Purification, crystallization and preliminary X-ray analysis of a fusion of the LIM domains of LMO2 and the LID domain of Ldb1.
LMO2 (LIM domain only 2), also known as rhombotin-2, is a transcriptional regulator that is essential for normal haematopoietic development. In malignant haematopoiesis, its ectopic expression in T cells is involved in the pathogenesis of leukaemia. LMO2 contains four zinc-finger domains and binds to the ubiquitous nuclear adaptor protein Ldb1 via the LIM-interaction domain (LID). Together, they act as scaffolding proteins and bridge important haematopoietic transcription factors such as SCL/Tal1, E2A and GATA-1. Solving the structure of the LMO2:Ldb1-LID complex would therefore be a first step towards understanding how haematopoietic specific protein complexes form and would also provide an attractive target for drug development in anticancer therapy, especially for T-cell leukaemia. Here, the expression, purification, crystallization and data collection of a fusion protein consisting of the two LIM domains of LMO2 linked to the LID domain of Ldb1 via a flexible linker is reported. The crystals belonged to space group C2, with unit-cell parameters a = 179.9, b = 51.5, c = 114.7 Å, β = 90.1°, and contained five molecules in the asymmetric unit. Multiple-wavelength anomalous dispersion (MAD) data have been collected at the zinc X-ray absorption edge to a resolution of 2.8 Å and the data were used to solve the structure of the LMO2:Ldb1-LID complex. Refinement and analysis of the electron-density map is in progress.
Division of Structural Biology, The Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, England.
Kamel
K
El Omari
Catherine
C
Porcher
Erika J
EJ
Mancini
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000302:isolation & purification; D006801:Humans; D060588:LIM Domain Proteins; D008667:Metalloproteins / Q000737:chemistry* / Q000302:isolation & purification; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors / Q000737:chemistry* / Q000302:isolation & purification
D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; D060588:LIM Domain Proteins; C085117:LMO2 protein, human; D008667:Metalloproteins; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors