Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.


Sci. Signal., 17 June 2008
Vol. 1, Issue 24, p. ec225
[DOI: 10.1126/scisignal.124ec225]


Nutrient Sensing Location Matters

L. Bryan Ray

Science, Science Signaling, AAAS, Washington, DC 20005, USA

The signaling pathway through which cells modulate protein synthesis and cell growth in response to amino acids has been tricky to unravel. Sancak et al. add a key piece to the puzzle with experiments that reveal a role for a group of small guanosine triphosphatases (GTPases) known as Rag proteins. RagC associates with the mTORC1 protein kinase complex, a key regulator of cell growth. This interaction of Rag proteins with mTORC1 appears to be necessary and sufficient to convey nutrient availability signals when cells are exposed to amino acids. The physical interaction of Rag proteins with mTORC1 appears not to regulate activity of mTOR but to influence its localization within the endomembrane system of the cell.

Y. Sancak, T. R. Peterson, Y. D. Shaul, R. A. Lindquist, C. C. Thoreen, L. Bar-Peled, D. M. Sabatini, The Rag GTPases bind raptor and mediate amino acid signaling to mTORC1. Science 320, 1496-1501 (2008). [Abstract] [Full Text]

Citation: L. B. Ray, Location Matters. Sci. Signal. 1, ec225 (2008).

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882