necroptosis, and phospholipid peroxidation leads to membrane damage in ferroptosis. This diverse repertoire of mechanisms leading to membrane permeabilization contributes to define the specific inflammatory and immunological outcome of each type of regulated necrosis. Current efforts are focused on new therapies that target critical protein and lipid molecules on these pathways to fight human pathologies associated with inflammation.

scholarly journals Analysis of the N-terminal region of human MLKL, as well as two distinct MLKL isoforms, reveals new insights into necroptotic cell death

2016 ◽  
Vol 36 (1) ◽  
Author(s):  
Katja Hrovat Arnež ◽  
Michaela Kindlova ◽  
Nilesh J. Bokil ◽  
James M. Murphy ◽  
Matthew J. Sweet ◽  
...  
Keyword(s):  
Cell Death ◽  
Human Monocyte ◽  
Kinase Domain ◽  
Terminal Region ◽  
Activation Loop ◽  
Phosphorylation Sites ◽  
Mixed Lineage Kinase

We show that mixed lineage kinase domain-like (MLKL) isoform 2, which lacks the pseudokinase domain and activation loop phosphorylation sites, is a more potent activator of cell death compared with MLKL isoform 1. Both MLKL isoforms are expressed in human monocyte-derived macrophages.

scholarly journals Diverse Sequence Determinants Control Human and Mouse Receptor Interacting Protein 3 (RIP3) and Mixed Lineage Kinase domain-Like (MLKL) Interaction in Necroptotic Signaling

2013 ◽  
Vol 288 (23) ◽  
pp. 16247-16261 ◽  
Author(s):  
Wanze Chen ◽  
Zhenru Zhou ◽  
Lisheng Li ◽  
Chuan-Qi Zhong ◽  
Xinru Zheng ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Kinase Domain ◽  
Phosphorylation Sites ◽  
Flanking Sequence ◽  
Interacting Protein ◽  
Mixed Lineage Kinase ◽  
Signaling Complex ◽  
Evolutionarily Conserved ◽  
Mouse Cells ◽  
Human And Mouse

Receptor interacting protein 3 (RIP3) is a protein kinase essential for TNF-induced necroptosis. Phosphorylation on Ser-227 in human RIP3 (hRIP3) is required for its interaction with human mixed lineage kinase domain-like (MLKL) in the necrosome, a signaling complex induced by TNF stimulation. RIP1 and RIP3 mediate necrosome aggregation leading to the formation of amyloid-like signaling complexes. We found that TNF induces Thr-231 and Ser-232 phosphorylation in mouse RIP3 (mRIP3) and this phosphorylation is required for mRIP3 to interact with mMLKL. Ser-232 in mRIP3 corresponds to Ser-227 in hRIP3, whereas Thr-231 is not conserved in hRIP3. Although the RIP3-MLKL interaction is required for necroptosis in both human and mouse cells, hRIP3 does not interact with mMLKL and mRIP3 cannot bind to hMLKL. The species specificity of the RIP3-MLKL interaction is primarily determined by the sequence differences in the phosphorylation sites and the flanking sequence around the phosphorylation sites in hRIP3 and mRIP3. It appears that the RIP3-MLKL interaction has been selected as an evolutionarily conserved mechanism in mediating necroptosis signaling despite that differing structural and mechanistic bases for this interaction emerged simultaneously in different organisms. In addition, we further revealed that the interaction of RIP3 with MLKL prevented massive abnormal RIP3 aggregation, and therefore should be crucial for formation of the amyloid signaling complex of necrosomes. We also found that the interaction between RIP3 and MLKL is required for the translocation of necrosomes to mitochondria-associated membranes. Our data demonstrate the importance of the RIP3-MLKL interaction in the formation of functional necrosomes and suggest that translocation of necrosomes to mitochondria-associated membranes is essential for necroptosis signaling.

Sign in / Sign up

Export Citation Format

Share Document