What is the role of Foxo1?

In addition to regulating muscle mass, FoxO1 is involved in altering its function. It promotes the expression of genes involved in energy metabolism resulting in the transition from carbohydrate oxidation to lipid oxidation under conditions such as fasting and exercise (Bastie et al., 2005).

What activates Foxo1?

Fatty acids in the beta cells activate FOXO1, resulting in apoptosis of the beta cells.

How does insulin regulate Foxo1?

Insulin also results in a rapid and dose-dependent phosphorylation of Foxo1. Glucose-induced depolarization of β-cells is known to result in insulin secretion, and the addition of exogenous insulin in other mammalian cells has been shown to induce Foxo1 phosphorylation (25,26).

What is dFoxO?

dFoxO, the equivalent of nematode DAF‐16/FoxO and mammalian FOXO3A, has been shown to be a key transcriptional regulator of the insulin pathway that modulates growth and proliferation in D. melanogaster (Puig & Mattila, 2011).

Where is the prolactin receptor located on the chromosome?

The prolactin receptor ( PRLR) is a type I cytokine receptor encoded in humans by the PRLR gene on chromosome 5p13-14. The PRLR binds prolactin (PRL) as a transmembrane receptor.

How does the PRLR bind to the prolactin receptor?

The PRLR binds prolactin (PRL) as a transmembrane receptor. Thus the PRLR contains an extracellular region to bind PRL, a transmembrane region, and a cytoplasmatic region. The PRLR can also bind to and be activated by growth hormone (GH) and human placental lactogen (hPL), in addition to prolactin.

How is the prolactin receptor related to JAK2?

The prolactin receptor is a member of the cytokine receptors that lacks an intrinsic kinase domain but possesses a JAK2-associating region. Upon prolactin stimulation, the prolactin receptor transduces signals through the activation of JAK2, leading to the phosphorylation of JAK2.

How does FOXO1 increase transcriptional activity of SIRT1?

Resveratrol, an activator of Sirt1, increases the transcriptional activity of FoxO1 and triggers Akt phosphorylation in heart. Importantly, FoxO-mediated increases in Akt activity diminish insulin signaling, as manifested by reduced Akt phosphorylation, reduced membrane translocation of Glut4, and decreased insulin-triggered glucose uptake.