Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
2001-4-24
pubmed:databankReference
pubmed:abstractText
Rab GTPases function as regulatory components of an evolutionarily conserved machinery that mediates docking, priming, and fusion of vesicles with intracellular membranes. We have previously shown that the active conformation of Rab3A is stabilized by a substantial hydrophobic interface between the putative conformational switch regions (Dumas, J. J., Zhu, Z., Connolly, J. L., and Lambright, D. G. (1999) Structure 7, 413-423). A triad of invariant hydrophobic residues at this switch interface (Phe-59, Trp-76, and Tyr-91) represents a major interaction determinant between the switch regions of Rab3A and the Rab3A-specific effector Rabphilin3A (Ostermeier, C., and Brunger, A. T. (1999) Cell 96, 363-374). Here, we report the crystal structure of the active form of Rab5C, a prototypical endocytic Rab GTPase. As is true for Rab3A, the active conformation of Rab5C is stabilized by a hydrophobic interface between the switch regions. However, the conformation of the invariant hydrophobic triad (residues Phe-58, Trp-75, and Tyr-90 in Rab5C) is dramatically altered such that the resulting surface is noncomplementary to the switch interaction epitope of Rabphilin3A. This structural rearrangement reflects a set of nonconservative substitutions in the hydrophobic core between the central beta sheet and the alpha2 helix. These observations demonstrate that structural plasticity involving an invariant hydrophobic triad at the switch interface contributes to the mechanism by which effectors recognize distinct Rab subfamilies. Thus, the active conformation of the switch regions conveys information about the identity of a particular Rab GTPase as well as the state of the bound nucleotide.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Adaptor Proteins, Signal Transducing, http://linkedlifedata.com/resource/pubmed/chemical/Epitopes, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Phenylalanine, http://linkedlifedata.com/resource/pubmed/chemical/RAB5C protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Tryptophan, http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine, http://linkedlifedata.com/resource/pubmed/chemical/Vesicular Transport Proteins, http://linkedlifedata.com/resource/pubmed/chemical/rab GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/rab3A GTP-Binding Protein, http://linkedlifedata.com/resource/pubmed/chemical/rab5 GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/rabphilin-3A
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13982-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11278565-Adaptor Proteins, Signal Transducing, pubmed-meshheading:11278565-Amino Acid Sequence, pubmed-meshheading:11278565-Base Sequence, pubmed-meshheading:11278565-Crystallography, X-Ray, pubmed-meshheading:11278565-Epitopes, pubmed-meshheading:11278565-Escherichia coli, pubmed-meshheading:11278565-Models, Molecular, pubmed-meshheading:11278565-Molecular Sequence Data, pubmed-meshheading:11278565-Nerve Tissue Proteins, pubmed-meshheading:11278565-Phenylalanine, pubmed-meshheading:11278565-Protein Binding, pubmed-meshheading:11278565-Protein Conformation, pubmed-meshheading:11278565-Protein Structure, Secondary, pubmed-meshheading:11278565-Protein Structure, Tertiary, pubmed-meshheading:11278565-Tryptophan, pubmed-meshheading:11278565-Tyrosine, pubmed-meshheading:11278565-Vesicular Transport Proteins, pubmed-meshheading:11278565-rab GTP-Binding Proteins, pubmed-meshheading:11278565-rab3A GTP-Binding Protein, pubmed-meshheading:11278565-rab5 GTP-Binding Proteins
pubmed:year
2001
pubmed:articleTitle
Structural plasticity of an invariant hydrophobic triad in the switch regions of Rab GTPases is a determinant of effector recognition.
pubmed:affiliation
Program in Molecular Medicine and Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester 01605, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.