Retinal degeneration in choroideremia: deficiency of rab geranylgeranyl transferase

Science. 1993 Jan 15;259(5093):377-81. doi: 10.1126/science.8380507.


Rab geranylgeranyl transferase (GG transferase) is a two-component enzyme that attaches 20-carbon isoprenoid groups to cysteine residues in Rab proteins, a family of guanosine triphosphate-binding proteins that regulate vesicular traffic. The mutant gene in human choroideremia, an X-linked form of retinal degeneration, encodes a protein that resembles component A of rat Rab GG transferase. Lymphoblasts from choroideremia subjects showed a marked deficiency in the activity of component A, but not component B, of Rab GG transferase. The deficiency was more pronounced when the substrate was Rab3A, a synaptic vesicle protein, than it was when the substrate was Rab1A, a protein of the endoplasmic reticulum. The data imply the existence of multiple component A proteins, one of which is missing in choroideremia.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Alkyl and Aryl Transferases*
  • Cell Line, Transformed
  • Cells, Cultured
  • Choroid / chemistry
  • Choroideremia / genetics*
  • Female
  • GTP-Binding Proteins / analysis
  • GTP-Binding Proteins / metabolism*
  • Gene Expression Regulation, Enzymologic
  • Humans
  • Lymphocyte Activation
  • Male
  • Middle Aged
  • Mutation
  • Nerve Tissue Proteins / analysis
  • Nerve Tissue Proteins / metabolism*
  • Photoreceptor Cells / chemistry
  • Pigment Epithelium of Eye / chemistry
  • Protein Prenylation
  • Retina / chemistry
  • Substrate Specificity
  • Transferases / deficiency*
  • Transferases / genetics
  • rab1 GTP-Binding Proteins
  • rab3 GTP-Binding Proteins


  • Nerve Tissue Proteins
  • Transferases
  • Alkyl and Aryl Transferases
  • Rab geranylgeranyltransferase
  • GTP-Binding Proteins
  • rab1 GTP-Binding Proteins
  • rab3 GTP-Binding Proteins