Fringe proteins modulate Notch-ligand cis and trans interactions to specify signaling states

The Notch signaling pathway consists of multiple types of receptors and ligands, whose interactions can be tuned by Fringe glycosyltransferases. A major challenge is to determine how these components control the specificity and directionality of Notch signaling in developmental contexts. Here, we analyzed same-cell (cis) Notch-ligand interactions for Notch1, Dll1, and Jag1, and their dependence on Fringe protein expression in mammalian cells. We found that Dll1 and Jag1 can cis-inhibit Notch1, and Fringe proteins modulate these interactions in a way that parallels their effects on trans interactions. Fringe similarly modulated Notch-ligand cis interactions during Drosophila development. Based on these and previously identified interactions, we show how the design of the Notch signaling pathway leads to a restricted repertoire of signaling states that promote heterotypic signaling between distinct cell types, providing insight into the design principles of the Notch signaling system, and the specific developmental process of Drosophila dorsal-ventral boundary formation.

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HIV Tat Impairs Neurogenesis through Functioning As a Notch Ligand and Activation of Notch Signaling Pathway

Journal of Neuroscience ◽

10.1523/jneurosci.1208-16.2016 ◽

2016 ◽

Vol 36 (44) ◽

pp. 11362-11373 ◽

Cited By ~ 21

Author(s):

Yan Fan ◽

Xiang Gao ◽

Jinhui Chen ◽

Ying Liu ◽

Johnny J. He

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Notch Signaling Pathway ◽

Notch Ligand ◽

Hiv Tat

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MP41-03 NOTCH SIGNALING PATHWAY AS COMMON TARGET OF ERG IN DIVERSE TUMOR CELL TYPES

The Journal of Urology ◽

10.1016/j.juro.2014.02.1220 ◽

2014 ◽

Vol 191 (4S) ◽

Author(s):

Ahmed Mohamed ◽

Lakshmi Ravindranath ◽

Shilpa Katta ◽

Shyh-Han Tan ◽

Yongmei Chen ◽

...

Keyword(s):

Tumor Cell ◽

Notch Signaling ◽

Signaling Pathway ◽

Cell Types ◽

Notch Signaling Pathway ◽

Common Target

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Mechanisms in Endocrinology: Notch signaling in skeletal health and disease

Acta Endocrinologica ◽

10.1530/eje-13-0115 ◽

2013 ◽

Vol 168 (6) ◽

pp. R95-R103 ◽

Cited By ~ 42

Author(s):

Stefano Zanotti ◽

Ernesto Canalis

Keyword(s):

Notch Signaling ◽

Cell Fate ◽

Target Genes ◽

Skeletal Development ◽

Alagille Syndrome ◽

Notch Signaling Pathway ◽

Loss Of Function ◽

Skeletal Health ◽

Notch Ligand ◽

Ligand Interactions

Notch receptors are single-pass transmembrane proteins that determine cell fate. Upon Notch ligand interactions, proteolytic cleavages release the Notch intracellular domain, which translocates to the nucleus to regulate the transcription of target genes, including Hairy enhancer of split (Hes) and Hes related to YRPW motif (Hey). Notch is critical for skeletal development and activity of skeletal cells, and dysregulation of Notch signaling is associated with human diseases affecting the skeleton. Inherited or sporadic mutations in components of the Notch signaling pathway are associated with spondylocostal dysostosis, spondylothoracic dysostosis and recessive brachydactyly, diseases characterized by skeletal patterning defects. Inactivating mutations of the Notch ligandJAG1or ofNOTCH2are associated with Alagille syndrome, and activating mutations inNOTCH2are associated with Hajdu–Cheney syndrome (HCS). Individuals affected by HCS exhibit osteolysis in distal phalanges and osteoporosis. NOTCH is activated in selected tumors, such as osteosarcoma, and in breast cancer cells that form osteolytic bone metastases. In conclusion, Notch regulates skeletal development and bone remodeling, and gain- or loss-of-function mutations of Notch signaling result in important skeletal diseases.

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A Human Protein with Sequence Similarity to DrosophilaMastermind Coordinates the Nuclear Form of Notch and a CSL Protein To Build a Transcriptional Activator Complex on Target Promoters

Molecular and Cellular Biology ◽

10.1128/mcb.21.13.4337-4346.2001 ◽

2001 ◽

Vol 21 (13) ◽

pp. 4337-4346 ◽

Cited By ~ 76

Author(s):

Motoo Kitagawa ◽

Toshinao Oyama ◽

Taichi Kawashima ◽

Barry Yedvobnick ◽

Anumeha Kumar ◽

...

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Mammalian Cells ◽

Sequence Similarity ◽

Notch Signaling Pathway ◽

Dominant Negative ◽

Intracellular Domain ◽

Human Sequence ◽

Pathway Expression ◽

Enhancer Of Split

ABSTRACT Mastermind (Mam) has been implicated as an important positive regulator of the Notch signaling pathway by genetic studies usingDrosophila melanogaster. Here we describe a biochemical mechanism of action of Mam within the Notch signaling pathway. Expression of a human sequence related to Drosophila Mam (hMam-1) in mammalian cells augments induction of Hairy Enhancer of split (HES) promoters by Notch signaling. hMam-1 stabilizes and participates in the DNA binding complex of the intracellular domain of human Notch1 and a CSL protein. Truncated versions of hMam-1 that can maintain an association with the complex behave in a dominant negative fashion and depress transactivation. Furthermore,Drosophila Mam forms a similar complex with the intracellular domain of Drosophila Notch andDrosophila CSL protein during activation of Enhancer of split, the Drosophila counterpart ofHES. These results indicate that Mam is an essential component of the transcriptional apparatus of Notch signaling.

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Cis-activation in the Notch signaling pathway

eLife ◽

10.7554/elife.37880 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 16

Author(s):

Nagarajan Nandagopal ◽

Leah A Santat ◽

Michael B Elowitz

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Single Cells ◽

Notch Pathway ◽

Cell Types ◽

Notch Signaling Pathway ◽

Activation Process ◽

Additional Mode ◽

Ligand Expression ◽

Multiple Ligand

The Notch signaling pathway consists of transmembrane ligands and receptors that can interact both within the same cell (cis) and across cell boundaries (trans). Previous work has shown that cis-interactions act to inhibit productive signaling. Here, by analyzing Notch activation in single cells while controlling cell density and ligand expression level, we show that cis-ligands can also activate Notch receptors. This cis-activation process resembles trans-activation in its ligand level dependence, susceptibility to cis-inhibition, and sensitivity to Fringe modification. Cis-activation occurred for multiple ligand-receptor pairs, in diverse cell types, and affected survival in neural stem cells. Finally, mathematical modeling shows how cis-activation could potentially expand the capabilities of Notch signaling, for example enabling ‘negative’ (repressive) signaling. These results establish cis-activation as an additional mode of signaling in the Notch pathway, and should contribute to a more complete understanding of how Notch signaling functions in developmental, physiological, and biomedical contexts.

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Two novel protein O-glucosyltransferases that modify sites distinct from POGLUT1 and affect Notch trafficking and signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1804005115 ◽

2018 ◽

Vol 115 (36) ◽

pp. E8395-E8402 ◽

Cited By ~ 25

Author(s):

Hideyuki Takeuchi ◽

Michael Schneider ◽

Daniel B. Williamson ◽

Atsuko Ito ◽

Megumi Takeuchi ◽

...

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Consensus Sequence ◽

Notch Signaling Pathway ◽

Fine Tuning ◽

In Vitro Assays ◽

Spectrometric Analysis ◽

Ligand Interactions ◽

Novel Protein

The Notch-signaling pathway is normally activated by Notch–ligand interactions. A recent structural analysis suggested that a novel O-linked hexose modification on serine 435 of the mammalian NOTCH1 core ligand-binding domain lies at the interface with its ligands. This serine occurs between conserved cysteines 3 and 4 of Epidermal Growth Factor-like (EGF) repeat 11 of NOTCH1, a site distinct from those modified by protein O-glucosyltransferase 1 (POGLUT1), suggesting that a different enzyme is responsible. Here, we identify two novel protein O-glucosyltransferases, POGLUT2 and POGLUT3 (formerly KDELC1 and KDELC2, respectively), which transfer O-glucose (O-Glc) from UDP-Glc to serine 435. Mass spectrometric analysis of NOTCH1 produced in HEK293T cells lacking POGLUT2, POGLUT3, or both genes showed that either POGLUT2 or POGLUT3 can add this novel O-Glc modification. EGF11 of NOTCH2 does not have a serine residue in the same location for this O-glucosylation, but EGF10 of NOTCH3 (homologous to EGF11 in NOTCH1 and -2) is also modified at the same position. Comparison of the sites suggests a consensus sequence for modification. In vitro assays with POGLUT2 and POGLUT3 showed that both enzymes modified only properly folded EGF repeats and displayed distinct acceptor specificities toward NOTCH1 EGF11 and NOTCH3 EGF10. Mutation of the O-Glc modification site on EGF11 (serine 435) in combination with sensitizing O-fucose mutations in EGF8 or EGF12 affected cell-surface presentation of NOTCH1 or reduced activation of NOTCH1 by Delta-like1, respectively. This study identifies a previously undescribed mechanism for fine-tuning the Notch-signaling pathway in mammals.

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Cis-activation in the Notch signaling pathway

10.1101/313171 ◽

2018 ◽

Cited By ~ 1

Author(s):

Nagarajan Nandagopal ◽

Leah A. Santat ◽

Michael B. Elowitz

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Single Cells ◽

Notch Pathway ◽

Cell Types ◽

Notch Signaling Pathway ◽

Activation Process ◽

Notch Receptors ◽

Ligand Expression ◽

Multiple Ligand

AbstractThe Notch signaling pathway consists of transmembrane ligands and receptors that can interact both within the same cell (cis) and across cell boundaries (trans). Previous work has shown that cis-interactions act to inhibit productive signaling. Here, by analyzing Notch activation in single cells while controlling cell density and ligand expression level, we show that cis-ligands can in fact activate Notch receptors. This cis-activation process resembles trans-activation in its ligand level dependence, susceptibility to cis-inhibition, and sensitivity to Fringe modification. Cis-activation occurred for multiple ligand-receptor pairs, in diverse cell types, and affected survival and differentiation in neural stem cells. Finally, mathematical modeling shows how cis-activation could potentially expand the capabilities of Notch signaling, for example enabling “negative” signaling. These results establish cis-activation as a prevalent mode of signaling in the Notch pathway, and should contribute to a more complete understanding of how Notch signaling functions in developmental, physiological, and biomedical contexts.

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