scholarly journals Sweet modification and regulation of death receptor signalling pathway

Author(s):  
Kenta Moriwaki ◽  
Francis K M Chan ◽  
Eiji Miyoshi

Abstract Death receptors, members of the tumour necrosis factor receptor (TNFR) superfamily, are characterized by the presence of a death domain in the cytosolic region. TNFR1, Fas and TNF-related apoptosis-inducing ligand receptors, which are prototypical death receptors, exert pleiotropic functions in cell death, inflammation and immune surveillance. Hence, they are involved in several human diseases. The activation of death receptors and downstream intracellular signalling is regulated by various posttranslational modifications, such as phosphorylation, ubiquitination and glycosylation. Glycosylation is one of the most abundant and versatile modifications to proteins and lipids, and it plays a critical role in the development and physiology of organisms, as well as the pathology of many human diseases. Glycans control a number of cellular events, such as receptor activation, signal transduction, endocytosis, cell recognition and cell adhesion. It has been demonstrated that oligo- and monosaccharides modify death receptors and intracellular signalling proteins and regulate their functions. Here, we review the current understanding of glycan modifications of death receptor signalling and their impact on signalling activity.

2003 ◽  
Vol 39 ◽  
pp. 53-71 ◽  
Author(s):  
Harald Wajant

Death receptors [Fas/Apo-1/CD95, TNF-R1 [tumour necrosis factor (TNF) receptor 1], DR3 [death receptor 3], TRAIL-R1 [TNF-related apoptosis-inducing ligand receptor 1], TRAIL-R2, DR6, p75-NGFR [p75-nerve growth factor receptor], EDAR [ectodermal dysplasia receptor]] form a subgroup of the TNF-R superfamily that can induce apoptosis (programmed cell death) via a conserved cytoplasmic signalling module termed the death domain. Although death receptors have been recognized mainly as apoptosis inducers, there is growing evidence that these receptors also fulfil a variety of nonapoptotic functions. This review is focused on the molecular mechanisms of apoptotic and non-apoptotic death receptor signalling in light of the phenotype of mice deficient in the various death receptors.


2008 ◽  
Vol 86 (6) ◽  
pp. 521-538 ◽  
Author(s):  
Ahmed Bettaieb ◽  
Diana A. Averill-Bates

Mild temperatures such as 40 °C are physiological and occur during fevers. This study determines whether mild thermotolerance induced at 40 °C can protect HeLa cells against activation of the death receptor pathway of apoptosis by lethal hyperthermia (42–45 °C). Protein expression of heat shock proteins (Hsps) 27, 32, 60, 72, 90, and 110 was increased in thermotolerant cells (3 h, 40°C). Lethal hyperthermia (42–43 °C)  caused cell death by apoptosis, but at 45 °C there was a switch to necrosis. Mild thermotolerance protected cells against heat-induced apoptosis (Annexin V labelling). Hyperthermia induced apoptosis through generation of reactive oxygen species (ROS) and death receptor signalling. The antioxidant polyethylene glycol-catalase abrogated increased expression of Fas death ligand and caspase-8 activation in response to lethal hyperthermia (42–43 °C). Mild thermotolerance attenuated the heat induction of ROS and FasL, which were initiating events in death receptor activation and signalling. Mild thermotolerance inhibited early events in hyperthermia-induced death receptor apoptosis such as Fas-associated death domain (FADD) translocation to membranes, caspase-8 activation, and tBid translocation to mitochondria. Downstream events in apoptosis such as caspase-3 activation, cleavage of PARP and ICAD, and chromatin condensation were also diminished in thermotolerant cells. It is important to improve knowledge about adaptive responses induced by exposure to mild stresses, such as fever temperatures, which can protect cells against subsequent exposure to lethal stress.


2000 ◽  
Vol 74 (24) ◽  
pp. 11490-11494 ◽  
Author(s):  
Jürgen Brojatsch ◽  
John Naughton ◽  
Heather B. Adkins ◽  
John A. T. Young

ABSTRACT The identification of TVBS3, a cellular receptor for the cytopathic subgroups B and D of avian leukosis virus (ALV-B and ALV-D), as a tumor necrosis factor receptor-related death receptor with a cytoplasmic death domain, provides a compelling argument that viral Env-receptor interactions are linked to cell death (4). However, other TVB proteins have been described that appear to have similar death domains but are cellular receptors for the noncytopathic subgroup E of ALV (ALV-E): TVBT, a turkey subgroup E-specific ALV receptor, and TVBS1, a chicken receptor for subgroups B, D, and E ALV. To begin to understand the role of TVB receptors in the cytopathic effects associated with infection by specific ALV subgroups, we asked whether binding of a soluble ALV-E surface envelope protein (SU) to its receptor can lead to cell death. Here we report that ALV-E SU-receptor interactions can induce apoptosis in quail or turkey cells. We also show directly that TVBS1and TVBT are functional death receptors that can trigger cell death by apoptosis via a mechanism involving their cytoplasmic death domains and activation of the caspase pathway. These data demonstrate that ALV-B and ALV-E use functional death receptors to enter cells, and it remains to be determined why only subgroups B and D viral infections lead specifically to cell death.


2008 ◽  
Vol 28 (14) ◽  
pp. 4520-4535 ◽  
Author(s):  
Caitlin J. Foley ◽  
Holly Freedman ◽  
Sheryl L. Choo ◽  
Christina Onyskiw ◽  
Nai Yang Fu ◽  
...  

ABSTRACT RASSF1A is a tumor suppressor protein involved in death receptor-dependent apoptosis utilizing the Bax-interacting protein MOAP-1 (previously referred to as MAP-1). However, the dynamics of death receptor recruitment of RASSF1A and MOAP-1 are still not understood. We have now detailed recruitment to death receptors (tumor necrosis factor receptor 1 [TNF-R1] and TRAIL-R1/DR4) and identified domains of RASSF1A and MOAP-1 that are required for death receptor interaction. Upon TNF-α stimulation, the C-terminal region of MOAP-1 associated with the death domain of TNF-R1; subsequently, RASSF1A was recruited to MOAP-1/TNF-R1 complexes. Prior to recruitment to TNF-R1/MOAP-1 complexes, RASSF1A homodimerization was lost. RASSF1A associated with the TNF-R1/MOAP-1 or TRAIL-R1/MOAP-1 complex via its N-terminal cysteine-rich (C1) domain containing a potential zinc finger binding motif. Importantly, TNF-R1 association domains on both MOAP-1 and RASSF1A were essential for death receptor-dependent apoptosis. The association of RASSF1A and MOAP-1 with death receptors involves an ordered recruitment to receptor complexes to promote cell death and inhibit tumor formation.


2004 ◽  
Vol 279 (50) ◽  
pp. 52479-52486 ◽  
Author(s):  
Lance R. Thomas ◽  
Ronald L. Johnson ◽  
John C. Reed ◽  
Andrew Thorburn

Members of the tumor necrosis factor (TNF) superfamily of receptors such as Fas/CD95 and the TNF-related apoptosis-inducing ligand (TRAIL) receptors DR4 and DR5 induce apoptosis by recruiting adaptor molecules and caspases. The central adaptor molecule for these receptors is a death domain-containing protein, FADD, which binds to the activated receptor via death domain-death domain interactions. Here, we show that in addition to the death domain, the C-terminal tails of DR4 and DR5 positively regulate FADD binding, caspase activation and apoptosis. In contrast, the corresponding region in the Fas receptor has the opposite effect and inhibits binding to the receptor death domain. Replacement of wild-type or mutant DR5 molecules into DR5-deficient BJAB cells indicates that some agonistic antibodies display an absolute requirement for the C-terminal tail for FADD binding and signaling while other antibodies can function in the absence of this mechanism. These data demonstrate that regions outside the death domains of DR4 and DR5 have opposite effects to that of Fas in regulating FADD recruitment and show that different death receptor agonists can use distinct molecular mechanisms to activate signaling from the same receptor.


2004 ◽  
Vol 32 (5) ◽  
pp. 679-681 ◽  
Author(s):  
D. Scheel-Toellner ◽  
K. Wang ◽  
L.K. Assi ◽  
P.R. Webb ◽  
R.M. Craddock ◽  
...  

Neutrophils die by apoptosis spontaneously within 12–24 h of their release from the bone marrow. The mechanism regulating entry of neutrophils into apoptosis at the end of their life-span is currently under debate. Our data suggest that neutrophil apoptosis involves a novel mechanism of caspase 8 activation that is indirectly regulated by accumulation of reactive oxygen species. We detected early activation of caspase 8 upstream of caspase 3 activation, suggesting death receptor signalling. The CD95 DISC (death-inducing signalling complex) was detected in neutrophils, but blocking antibodies to death receptors did not inhibit apoptosis, suggesting a novel mechanism for caspase 8 activation. Death receptor clustering in ceramide-rich lipid rafts is thought to be an early event in their signalling, so we investigated the role of ceramide generated by ASM (acid sphingomyelinase) in neutrophil apoptosis. Ceramide was generated early in neutrophil apoptosis, and ASM activity was required for neutrophil apoptosis. Moreover, neutrophil apoptosis was significantly delayed in ASM−/− mice compared with their wild-type littermates. CD95 DISC components were present in lipid rafts in neutrophils, and were progressively clustered in cultured neutrophils. Generation of ceramide was blocked by desferrioxamine, suggesting that hydroxyl radicals are important for the activation of ASM. This observation was in line with our earlier observation of a precipitous drop in reduced glutathione in the aging neutrophil.


Blood ◽  
2006 ◽  
Vol 109 (2) ◽  
pp. 711-719 ◽  
Author(s):  
Consuelo Gajate ◽  
Faustino Mollinedo

Abstract Multiple myeloma (MM) is an incurable B-cell malignancy, requiring new therapeutic strategies. We have found that synthetic alkyl-lysophospholipids (ALPs) edelfosine and perifosine induced apoptosis in MM cell lines and patient MM cells, whereas normal B and T lymphocytes were spared. ALPs induced recruitment of Fas/CD95 death receptor, Fas-associated death domain–containing protein, and procaspase-8 into lipid rafts, leading to the formation of the death-inducing signaling complex (DISC) and apoptosis. TNF-related apoptosis-inducing ligand receptor-1/death receptor 4 (TRAIL-R1/DR4) and TRAIL-R2/DR5, as well as Bid, were also recruited into lipid rafts, linking death receptor and mitochondrial signaling pathways. ALPs induced mitochondrial cytochrome c release. Bcl-XL overexpression prevented cytochrome c release and apoptosis. A Fas/CD95-deficient MM subline expressing DR4 and DR5 was resistant to edelfosine. Fas/CD95 retrovirus transduction bestowed edelfosine sensitivity in these cells. A Fas/CD95 mutant lacking part of the intracellular domain was ineffective. Lipid raft disruption prevented ALP-induced Fas/CD95 clustering, DISC formation, and apoptosis. ALP-induced apoptosis was Fas/CD95 ligand (FasL/CD95L) independent. ALP-induced recruitment of death receptors in lipid rafts potentiated MM cell killing by FasL/CD95L and TRAIL. These data uncover a novel lipid raft–mediated therapy in MM involving concentration of death receptors in membrane rafts, with Fas/CD95 playing a major role in ALP-mediated apoptosis.


2003 ◽  
Vol 370 (1) ◽  
pp. 159-166 ◽  
Author(s):  
Ken YANAGISAWA ◽  
Kenji TAGO ◽  
Morisada HAYAKAWA ◽  
Motomichi OHKI ◽  
Hiroyuki IWAHANA ◽  
...  

Interleukin-1 (IL-1)-receptor-associated kinase (IRAK) is an indispensable signalling molecule for host-defence responses initiated by a variety of ligands that bind to members of the Toll/IL-1 receptor family. Here we report a novel splice variant of mouse IRAK-1, IRAK-1-S, which is generated by utilizing a new splicing acceptor site within exon 12. IRAK-1-S cDNA is shorter than the originally reported IRAK-1 (IRAK-1-W) cDNA by 271 nucleotides, and the subsequent frameshift causes a premature termination of translation after 23 amino acids, which are unique to the IRAK-1-S protein. To elucidate the physiological function of IRAK-1-S, we overexpressed it in 293T cells and studied the effects on the IL-1 signalling cascade. As it lacks the C-terminal region of IRAK-1-W that has been reported to contain the TRAF6 (tumour necrosis factor receptor-associated factor 6) binding domain, IRAK-1-S was unable to bind TRAF6 protein, which is a proposed downstream signalling molecule. However, IRAK-1-S overexpressed in 293T cells induced constitutive activation of nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) independent of stimulation by IL-1, as did IRAK-1-W. To clarify the mechanism of NF-κB activation by IRAK-1-S in the absence of binding to TRAF6, we demonstrated that IRAK-1-S binds to IRAK-1-W through its death domain; the findings suggested that overexpressed IRAK-1-S may bind endogenous IRAK-1-W and activate TRAF6 through IRAK-1-W. These results also indicate that this novel variant may play roles in the activation of NF-κB and JNK by IL-1 and other ligands whose signal transduction is dependent on IRAK-1 under physiological conditions.


2016 ◽  
Vol 310 (4) ◽  
pp. F284-F293 ◽  
Author(s):  
Alexis A. Gonzalez ◽  
Flavia Cifuentes-Araneda ◽  
Cristobal Ibaceta-Gonzalez ◽  
Alex Gonzalez-Vergara ◽  
Leonardo Zamora ◽  
...  

Renin is synthesized in the principal cells of the collecting duct (CD), and its production is increased via cAMP in angiotensin (ANG) II-dependent hypertension, despite suppression of juxtaglomerular (JG) renin. Vasopressin, one of the effector hormones of the renin-angiotensin system (RAS) via the type 2-receptor (V2R), activates the cAMP/PKA/cAMP response element-binding protein (CREB) pathway and aquaporin-2 expression in principal cells of the CD. Accordingly, we hypothesized that activation of V2R increases renin synthesis via PKA/CREB, independently of ANG II type 1 (AT1) receptor activation in CD cells. Desmopressin (DDAVP; 10−6 M), a selective V2R agonist, increased renin mRNA (∼3-fold), prorenin (∼1.5-fold), and renin (∼2-fold) in cell lysates and cell culture media in the M-1 CD cell line. Cotreatment with DDAVP+H89 (PKA inhibitor) or CREB short hairpin (sh) RNA prevented this response. H89 also blunted DDAVP-induced CREB phosphorylation and nuclear localization. In 48-h water-deprived (WD) mice, prorenin-renin protein levels were increased in the renal inner medulla (∼1.4- and 1.8-fold). In WD mice treated with an ACE inhibitor plus AT1 receptor blockade, renin mRNA and prorenin protein levels were still higher than controls, while renin protein content was not changed. In M-1 cells, ANG II or DDAVP increased prorenin-renin protein levels; however, there were no further increases by combined treatment. These results indicate that in the CD the activation of the V2R stimulates renin synthesis via the PKA/CREB pathway independently of RAS, suggesting a critical role for vasopressin in the regulation of renin in the CD.


Sign in / Sign up

Export Citation Format

Share Document