RALBP1

RALBP1 plays a role in receptor-mediated endocytosis and is a downstream effector of the small GTP-binding protein RAL (see RALA; MIM 179550). Small G proteins, such as RAL, have GDP-bound inactive and GTP-bound active forms, which shift from the inactive to the active state through the action of RALGDS (MIM 601619), which in turn is activated by RAS (see HRAS; MIM 190020) (summary by Feig, 2003 [PubMed 12888294]).[supplied by OMIM, Nov 2010]

RalA Binding Protein 1

Multifunctional protein that functions as a downstream effector of RALA and RALB (PubMed:7673236).
As a GTPase-activating protein/GAP can inactivate CDC42 and RAC1 by stimulating their GTPase activity (PubMed:7673236).
As part of the Ral signaling pathway, may also regulate ligand-dependent EGF and insulin receptors-mediated endocytosis (PubMed:10910768, PubMed:12775724).
During mitosis, may act as a scaffold protein in the phosphorylation of EPSIN/EPN1 by the mitotic kinase cyclin B-CDK1, preventing endocytosis during that phase of the cell cycle (PubMed:12775724).
During mitosis, also controls mitochondrial fission as an effector of RALA (PubMed:21822277).
Recruited to mitochondrion by RALA, acts as a scaffold to foster the mitotic kinase cyclin B-CDK1-mediated phosphorylation and activation of DNM1L (PubMed:21822277).
Could also function as a primary ATP-dependent active transporter for glutathione conjugates of electrophiles. May also actively catalyze the efflux of a wide range of substrates including xenobiotics like doxorubicin (DOX) contributing to cell multidrug resistance.

Biological Process chemotaxisManual Assertion Based On ExperimentTAS:ProtInc
Biological Process doxorubicin transportManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process endocytosisManual Assertion Based On ExperimentIBA:GO_Central
Biological Process positive regulation of GTPase activityManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process positive regulation of mitochondrial fissionManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process positive regulation of protein phosphorylationManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process regulation of Cdc42 protein signal transductionISS:UniProtKB
Biological Process regulation of GTPase activityManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process regulation of small GTPase mediated signal transductionTAS:Reactome
Biological Process small GTPase mediated signal transductionManual Assertion Based On ExperimentIPI:UniProtKB
Biological Process transmembrane transportManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process xenobiotic detoxification by transmembrane export across the plasma membraneManual Assertion Based On ExperimentIDA:UniProtKB

Cell membrane
Cytoplasm, cytosol
Cytoplasm, cytoskeleton, spindle pole
Nucleus
Mitochondrion
Cytosolic protein that transiently associates with the mitotic spindle poles in early prophase, and dissociates from them after completion of mitosis (By similarity).
Targeted to the plasma membrane through its interaction with RALB, directed by FGF signaling. Docking on the membrane is required to transduce the Ral signal (By similarity).
Recruited by RALA to the mitochondrion during mitosis where it regulates mitochondrial fission (PubMed:21822277).
Nuclear localization is cell cycle dependent while membrane localization is seen in adherent cells (PubMed:22319010).
The region involved in membrane association could form transmembrane domains and expose a part of the protein extracellularly (Probable)

Tyrosine-phosphorylated upon stimulation of cells with EGF.
May undergo proteolytic cleavage to give peptides which reassemble to form a transporter complex.