Neogenin, Defined as a GD3-associated Molecule by Enzyme-mediated Activation of Radical Sources, Confers Malignant Properties via Intracytoplasmic Domain in Melanoma Cells.
J Biol Chem
; 291(32): 16630-43, 2016 08 05.
Article
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| MEDLINE
| ID: mdl-27288875
ABSTRACT
To investigate mechanisms for increased malignant properties in malignant melanomas by ganglioside GD3, enzyme-mediated activation of radical sources and subsequent mass spectrometry were performed using an anti-GD3 antibody and GD3-positive (GD3+) and GD3-negative (GD3-) melanoma cell lines. Neogenin, defined as a GD3-neighbored molecule, was largely localized in lipid/rafts in GD3+ cells. Silencing of neogenin resulted in the reduction of cell growth and invasion activity. Physical association between GD3 and neogenin was demonstrated by immunoblotting of the immunoprecipitates with anti-neogenin antibody from GD3+ cell lysates. The intracytoplasmic domain of neogenin (Ne-ICD) was detected in GD3+ cells at higher levels than in GD3- cells when cells were treated by a proteasome inhibitor but not when simultaneously treated with a γ-secretase inhibitor. Exogenous GD3 also induced increased Ne-ICD in GD3- cells. Overexpression of Ne-ICD in GD3- cells resulted in the increased cell growth and invasion activity, suggesting that Ne-ICD plays a role as a transcriptional factor to drive malignant properties of melanomas after cleavage with γ-secretase. γ-Secretase was found in lipid/rafts in GD3+ cells. Accordingly, immunocyto-staining revealed that GD3, neogenin, and γ-secretase were co-localized at the leading edge of GD3+ cells. All these results suggested that GD3 recruits γ-secretase to lipid/rafts, allowing efficient cleavage of neogenin. ChIP-sequencing was performed to identify candidates of target genes of Ne-ICD. Some of them actually showed increased expression after expression of Ne-ICD, probably exerting malignant phenotypes of melanomas under GD3 expression.
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Bases de datos:
MEDLINE
Asunto principal:
Regulación Neoplásica de la Expresión Génica
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Receptores de Superficie Celular
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Microdominios de Membrana
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Secretasas de la Proteína Precursora del Amiloide
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Gangliósidos
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Proteínas de Neoplasias
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Proteínas del Tejido Nervioso
Tipo de estudio:
Prognostic_studies
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Risk_factors_studies
Límite:
Humans
Idioma:
En
Revista:
J Biol Chem
Año:
2016
Tipo del documento:
Article