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DAF-16/Forkhead box O transcription factor: many paths to a single Fork(head) in the road.

Program in Gene Function and Expression, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
Antioxidants & Redox Signaling (Impact Factor: 8.2). 02/2011; 14(4):623-34. DOI: 10.1089/ars.2010.3490
Source: PubMed

ABSTRACT The Caenorhabditis elegans Forkhead box O transcription factor (FOXO) homolog DAF-16 functions as a central mediator of multiple biological processes such as longevity, development, fat storage, stress resistance, and reproduction. In C. elegans, similar to other systems, DAF-16 functions as the downstream target of a conserved, well-characterized insulin/insulin-like growth factor (IGF)-1 signaling pathway. This cascade is comprised of an insulin/IGF-1 receptor, which signals through a conserved PI 3-kinase/AKT pathway that ultimately downregulates DAF-16/FOXO activity. Importantly, studies have shown that multiple pathways intersect with the insulin/IGF-1 signaling pathway and impinge on DAF-16 for their regulation. Therefore, in C. elegans, the single FOXO family member, DAF-16, integrates signals from several pathways and then regulates its many downstream target genes.

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