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MTORbeta splicing isoform promotes cell proliferation and tumorigenesis.

ABSTRACT: The mTOR (mammalian target of rapamycin) promotes growth in response to nutrients and growth factors and is deregulated in numerous pathologies, including cancer. The mechanisms by which mTOR senses and regulates energy metabolism and cell growth are relatively well understood, whereas the molecular events underlining how it mediates survival and proliferation remain to be elucidated. Here, we describe the existence of the mTOR splicing isoform, TOR beta, which, in contrast to the full-length protein (mTOR alpha), has the potential to regulate the G(1) phase of the cell cycle and to stimulate cell proliferation. mTOR beta is an active protein kinase that mediates downstream signaling through complexing with Rictor and Raptor proteins. Remarkably, overexpression of mTOR beta transforms immortal cells and is tumorigenic in nude mice and therefore could be a proto-oncogene.

SUBMITTER: Panasyuk G

PROVIDER: S-EPMC2781479 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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mTORbeta splicing isoform promotes cell proliferation and tumorigenesis.

Panasyuk Ganna G Nemazanyy Ivan I Zhyvoloup Aleksander A Filonenko Valeriy V Davies Derek D Robson Mathew M Pedley R Barbara RB Waterfield Michael M Gout Ivan I

The Journal of biological chemistry 20090902 45

The mTOR (mammalian target of rapamycin) promotes growth in response to nutrients and growth factors and is deregulated in numerous pathologies, including cancer. The mechanisms by which mTOR senses and regulates energy metabolism and cell growth are relatively well understood, whereas the molecular events underlining how it mediates survival and proliferation remain to be elucidated. Here, we describe the existence of the mTOR splicing isoform, TOR beta, which, in contrast to the full-length pr ...[more]

PMID: 19726679

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