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Extracellular vesicles are independent metabolic units with asparaginase activity.

ABSTRACT: Extracellular vesicles (EVs) are membrane particles involved in the exchange of a broad range of bioactive molecules between cells and the microenvironment. Although it has been shown that cells can traffic metabolic enzymes via EVs, much remains to be elucidated with regard to their intrinsic metabolic activity. Accordingly, herein we assessed the ability of neural stem/progenitor cell (NSC)-derived EVs to consume and produce metabolites. Our metabolomics and functional analyses both revealed that EVs harbor L-asparaginase activity, catalyzed by the enzyme asparaginase-like protein 1 (Asrgl1). Critically, we show that Asrgl1 activity is selective for asparagine and is devoid of glutaminase activity. We found that mouse and human NSC EVs traffic Asrgl1. Our results demonstrate, for the first time, that NSC EVs function as independent metabolic units that are able to modify the concentrations of critical nutrients, with the potential to affect the physiology of their microenvironment.

SUBMITTER: Iraci N

PROVIDER: S-EPMC5563455 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Extracellular vesicles are independent metabolic units with asparaginase activity.

Iraci Nunzio N Gaude Edoardo E Leonardi Tommaso T Costa Ana S H ASH Cossetti Chiara C Peruzzotti-Jametti Luca L Bernstock Joshua D JD Saini Harpreet K HK Gelati Maurizio M Vescovi Angelo Luigi AL Bastos Carlos C Faria Nuno N Occhipinti Luigi G LG Enright Anton J AJ Frezza Christian C Pluchino Stefano S

Nature chemical biology 20170703 9

Extracellular vesicles (EVs) are membrane particles involved in the exchange of a broad range of bioactive molecules between cells and the microenvironment. Although it has been shown that cells can traffic metabolic enzymes via EVs, much remains to be elucidated with regard to their intrinsic metabolic activity. Accordingly, herein we assessed the ability of neural stem/progenitor cell (NSC)-derived EVs to consume and produce metabolites. Our metabolomics and functional analyses both revealed t ...[more]

PMID: 28671681

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Extracellular vesicles are independent metabolic units with asparaginase activity.

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Extracellular vesicles are independent metabolic units with asparaginase activity.

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