Disease relevance of RAB2A

• To assess the potential role of the NH2 terminus in Rab2 function, a peptide corresponding to the first 13 amino acids following the initiator methionine was introduced into an in vitro assay that efficiently reconstitutes transport of vesicular stomatitis virus glycoprotein from the ER to the Golgi stack [1].
• The overexpression of the Rab2 protein in peripheral mononuclear cells is demonstrated from 13 out of 17 patients exhibiting a Sézary syndrome [2].
• Sporobolus Rab2 was expressed in Escherichia coli yielding a protein with an apparent molecular mass of ca. 30 kDa which was shown to have the ability to bind GTP [3].

High impact information on RAB2A

• Cytosols containing high levels of rab2 or mutant rab5 with the 9 carboxy-terminal amino acids deleted, which bind GTP on blots, had no effects [4].
• To define the region mediating their specific localization, we transiently expressed rab2, rab5 and rab7 hybrid proteins in BHK cells, and determined their intracellular localization by immunofluorescence confocal microscopy and subcellular fractionation [5].
• A GRASP55-rab2 effector complex linking Golgi structure to membrane traffic [6].
• GTP-binding mutants of rab1 and rab2 are potent inhibitors of vesicular transport from the endoplasmic reticulum to the Golgi complex [7].
• Mutants in guanine nucleotide exchange or hydrolysis of the rab2 protein were also strong trans dominant transport inhibitors [7].

Chemical compound and disease context of RAB2A

• To determine whether the NH2 terminus of Rab2 was required for its activity in vivo, a trans dominant mutant of Rab2 that inhibits ER to Golgi transport was progressively truncated and analyzed for its effect on vesicular stomatitis virus glycoprotein transport in a vaccinia-based transient expression system [1].

Biological context of RAB2A

• These results demonstrate that GRASP55 and golgin-45 form a rab2 effector complex on medial-Golgi essential for normal protein transport and Golgi structure [6].
• We suggest that at least three members of the rab family (rab1a, rab1b, and rab2) use GTP hydrolysis to regulate components of the transport machinery involved in vesicle traffic between early compartments of the secretory pathway [7].
• Src-dependent aprotein kinase C iota/lambda (aPKCiota/lambda) tyrosine phosphorylation is required for aPKCiota/lambda association with Rab2 and glyceraldehyde-3-phosphate dehydrogenase on pre-golgi intermediates [8].
• The rab1 and rab2 proteins lack the carboxyl-terminal amino acid motif common to all previously identified isoprenylated proteins, i.e. CXXX, where X is an unspecified amino acid [9].
• Several lines of evidence are shown suggesting that the Rab2 overexpression can be related not to leukemic cells but to a subset of peripheral lymphocytes with a CD2+ phenotype [2].

Anatomical context of RAB2A

• The small GTPase Rab2 is a resident of pre-Golgi intermediates and required for protein transport from the endoplasmic reticulum (ER) to the Golgi complex (Tisdale, E. J., Bourne, J. R., Khosravi-Far, R. , Der, C. J., and Balch, W. E. (1992) J. Cell Biol. 119, 749-761) [1].
• Circulating monocyte and lymphocyte populations from cancer patients are under analysis to correlate the Rab2 protein overexpression to a peculiar subset of cells [10].
• Like aPKCiota/lambda, the membranes contained a negligible amount of beta-COP that was reflected by the drastic reduction in Rab2-dependent vesicle formation [8].
• The small GTPase Rab2 is required for membrane transport between the endoplasmic reticulum (ER) and the Golgi complex [8].
• Identification of rab2 as a tubulovesicle-membrane-associated protein in rabbit gastric parietal cells [11].

Associations of RAB2A with chemical compounds

• The combined results suggest that the NH2 terminus of Rab2 is required for its function and for direct interaction with components of the transport machinery involved in the maturation of pre-Golgi intermediates [1].
• Herein, we demonstrate that terminal cysteine residues in the rab1B, rab2, and rab5 proteins undergo thioether modification by isoprenyl groups when these proteins are translated in vitro in the presence of a radiolabeled isoprenoid precursor, [3H]mevalonate [9].
• Earlier work on S. stapfianus concluded that the plant hormone ABA has little effect on inducing desiccation tolerance, however Rab2 transcript does exhibit a small increase in accumulation in response to exogenous ABA [3].

Other interactions of RAB2A

• Two sequences corresponded to novel isoforms of Rab2 and Rab9 [12].
• The rab1, rab2, rab3A, and rab4 proteins are the human counterparts of the rat rab gene products that we have previously characterized [13].
• Phylogenetic analysis showed that PGP1 belongs to YPT/RAB group of the small GTP-binding protein and is a homologue of RAB2 [14].

Analytical, diagnostic and therapeutic context of RAB2A

• Utilizing a PCR the rab2 cDNA sequence from rabbit parietal cells was obtained, and it showed only one amino acid difference compared with the human sequence [11].
• A possible role for Rab2 with respect to desiccation tolerance and damage repair is discussed [3].
• Accumulation of Rab2 transcript was also evident during drying and rehydration of the roots of S. stapfianus, as well as in leaves of the desiccation-sensitive grass Sporobolus pyramidalis [3].

References