title: Rab GTPase prenylation hierarchy and its potential role in choroideremia disease.
abstract: Protein prenylation is a widespread post-translational modification in eukaryotes that plays a crucial role in membrane targeting and signal transduction. RabGTPases is the largest group of post-translationally C-terminally geranylgeranylated. All Rabs are processed by Rab geranylgeranyl-transferase and Rab escort protein (REP). Human genetic defects resulting in the loss one of two REP isoforms REP-1, lead to underprenylation of RabGTPases that manifests in retinal degradation and blindness known as choroideremia. In this study we used a combination of microinjections and chemo-enzymatic tagging to establish whether Rab GTPases are prenylated and delivered to their target cellular membranes with the same rate. We demonstrate that although all tested Rab GTPases display the same rate of membrane delivery, the extent of Rab prenylation in 5 hour time window vary by more than an order of magnitude. We found that Rab27a, Rab27b, Rab38 and Rab42 display the slowest prenylation in vivo and in the cell. Our work points to possible contribution of Rab38 to the emergence of choroideremia in addition to Rab27a and Rab27b.
authors.affiliation: Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia.
authors.forename: Monika
authors.initials: M
authors.lastname: Köhnke
authors.affiliation: Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Delon
authors.affiliation: Queensland Berghofer Medical Research Institute, PO Royal Brisbane Hospital, Herston, Queensland, Australia.
authors.forename: Marcus L
authors.initials: ML
authors.lastname: Hastie
authors.affiliation: Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia.
authors.forename: Uyen T T
authors.initials: UT
authors.lastname: Nguyen
authors.affiliation: Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany.
authors.forename: Yao-Wen
authors.initials: YW
authors.lastname: Wu
authors.affiliation: Department of Chemical Biology, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Waldmann
authors.affiliation: Department of Physical Biochemistry, Max-Planck-Institute for Molecular Physiology, Dortmund, Germany.
authors.forename: Roger S
authors.initials: RS
authors.lastname: Goody
authors.affiliation: Queensland Berghofer Medical Research Institute, PO Royal Brisbane Hospital, Herston, Queensland, Australia.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Gorman
authors.affiliation: Department of Cell and Molecular Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia.
authors.forename: Kirill
authors.initials: K
authors.lastname: Alexandrov
mesh_terms: D015794:Choroideremia / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli; D006801:Humans; D054876:Prenylation; D013997:Time Factors; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D020691:rab GTP-Binding Proteins