RRAGB
Description
The RRAGB (Ras related GTP binding B) is a protein-coding gene located on chromosome X.
Ras-related GTP-binding protein B is a protein that in humans is encoded by the RRAGB gene. Ras-homologous GTPases constitute a large family of signal transducers that alternate between an activated, GTP-binding state and an inactivated, GDP-binding state. These proteins represent cellular switches that are operated by GTP-exchange factors and factors that stimulate their intrinsic GTPase activity. All GTPases of the Ras superfamily have in common the presence of six conserved motifs involved in GTP/GDP binding, three of which are phosphate-/magnesium-binding sites (PM1-PM3) and three of which are guanine nucleotide-binding sites (G1-G3). Transcript variants encoding distinct isoforms have been identified.
Guanine nucleotide-binding protein that plays a crucial role in the cellular response to amino acid availability through regulation of the mTORC1 signaling cascade (PubMed:18497260, PubMed:20381137, PubMed:23723238, PubMed:24095279). Forms heterodimeric Rag complexes with RagC/RRAGC or RagD/RRAGD and cycles between an inactive GDP-bound and an active GTP-bound form: RagB/RRAGB is in its active form when GTP-bound RagB/RRAGB forms a complex with GDP-bound RagC/RRAGC (or RagD/RRAGD) and in an inactive form when GDP-bound RagB/RRAGB heterodimerizes with GTP-bound RagC/RRAGC (or RagD/RRAGD) (PubMed:18497260, PubMed:20381137, PubMed:23723238, PubMed:24095279). In its GTP-bound active form, promotes the recruitment of mTORC1 to the lysosomes and its subsequent activation by the GTPase RHEB (PubMed:18497260, PubMed:20381137, PubMed:23723238). Involved in the RCC1/Ran-GTPase pathway (PubMed:9394008). {ECO:0000269|PubMed:18497260, ECO:0000269|PubMed:20381137, ECO:0000269|PubMed:23723238, ECO:0000269|PubMed:24095279, ECO:0000269|PubMed:9394008}
RRAGB is also known as RAGB, bA465E19.1.
