rab21 proto-oncogene protein; Ras-related protein Rab-21 (RAB21, KIAA0118)

Function

• regulates integrin internalization & recycling
• does not influence traffic of endosomally translocated receptors in general
• may regulate cell adhesion & migration (putative)
• during the mitosis of adherent cells, controls endosomal trafficking of integrins required for completion of cytokinesis
• interacts with the cytoplasmic tail of integrins ITGA1, ITGA2, ITGA5, ITGA6, ITGA11 & ITGB1 (putative)

Structure

belongs to the small GTPase superfamily, Rab family

Compartment

• endoplasmic reticulum membrane; lipid-anchor (putative).
• Golgi apparatus membrane.
• early endosome membrane
• cytoplasmic vesicle membrane
• in nonpolarized epithelial Caco-2 cells, found in the endoplasmic reticulum
• in polarized cells, observed in vesicles in the apical cytoplasm during mitosis; in mid-telophase, localized in the ingressing cleavage furrow; in late telophase, detected at the opposite poles of the daughter cells, in vesicles at the base of lamellipodia formed by the separating daughter cells

Expression

• widely expressed
• in jejunal tissue, predominantly expressed in the apical region of the epithelial cell layer of the villi; weak expression, if any, in crypt epithelium; capillary endothelium & some cell types in the lamina propria also show expression

More general terms

• rab subfamily protein

Database

• UniProt: http://www.uniprot.org/uniprot/Q9UL25.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=23011
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:23011
• OMIM: https://mirror.omim.org/entry/612398