Download MendeleyIRS-1 acts as an endocytic regulator of IGF-I receptor to facilitate sustained IGF signaling
Yoneyama, Y., Lanzerstorfer, P., Niwa, H., Umehara, T., Shibano, T., Yokoyama, S., Chida, K., Weghuber, J., Hakuno, F., Takahashi, S.I.(2018) Elife 7
- PubMed: 29661273
- DOI: https://doi.org/10.7554/eLife.32893
- Primary Citation of Related Structures:
5WRK, 5WRL, 5WRM - PubMed Abstract:
Insulin-like growth factor-I receptor (IGF-IR) preferentially regulates the long-term IGF activities including growth and metabolism. Kinetics of ligand-dependent IGF-IR endocytosis determines how IGF induces such downstream signaling outputs. Here, we find that the insulin receptor substrate (IRS)-1 modulates how long ligand-activated IGF-IR remains at the cell surface before undergoing endocytosis in mammalian cells. IRS-1 interacts with the clathrin adaptor complex AP2. IRS-1, but not an AP2-binding-deficient mutant, delays AP2-mediated IGF-IR endocytosis after the ligand stimulation. Mechanistically, IRS-1 inhibits the recruitment of IGF-IR into clathrin-coated structures; for this reason, IGF-IR avoids rapid endocytosis and prolongs its activity on the cell surface. Accelerating IGF-IR endocytosis via IRS-1 depletion induces the shift from sustained to transient Akt activation and augments FoxO-mediated transcription. Our study establishes a new role for IRS-1 as an endocytic regulator of IGF-IR that ensures sustained IGF bioactivity, independent of its classic role as an adaptor in IGF-IR signaling.
Organizational Affiliation:
Department of Animal Resource Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
