AKT1S1

AKT1S1 is a proline-rich substrate of AKT (MIM 164730) that binds 14-3-3 protein (see YWHAH, MIM 113508) when phosphorylated (Kovacina et al., 2003 [PubMed 12524439]).[supplied by OMIM, Mar 2008]

AKT1 Substrate 1

Subunit of mTORC1, which regulates cell growth and survival in response to nutrient and hormonal signals. mTORC1 is activated in response to growth factors or amino acids. Growth factor-stimulated mTORC1 activation involves a AKT1-mediated phosphorylation of TSC1-TSC2, which leads to the activation of the RHEB GTPase that potently activates the protein kinase activity of mTORC1. Amino acid-signaling to mTORC1 requires its relocalization to the lysosomes mediated by the Ragulator complex and the Rag GTPases. Activated mTORC1 up-regulates protein synthesis by phosphorylating key regulators of mRNA translation and ribosome synthesis. mTORC1 phosphorylates EIF4EBP1 and releases it from inhibiting the elongation initiation factor 4E (eiF4E). mTORC1 phosphorylates and activates S6K1 at 'Thr-389', which then promotes protein synthesis by phosphorylating PDCD4 and targeting it for degradation. Within mTORC1, AKT1S1 negatively regulates mTOR activity in a manner that is dependent on its phosphorylation state and binding to 14-3-3 proteins. Inhibits RHEB-GTP-dependent mTORC1 activation. Substrate for AKT1 phosphorylation, but can also be activated by AKT1-independent mechanisms. May also play a role in nerve growth factor-mediated neuroprotection.

Negative regulation of cell size Source: UniProtKB
Negative regulation of protein kinase activity Source: UniProtKB
Negative regulation of TOR signaling Source: UniProtKB
Neurotrophin TRK receptor signaling pathway Source: InterPro
Regulation of apoptotic process Source: UniProtKB
Regulation of cellular response to heat Source: Reactome
Regulation of neuron apoptotic process Source: UniProtKB

Cytosol. Found in the cytosolic fraction of the brain.

Phosphorylated by AKT1 (PubMed:12524439). Phosphorylation at Thr-246 by DYRK3 relieves inhibitory function on mTORC1 (PubMed:23415227).