Rab escort protein 1

From Wikipedia, the free encyclopedia
AliasesCHM, DXS540, GGTA, HSD-32, REP-1, TCD, Rab escort protein 1, CHM Rab escort protein
External IDsOMIM: 300390 MGI: 892979 HomoloGene: 334 GeneCards: CHM
RefSeq (mRNA)


RefSeq (protein)


Location (UCSC)Chr X: 85.86 – 86.05 MbChr X: 111.95 – 112.1 Mb
PubMed search[3][4]
View/Edit HumanView/Edit Mouse

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.[5][6]


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.[6]


CHM (gene) has been shown to interact with RAB1A,[7] RAB7A[8][9] and RAB3A.[7][10]

Clinical significance[edit]

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.[6]

See also[edit]


  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000188419Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000025531Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ Molloy CM, van de Pol TJ, Brohet RM, Ropers HH, Cremers FP (May 1992). "Three RFLPs for pZ11 (DXS540) in the choroideremia gene at Xq21.2". Nucleic Acids Res. 20 (6): 1434. doi:10.1093/nar/20.6.1434. PMC 312214. PMID 1373238.
  6. ^ a b c "Entrez Gene: CHM choroideremia (Rab escort protein 1)".
  7. ^ a b Cremers FP, Armstrong SA, Seabra MC, Brown MS, Goldstein JL (Jan 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.
  8. ^ Rak A, Pylypenko O, Niculae A, Goody RS, Alexandrov K (Jan 2003). "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. doi:10.1016/S1047-8477(02)00634-2. PMID 12576024.
  9. ^ Alexandrov K, Simon I, Iakovenko A, Holz B, Goody RS, Scheidig AJ (Apr 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.
  10. ^ Pereira-Leal JB, Strom M, Godfrey RF, Seabra MC (Jan 2003). "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. doi:10.1016/S0006-291X(02)02963-7. PMID 12535645.

Further reading[edit]

External links[edit]