The genetic ablation of SRC-3 protects against obesity and improves insulin sensitivity by reducing the acetylation of PGC-1a
Por:
Coste A, Louet JF, Lagouge M, Lerin C, Antal MC, Meziane H, Schoonjans K, Puigserver P, O'Malley BW and Auwerx J
Publicada:
4 nov 2008
Categoría:
Multidisciplinary
Resumen:
Transcriptional control of metabolic circuits requires coordination between specific transcription factors and coregulators and is often deregulated in metabolic diseases. We characterized here the mechanisms through which the coactivator SRC-3 controls energy homeostasis. SRC-3 knock-out mice present a more favorable metabolic profile relative to their wild-type littermates. This metabolic improvement in SRC-3(-/-) mice is caused by an increase in mitochondrial function and in energy expenditure as a consequence of activation of PGC-1 alpha. By controlling the expression of the only characterized PGC-1 alpha acetyltransf erase GCN5, SRC-3 induces PGC-1 alpha acetylation and consequently inhibits its activity. Interestingly, SRC-3 expression is induced by caloric excess, resulting in the inhibition of PGC-1 alpha activity and energy expenditure, whereas caloric restriction reduces SRC-3 levels leading to enhanced PGC-1 alpha activity and energy expenditure. Collectively, these data suggest that SRC-3 is a critical link in a cofactor network that uses PGC-1 alpha as an effector to control mitochondrial function and energy homeostasis.
Green Submitted
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