title: Ligand-dependent dynamics and intramolecular signaling in a PDZ domain.
abstract: Allosteric communication is a fundamental process that proteins use to propagate signals from one site to functionally important distal sites. Although allostery is usually associated with multimeric proteins and enzymes, "long-range" communication may be a fundamental property of proteins. In some cases, communication occurs with minimal structural change. PDZ (post-synaptic density-95/discs large/zonula occludens-1) domains are small, protein-protein binding modules that can use multiple surfaces for docking diverse molecules. Furthermore, these domains have long-range energetic couplings that link the ligand-binding site to distal regions of the structure. Here, we show that allosteric behavior in a representative member of the PDZ domain family may be directly detected using side-chain methyl dynamics measurements. The changes in side-chain dynamics parameters in the second PDZ domain from the human tyrosine phosphatase 1E (hPTP1E) were determined upon binding a peptide target. Long-range dynamic effects were detected that correspond to previously observed pair-wise energetic couplings. These results provide one of the first experimental examples for the potential role of ps-ns timescale dynamics in propagating long-range signals within a protein, and reinforce the idea that dynamic fluctuations in proteins contribute to allosteric signal transduction.
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: Ernesto J
authors.initials: EJ
authors.lastname: Fuentes
authors.forename: Channing J
authors.initials: CJ
authors.lastname: Der
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Lee
mesh_terms: D000494:Allosteric Regulation; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D006801:Humans; D008024:Ligands; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction; D013816:Thermodynamics
chemical_list: D008024:Ligands; D010455:Peptides; D017027:Protein Tyrosine Phosphatases