Non-degradative ubiquitination of the Notch1 receptor by the E3 ligase MDM2 activates the Notch signalling pathway

2013 ◽  
Vol 450 (3) ◽  
pp. 523-536 ◽  
Author(s):  
Susanne Pettersson ◽  
Matylda Sczaniecka ◽  
Lorna McLaren ◽  
Fiona Russell ◽  
Karen Gladstone ◽  
...  

The Notch receptor is necessary for modulating cell fate decisions throughout development, and aberrant activation of Notch signalling has been associated with many diseases, including tumorigenesis. The E3 ligase MDM2 (murine double minute 2) plays a role in regulating the Notch signalling pathway through its interaction with NUMB. In the present study we report that MDM2 can also exert its oncogenic effects on the Notch signalling pathway by directly interacting with the Notch 1 receptor through dual-site binding. This involves both the N-terminal and acidic domains of MDM2 and the RAM [RBP-Jκ (recombination signal-binding protein 1 for Jκ)-associated molecule] and ANK (ankyrin) domains of Notch 1. Although the interaction between Notch1 and MDM2 results in ubiquitination of Notch1, this does not result in degradation of Notch1, but instead leads to activation of the intracellular domain of Notch1. Furthermore, MDM2 can synergize with Notch1 to inhibit apoptosis and promote proliferation. This highlights yet another target for MDM2-mediated ubiquitination that results in activation of the protein rather than degradation and makes MDM2 an attractive target for drug discovery for both the p53 and Notch signalling pathways.

Development ◽  
1997 ◽  
Vol 124 (6) ◽  
pp. 1139-1148 ◽  
Author(s):  
J.L. Pompa de la ◽  
A. Wakeham ◽  
K.M. Correia ◽  
E. Samper ◽  
S. Brown ◽  
...  

The Notch pathway functions in multiple cell fate determination processes in invertebrate embryos, including the decision between the neuroblast and epidermoblast lineages in Drosophila. In the mouse, targeted mutation of the Notch pathway genes Notch1 and RBP-Jk has demonstrated a role for these genes in somite segmentation, but a function in neurogenesis and in cell fate decisions has not been shown. Here we show that these mutations lead to altered expression of the Notch signalling pathway homologues Hes-5, Mash-1 and Dll1, resulting in enhanced neurogenesis. Precocious neuronal differentiation is indicated by the expanded expression domains of Math4A, neuroD and NSCL-1. The RBP-Jk mutation has stronger effects on expression of these genes than does the Notch1 mutation, consistent with functional redundancy of Notch genes in neurogenesis. Our results demonstrate conservation of the Notch pathway and its regulatory mechanisms from fly to mouse, and support a role for the murine Notch signalling pathway in the regulation of neural stem cell differentiation.


2016 ◽  
Vol 28 (11) ◽  
pp. 1663 ◽  
Author(s):  
D. Murta ◽  
M. Batista ◽  
A. Trindade ◽  
E. Silva ◽  
L. Mateus ◽  
...  

The oviduct and uterus undergo extensive cellular remodelling during the oestrous cycle, requiring finely tuned intercellular communication. Notch is an evolutionarily conserved cell signalling pathway implicated in cell fate decisions in several tissues. In the present study we evaluated the quantitative real-time polymerase chain reaction (real-time qPCR) and expression (immunohistochemistry) patterns of Notch components (Notch1–4, Delta-like 1 (Dll1), Delta-like 4 (Dll4), Jagged1–2) and effector (hairy/enhancer of split (Hes) 1–2, Hes5 and Notch-Regulated Ankyrin Repeat-Containing Protein (Nrarp)) genes in the mouse oviduct and uterus throughout the oestrous cycle. Notch genes are differentially transcribed and expressed in the mouse oviduct and uterus throughout the oestrous cycle. The correlated transcription levels of Notch components and effector genes, and the nuclear detection of Notch effector proteins, indicate that Notch signalling is active. The correlation between transcription levels of Notch genes and progesterone concentrations, and the association between expression of Notch proteins and progesterone receptor (PR) activation, indicate direct progesterone regulation of Notch signalling. The expression patterns of Notch proteins are spatially and temporally specific, resulting in unique expression combinations of Notch receptor, ligand and effector genes in the oviduct luminal epithelium, uterus luminal and glandular epithelia and uterine stroma throughout the oestrous cycle. Together, the results of the present study imply a regulatory role for Notch signalling in oviduct and uterine cellular remodelling occurring throughout the oestrous cycle.


Development ◽  
1994 ◽  
Vol 120 (12) ◽  
pp. 3537-3548 ◽  
Author(s):  
B. Jennings ◽  
A. Preiss ◽  
C. Delidakis ◽  
S. Bray

The Enhancer of split locus is required during many cell-fate decisions in Drosophila, including the segregation of neural precursors in the embryo. We have generated monoclonal antibodies that recognise some of the basic helix-loop-helix proteins encoded by the Enhancer of split locus and have used them to examine expression of Enhancer of split proteins during neurogenesis. The proteins are expressed in a dynamic pattern in the ventral neurogenic region and are confined to those ectodermal cells that surround a neuroblast in the process of delaminating. There is no staining in the neuroblasts themselves. We have also examined the relationship between Enhancer of split protein accumulation and the Notch signalling pathway. Protein expression is abolished in a number of neurogenic mutant backgrounds, including Notch, but is increased as a result of expressing a constitutively active Notch product. We conclude that Notch signalling activity is directly responsible for the accumulation of basic helix-loop-helix proteins encoded by the Enhancer of split locus.


Author(s):  
Abigail Edwards ◽  
Keith Brennan

The Notch signalling pathway is a highly conserved developmental signalling pathway, with vital roles in determining cell fate during embryonic development and tissue homeostasis. Aberrant Notch signalling has been implicated in many disease pathologies, including cancer. In this review, we will outline the mechanism and regulation of the Notch signalling pathway. We will also outline the role Notch signalling plays in normal mammary gland development and how Notch signalling is implicated in breast cancer tumorigenesis and progression. We will cover how Notch signalling controls several different hallmarks of cancer within epithelial cells with sections focussed on its roles in proliferation, apoptosis, invasion, and metastasis. We will provide evidence for Notch signalling in the breast cancer stem cell phenotype, which also has implications for therapy resistance and disease relapse in breast cancer patients. Finally, we will summarise the developments in therapeutic targeting of Notch signalling, and the pros and cons of this approach for the treatment of breast cancer.


Genetics ◽  
1995 ◽  
Vol 141 (4) ◽  
pp. 1491-1505
Author(s):  
D F Lyman ◽  
B Yedvobnick

Abstract The neurogenic Notch locus of Drosophila encodes a receptor necessary for cell fate decisions within equivalence groups, such as proneural clusters. Specification of alternate fates within clusters results from inhibitory communication among cells having comparable neural fate potential. Genetically, Hairless (H) acts as an antagonist of most neurogenic genes and may insulate neural precursor cells from inhibition. H function is required for commitment to the bristle sensory organ precursor (SOP) cell fate and for daughter cell fates. Using Notch gain-of-function alleles and conditional expression of an activated Notch transgene, we show that enhanced signaling produces H-like loss-of-function phenotypes by suppressing bristle SOP cell specification or by causing an H-like transformation of sensillum daughter cell fates. Furthermore, adults carrying Notch gain of function and H alleles exhibit synergistic enhancement of mutant phenotypes. Over-expression of an H+ transgene product suppressed virtually all phenotypes generated by Notch gain-of-function genotypes. Phenotypes resulting from over-expression of the H+ transgene were blocked by the Notch gain-of-function products, indicating a balance between Notch and H activity. The results suggest that H insulates SOP cells from inhibition and indicate that H activity is suppressed by Notch signaling.


Genetics ◽  
1996 ◽  
Vol 144 (3) ◽  
pp. 1127-1141 ◽  
Author(s):  
Esther M Verheyen ◽  
Karen J Purcell ◽  
Mark E Fortini ◽  
Spyros Artavanis-Tsakonas

Abstract The Notch receptor controls cell fate decisions throughout Drosophila development. Truncated, ligand-independent forms of this protein delay or block differentiation. We have previously shown that expression of the intracellular domain of the receptor under the control of the sevenless enhancer/promoter induces a rough eye phenotype in the adult fly. Analysis of the resultant cellular transformations suggested that this form of Notch acts as a constitutively activated receptor. To identify gene products that interact with Notch, a second-site mutagenesis screen was performed to isolate enhancers and suppressors of the eye phenotype caused by expression of these activated Notch molecules. We screened 137,000 mutagenized flies and recovered 290 dominant modifiers. Many new alleles of previously identified genes were isolated, as were mutations defining novel loci that may function in the Notch signaling pathway. We discuss the data with respect to known features of Notch receptor signaling and Drosophila eye development.


2021 ◽  
Author(s):  
Marlena Brzozowa-Zasada

Summary Background It is generally accepted that angiogenesis is a complex and tightly regulated process characterized by the growth of blood vessels from existing vasculature. Activation of the Notch signalling pathway affects multiple aspects of vascular development. One of the components of the Notch signalling pathway, Delta-like ligand 4 (DLL4), has recently appeared as a critical regulator of tumour angiogenesis and thus as a promising therapeutic target. Methods This review article includes available data from peer-reviewed publications associated with the role of DLL4 in cancer angiogenesis. Searches were performed in PubMed, EMBASE, Google Scholar and Web of Science using the terms “tumour angiogenesis”, “DLL4”, “Notch signalling” and “anti-cancer therapy”. Results The survival curves of cancer patients revealed that the patients with high DLL4 expression levels had significantly shorter survival times than the patients with low DLL4 expression. Moreover, a positive correlation was also identified between DLL4 and VEGF receptorsʼ expression levels. It seems that inhibition of DLL4 may exert potent growth inhibitory effects on some tumours resistant to anti-VEGF therapies. A great number of blocking agents of DLL4/Notch signalling including anti-DLL4 antibodies, DNA vaccination, Notch antibodies and gamma-secretase inhibitors have been studied in preclinical tumour models. Conclusion DLL4 seems to be a promising target in anti-cancer therapy. Nevertheless, the careful evaluation of adverse effects on normal physiological processes in relation to therapeutic doses of anti-DLL4 drugs will be significant for advancement of DLL4 blocking agents in clinical oncology.


2007 ◽  
Vol 306 (1) ◽  
pp. 301
Author(s):  
Hugo J. Bellen ◽  
Melih Acar ◽  
Hamed Jafar Nejad ◽  
Anchi Tien ◽  
Akhila Rajan

Development ◽  
1995 ◽  
Vol 121 (11) ◽  
pp. 3745-3752 ◽  
Author(s):  
V. Jennings ◽  
J. de Celis ◽  
C. Delidakis ◽  
A. Preiss ◽  
S. Bray

The proteins encoded by Notch and the Enhancer of split complex are components of a cell-cell interaction mechanism which is important in many cell fate decisions throughout development. One such decision is the formation of the sensory organ precursor cell during the development of the peripheral nervous system in Drosophila. Cells acquire the potential to be neural through the expression of the proneural genes, and the Notch pathway is required to limit neural fate to a single cell from a proneural cluster. However, despite extensive analysis, the precise pathways linking the proneural with Notch and Enhancer of split gene functions remain obscure. For example, it has been suggested that achaete-scute complex proteins directly activate Enhancer of split genes leaving the action of Notch in the pathway unclear. Using monoclonal antibodies that recognise products of the Enhancer of split complex, we show that these proteins accumulate in the cells surrounding the developing sensory organ precursor cell and that their expression is dependent on the activity of Notch and does not directly correlate with expression of Achaete. We further clarify the pathway by showing that ubiquitous expression of an activated Notch receptor leads to widespread accumulation of Enhancer of split proteins even in the absence of achaete-scute complex proteins. Thus Enhancer of split protein expression in response to Notch activity does not require achaete-scute complex proteins.


Sign in / Sign up

Export Citation Format

Share Document