Gene interactions and pathways from curated databases and text-mining
J Biol Chem 2006, PMID: 16870609

Nutrient-dependent multimerization of the mammalian target of rapamycin through the N-terminal HEAT repeat region.

Takahara, Terunao; Hara, Kenta; Yonezawa, Kazuyoshi; Sorimachi, Hiroyuki; Maeda, Tatsuya

The mammalian target of rapamycin (mTOR) plays a pivotal role in the regulation of cell growth in response to a variety of signals such as nutrients and growth factors. mTOR forms two distinct complexes in vivo. mTORC1 (mTOR complex 1) is rapamycin-sensitive and regulates the rate of protein synthesis in part by phosphorylating two well established effectors, S6K1 (p70 ribosomal S6 kinase 1) and 4E-BP1 (eukaryotic initiation factor 4E-binding protein 1). mTORC2 is rapamycin-insensitive and likely regulates actin organization and activates Akt/protein kinase B. Here, we show that mTOR forms a multimer via its N-terminal HEAT repeat region in mammalian cells. mTOR multimerization is promoted by amino acid sufficiency, although the state of multimerization does not directly correlate with the phosphorylation state of S6K1. mTOR multimerization was insensitive to rapamycin treatment but hindered by butanol treatment, which inhibits phosphatidic acid production by phospholipase D. We also found that mTOR forms a multimer in both mTORC1 and mTORC2. In addition, Saccharomyces cerevisiae TOR proteins Tor1p and Tor2p also exist as homomultimers. These results suggest that TOR multimerization is a conserved mechanism for TOR functioning.

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Text Mining Data

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Manually curated Databases

  • IRef Biogrid Interaction: MTOR — MTOR (physical association, affinity chromatography technology)
  • IRef Hprd Interaction: MTOR — MTOR (in vitro)
  • IRef Hprd Interaction: MTOR — MTOR (in vivo)
  • IRef Innatedb Interaction: MTOR — MTOR (unknown, -)
In total, 1 gene pairs are associated to this article in curated databases