Primary Identifier | IPR004083 | Type | Family |
Short Name | Raptor |
description | This family consists of Raptor (regulatory associated protein of TOR) and its orthologs which includes Kog1p of Saccharomyces cerevisiae (Baker's yeast), a highly conserved 150kDa TOR-binding protein [, , ]. The target-of-rapamycin (TOR) proteins are protein kinases that were first identified in S. cerevisiae through mutants that conferred resistance to growth inhibition induced by the immunosuppressive macrolide rapamycin [].All Raptor orthologs contain a unique conserved region in their N-terminal half (raptor N-terminal conserved, also called the RNC domain) followed by three HEAT (huntingtin, elongation factor 3, A subunit of protein phosphatase 2A and TOR1) repeats and seven WD-40 repeats near the C terminus. Research on mammalian Raptor suggests that its association with mTOR promotes the phosphorylation of downstream effectors in nutrient-stimulated cells [, ]. In concordance with these observations, the binding of TOR to Raptor or to Kog1p []is necessary for TOR signalling in vivo in Caenorhabditis elegans and S. cerevisiae [, ].The RNC domain consists of 3 blocks with at least 67 to 79% sequence similarity and is predicted to have a high propensity to form alpha helices. The RNC domain is characterised by the presence of invariant catalytic Cys-His dyad, which is structurally and evolutionarily related to known caspases, suggesting that the raptor proteins may have protease activity []. |