Regulatory associated protein of TOR (IPR004083)

Short name: Raptor

Overlapping homologous superfamilies


Family relationships



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 [PMID: 12150925, PMID: 12150926, PMID: 12408816]. 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 [PMID: 8387896].

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 [PMID: 12150925, PMID: 12150926]. In concordance with these observations, the binding of TOR to Raptor or to Kog1p [PMID: 12408816] is necessary for TOR signalling in vivo in Caenorhabditis elegans and S. cerevisiae [PMID: 12150926, PMID: 12408816].

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 [PMID: 15450605].

GO terms

Biological Process

GO:0031929 TOR signaling

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0031931 TORC1 complex

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.