RAB4A
RAB4A (Ras-related protein Rab-4A, also known as HRES-1/RAB4 or RAB4) is a small GTPase of the Rab family that regulates intracellular membrane trafficking. It is associated with early endosomes and is involved in their sorting and recycling. Browse Assay Genie's current range of RAB4A research reagents below, or read on for the biology behind the target.
Rab proteins are key regulators of intracellular membrane trafficking, acting from the formation of transport vesicles through to their fusion with target membranes. Like other Rabs, RAB4A cycles between an inactive GDP-bound form and an active GTP-bound form. The GTP-bound state recruits distinct sets of downstream effectors that are directly responsible for vesicle formation, movement, tethering and fusion. RAB4A is involved in protein transport and vesicular traffic, and it is classified as a GTPase (EC 3.6.5.2).
The RAB4A gene belongs to the largest group in the Ras superfamily of small GTPases, and the encoded protein belongs to the Rab family of the small GTPase superfamily. The protein is found at the membrane and in the cytoplasm, with localisation to early endosome and recycling endosome membranes. Its role in endosomal sorting and recycling includes regulating the return of receptors from endosomes to the plasma membrane. Alternatively spliced transcript variants have been observed for this gene.
Specific functions have been assigned to RAB4A in receptor and cell-type contexts. It mediates VEGFR2 endosomal trafficking, which enhances VEGFR2 signalling, and it acts as a regulator of platelet alpha-granule release during platelet activation and aggregation. HGNC places the gene in the RAB, member RAS oncogene GTPases group, and orthologues are annotated in mouse and rat as Rab4a. Researchers studying endosomal recycling often use RAB4A alongside other Rab proteins as a marker of recycling compartments.
RAB4A is associated with early endosomes and is involved in their sorting and recycling, making it a reference point for studying endocytic traffic.
The protein regulates the recycling of receptors from endosomes to the plasma membrane, which is relevant to how cells control surface receptor levels.
RAB4A mediates VEGFR2 endosomal trafficking to enhance VEGFR2 signalling, linking vesicle transport to growth factor receptor output.
RAB4A regulates platelet alpha-granule release during activation and aggregation, so it is of interest in studies of platelet secretion.
RAB4A is a small GTPase that regulates membrane trafficking. It is associated with early endosomes, where it is involved in sorting and recycling, including the return of receptors to the plasma membrane. It also mediates VEGFR2 endosomal trafficking and regulates platelet alpha-granule release.
The UniProt protein name is Ras-related protein Rab-4A, and the HGNC full name is RAB4A, member RAS oncogene family. Aliases include HRES-1/RAB4 and RAB4. The gene is reported to produce alternatively spliced transcript variants.
Yes. Mouse and rat orthologues are both annotated as Rab4a. As a member of the Rab family of the small GTPase superfamily, it shares the GDP/GTP cycle of other Rabs. Check the datasheet of any product for its validated reactivity.
Other Rab family small GTPases and trafficking regulators, including endosomal and recycling pathway partners.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P20338; product specifications from Assay Genie datasheets.