title: Solution structure of a tethered Lmo2(LIM2) /Ldb1(LID)  complex.
abstract: LIM-only protein 2, Lmo2, is a regulatory protein that is essential for hematopoietic development and inappropriate overexpression of Lmo2 in T-cells contributes to T-cell leukemia. It exerts its functions by mediating protein-protein interactions and nucleating multicomponent transcriptional complexes. Lmo2 interacts with LIM domain binding protein 1 (Ldb1) through the tandem LIM domains of Lmo2 and the LIM interaction domain (LID) of Ldb1. Here, we present the solution structure of the LIM2 domain of Lmo2 bound to Ldb1(LID) . The ordered regions of Ldb1 in this complex correspond well with binding hotspots previously defined by mutagenic studies. Comparisons of this Lmo2(LIM2) -Ldb1(LID)  structure with previously determined structures of the Lmo2/Ldb1(LID)  complexes lead to the conclusion that modular binding of tandem LIM domains in Lmo2 to tandem linear motifs in Ldb1 is accompanied by several disorder-to-order transitions and/or conformational changes in both proteins.
authors.affiliation: School of Molecular Bioscience, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: Siavoush
authors.initials: S
authors.lastname: Dastmalchi
authors.forename: Lorna
authors.initials: L
authors.lastname: Wilkinson-White
authors.forename: Ann H
authors.initials: AH
authors.lastname: Kwan
authors.forename: Roland
authors.initials: R
authors.lastname: Gamsjaeger
authors.forename: Joel P
authors.initials: JP
authors.lastname: Mackay
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Matthews
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D060588:LIM Domain Proteins / Q000737:chemistry* / Q000378:metabolism; D051379:Mice; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; D060588:LIM Domain Proteins; C102084:Ldb1 protein, mouse; C513188:Lmo2 protein, mouse; D011994:Recombinant Proteins