l-Asparaginase regulates mTORC1 activity via a TSC2-dependent pathway in pancreatic beta cells.
Biochem Biophys Res Commun
; 652: 121-130, 2023 04 16.
Article
em En
| MEDLINE
| ID: mdl-36842323
ABSTRACT
Eif2ak4, a susceptibility gene for type 2 diabetes, encodes GCN2, a molecule activated by amino acid deficiency. Mutations or deletions in GCN2 in pancreatic ß-cells increase mTORC1 activity by decreasing Sestrin2 expression in a TSC2-independent manner. In this study, we searched for molecules downstream of GCN2 that suppress mTORC1 activity in a TSC2-dependent manner. To do so, we used a pull-down assay to identify molecules that competitively inhibit the binding of the T1462 phosphorylation site of TSC2 to 14-3-3. l-asparaginase was identified. Although l-asparaginase is frequently used as an anticancer drug for acute lymphoblastic leukemia, little is known about endogenous l-asparaginase. l-Asparaginase, which is expressed downstream of GCN2, was found to bind 14-3-3 and thereby to inhibit its binding to the T1462 phosphorylation site of TSC2 and contribute to TSC2 activation and mTORC1 inactivation upon TSC2 dephosphorylation. Further investigation of the regulation of mTORC1 activity in pancreatic ß-cells by l-asparaginase should help to elucidate the mechanism of diabetes and insulin secretion failure during anticancer drug use.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Diabetes Mellitus Tipo 2
/
Células Secretoras de Insulina
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Antineoplásicos
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article