Rab escort protein 1 explained

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.^{[1] [2]}

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 on either one or two cysteine residues in their C-terminus to localize to the correct intracellular membrane.^[2]

Interactions

CHM (gene) has been shown to interact with RAB1A,^[3] RAB7A^{[4] [5]} and RAB3A.^{[3] [6]}

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.^[2]

See also

• Rab (G-protein)

Further reading

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

External links

• GeneReviews/NCBI/NIH/UW entry on Choroideremia

Notes and References

1. Molloy CM, van de Pol TJ, Brohet RM, Ropers HH, Cremers FP . Three RFLPs for pZ11 (DXS540) in the choroideremia gene at Xq21.2 . Nucleic Acids Res . 20 . 6 . 1434 . May 1992 . 1373238 . 312214 . 10.1093/nar/20.6.1434 .
2. Web site: Entrez Gene: CHM choroideremia (Rab escort protein 1).
3. Cremers FP, Armstrong SA, Seabra MC, Brown MS, Goldstein JL . REP-2, a Rab escort protein encoded by the choroideremia-like gene . J. Biol. Chem. . 269 . 3 . 2111–7 . Jan 1994 . 10.1016/S0021-9258(17)42142-9 . 8294464 . free .
4. Rak A, Pylypenko O, Niculae A, Goody RS, Alexandrov K . Crystallization and preliminary X-ray diffraction analysis of monoprenylated Rab7 GTPase in complex with Rab escort protein 1 . J. Struct. Biol. . 141 . 1 . 93–5 . Jan 2003 . 12576024 . 10.1016/S1047-8477(02)00634-2 .
5. Alexandrov K, Simon I, Iakovenko A, Holz B, Goody RS, Scheidig AJ . 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 . Apr 1998 . 9563513 . 10.1016/S0014-5793(98)00290-7 . 39125409 . free .
6. Pereira-Leal JB, Strom M, Godfrey RF, Seabra MC . Structural determinants of Rab and Rab Escort Protein interaction: Rab family motifs define a conserved binding surface . Biochem. Biophys. Res. Commun. . 301 . 1 . 92–7 . Jan 2003 . 12535645 . 10.1016/S0006-291X(02)02963-7 .