Rab escort protein 1

Rab escort protein 1 (REP1) also known as rab proteins geranylgeranyltransferase component A 1 is an enzyme that in humans is encoded by the CHM gene.

CHM
Identifiers
Aliases	CHM, DXS540, GGTA, HSD-32, REP-1, TCD, Rab escort protein 1, CHM Rab escort protein
External IDs	OMIM: 300390; MGI: 892979; HomoloGene: 334; GeneCards: CHM; OMA:CHM - orthologs
Gene location (Human) Chr. X chromosome (human) Band Xq21.2 Start 85,861,180 bp End 86,047,561 bp
Gene location (Mouse) Chr. X chromosome (mouse) Band X|X E1 Start 111,950,290 bp End 112,095,214 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in endothelial cell Brodmann area 23 middle temporal gyrus germinal epithelium visceral pleura islet of Langerhans postcentral gyrus parietal pleura Achilles tendon lateral nuclear group of thalamus Top expressed in ciliary body subdivision of hippocampus Region I of hippocampus proper retinal pigment epithelium Epithelium of choroid plexus iris lateral geniculate nucleus saccule medial geniculate nucleus medial dorsal nucleus More reference expression data BioGPS More reference expression data
Gene ontology Molecular function Rab geranylgeranyltransferase activity GTPase activator activity GDP-dissociation inhibitor activity Cellular component cytoplasm Rab-protein geranylgeranyltransferase complex cytosol nucleus Biological process positive regulation of GTPase activity intracellular protein transport protein geranylgeranylation response to stimulus visual perception protein targeting to membrane regulation of catalytic activity small GTPase mediated signal transduction regulation of apoptotic process post-translational protein modification vesicle-mediated transport Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1121 12662 Ensembl ENSG00000188419 ENSMUSG00000025531 UniProt P24386 Q9QXG2 RefSeq (mRNA) NM_000390 NM_001037312 NM_001145414 NM_001320959 NM_001362517 NM_001362518 NM_001362519 NM_152579 NM_018818 NM_001370788 NM_001370789 NM_001370790 RefSeq (protein) NP_000381 NP_001138886 NP_001307888 NP_001349446 NP_001349447 NP_001349448 n/a Location (UCSC) Chr X: 85.86 – 86.05 Mb Chr X: 111.95 – 112.1 Mb PubMed search
Wikidata
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Function

This gene encodes component A of the RAB geranylgeranyl transferase holoenzyme. In the dimeric holoenzyme, this subunit binds unprenylated Rab GTPases and then presents them to the catalytic Rab GGTase subunit for the geranylgeranyl transfer reaction. Rab GTPases need to be geranylgeranyled on either one or two cysteine residues in their C-terminus to localize to the correct intracellular membrane.

Interactions

CHM (gene) has been shown to interact with RAB1A, RAB7A and RAB3A.

Clinical significance

Mutations in this gene are a cause of choroideremia; also known as tapetochoroidal dystrophy (TCD). This X-linked disease is characterized by progressive dystrophy of the choroid, retinal pigment epithelium and retina.

See also

• Rab (G-protein)

Further reading

• Sankila EM, Tolvanen R, van den Hurk JA, Cremers FP, de la Chapelle A (1993). "Aberrant splicing of the CHM gene is a significant cause of choroideremia". Nat. Genet. 1 (2): 109–13. doi:10.1038/ng0592-109. PMID 1302003. S2CID 23500961.
• Merry DE, Jänne PA, Landers JE, Lewis RA, Nussbaum RL (1992). "Isolation of a candidate gene for choroideremia". Proc. Natl. Acad. Sci. U.S.A. 89 (6): 2135–9. Bibcode:1992PNAS...89.2135M. doi:10.1073/pnas.89.6.2135. PMC 48611. PMID 1549574.
• van den Hurk JA, van de Pol TJ, Molloy CM, Brunsmann F, Rüther K, Zrenner E, Pinckers AJ, Pawlowitzki IH, Bleeker-Wagemakers EM, Wieringa B (1992). "Detection and characterization of point mutations in the choroideremia candidate gene by PCR-SSCP analysis and direct DNA sequencing". Am. J. Hum. Genet. 50 (6): 1195–202. PMC 1682553. PMID 1598901.
• Fodor E, Lee RT, O'Donnell JJ (1991). "Analysis of choroideraemia gene". Nature. 351 (6328): 614. Bibcode:1991Natur.351..614F. doi:10.1038/351614b0. PMID 1904992. S2CID 5447515.
• Cremers FP, van de Pol DJ, van Kerkhoff LP, Wieringa B, Ropers HH (1990). "Cloning of a gene that is rearranged in patients with choroideraemia". Nature. 347 (6294): 674–7. Bibcode:1990Natur.347..674C. doi:10.1038/347674a0. PMID 2215697. S2CID 4347627.
• Cremers FP, Sankila EM, Brunsmann F, Jay M, Jay B, Wright A, Pinckers AJ, Schwartz M, van de Pol DJ, Wieringa B (1990). "Deletions in patients with classical choroideremia vary in size from 45 kb to several megabases". Am. J. Hum. Genet. 47 (4): 622–8. PMC 1683797. PMID 2220804.
• Donnelly P, Menet H, Fouanon C, Herbert O, Moisan JP, Le Roux MG, Pascal O (1994). "Missense mutation in the choroideremia gene". Hum. Mol. Genet. 3 (6): 1017. doi:10.1093/hmg/3.6.1017. PMID 7951216.
• Alexandrov K, Horiuchi H, Steele-Mortimer O, Seabra MC, Zerial M (1994). "Rab escort protein-1 is a multifunctional protein that accompanies newly prenylated rab proteins to their target membranes". EMBO J. 13 (22): 5262–73. doi:10.1002/j.1460-2075.1994.tb06860.x. PMC 395482. PMID 7957092.
• van Bokhoven H, van den Hurk JA, Bogerd L, Philippe C, Gilgenkrantz S, de Jong P, Ropers HH, Cremers FP (1995). "Cloning and characterization of the human choroideremia gene". Hum. Mol. Genet. 3 (7): 1041–6. doi:10.1093/hmg/3.7.1041. PMID 7981670.
• Cremers FP, Armstrong SA, Seabra MC, Brown MS, Goldstein JL (1994). "REP-2, a Rab escort protein encoded by the choroideremia-like gene". J. Biol. Chem. 269 (3): 2111–7. doi:10.1016/S0021-9258(17)42142-9. PMID 8294464.
• Seabra MC, Brown MS, Goldstein JL (1993). "Retinal degeneration in choroideremia: deficiency of rab geranylgeranyl transferase". Science. 259 (5093): 377–81. Bibcode:1993Sci...259..377S. doi:10.1126/science.8380507. PMID 8380507.
• Schwartz M, Rosenberg T, van den Hurk JA, van de Pol DJ, Cremers FP (1993). "Identification of mutations in Danish choroideremia families". Hum. Mutat. 2 (1): 43–7. doi:10.1002/humu.1380020108. PMID 8477262. S2CID 40191966.
• Overmeyer JH, Wilson AL, Erdman RA, Maltese WA (1998). "The putative "switch 2" domain of the Ras-related GTPase, Rab1B, plays an essential role in the interaction with Rab escort protein". Mol. Biol. Cell. 9 (1): 223–35. doi:10.1091/mbc.9.1.223. PMC 25245. PMID 9437002.
• Alexandrov K, Simon I, Iakovenko A, Holz B, Goody RS, Scheidig AJ (1998). "Moderate discrimination of REP-1 between Rab7 x GDP and Rab7 x GTP arises from a difference of an order of magnitude in dissociation rates". FEBS Lett. 425 (3): 460–4. doi:10.1016/S0014-5793(98)00290-7. PMID 9563513. S2CID 39125409.
• Raffaniello RD, Raufman JP (1999). "Cytosolic RAB3D is associated with RAB escort protein (REP), not RAB-GDP dissociation inhibitor (GDI), in dispersed chief cells from guinea pig stomach". J. Cell. Biochem. 72 (4): 540–8. doi:10.1002/(SICI)1097-4644(19990315)72:4<540::AID-JCB9>3.0.CO;2-D. PMID 10022613. S2CID 35820873.
• Thomä NH, Iakovenko A, Kalinin A, Waldmann H, Goody RS, Alexandrov K (2001). "Allosteric regulation of substrate binding and product release in geranylgeranyltransferase type II". Biochemistry. 40 (1): 268–74. doi:10.1021/bi002034p. PMID 11141079.
• Syed N, Smith JE, John SK, Seabra MC, Aguirre GD, Milam AH (2001). "Evaluation of retinal photoreceptors and pigment epithelium in a female carrier of choroideremia". Ophthalmology. 108 (4): 711–20. doi:10.1016/S0161-6420(00)00643-6. PMID 11297488.
• Rak A, Reents R, Pylypenko O, Niculae A, Sidorovitch V, Thomä NH, Waldmann H, Schlichting I, Goody RS, Alexandrov K (2002). "Crystallization and preliminary X-ray diffraction analysis of the Rab escort protein-1 in complex with Rab geranylgeranyltransferase". J. Struct. Biol. 136 (2): 158–61. doi:10.1006/jsbi.2001.4433. PMID 11886217.

External links

• GeneReviews/NCBI/NIH/UW entry on Choroideremia
• Rab escort protein 1, human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)