| Primary Identifier | IPR035974 | Type | Homologous_superfamily |
| Short Name | Rap/Ran-GAP_sf |
| description | Structural domains comprising this superfamily share the structure of two shown to be homologous GTPase activating proteins for Rap and Ran. Both are Ras-like guanine-nucleotide-binding proteins (GNBPs) involved in a variety of signal-transduction processes and their activity is regulated by GEFs and GAPs.Rap small G proteins have been implicated in various cellular processes such as exocytosis, cAMP signalling, cell adhesion and cell proliferation. Rap proteins acts as molecular switches, with an active GTP-bound form and an inactive GDP-bound form []. The inactive GDP bound form is promoted by GTPase-activating proteins (GAPs). GAP proteins specific for Rap contain a conserved region of around 200 amino-acid residues, the RapGAP domain. This domain can accelerate the GTP hydrolysis activity of Rap by five orders of magnitude [].Ran, also known as GTP-binding nuclear protein, is on the other hand essential for the translocation of RNA and proteins through the nuclear pore complex and has been implicated in the control of DNA synthesis and cell cycle progression. Proteins known to contain a Rap-GAP domain include:RAP1 GTPase activating protein (RAP1GAP).Mammalian tuberin protein, the product of a familial tuberous sclerosis gene which, when deleted, causes begnin tumours. It also have a GAPactivity for Rab5 [].Drosophila Gigas protein, an homologue of tuberin involved in regulation of cell cycle.Mammalian tuberin-like protein TULIP.GTPase-activating protein Spa-1. It functions as a negative regulator for the activation of Rap1, thereby having a negative effect on cell adhesion[]. |
