Purification, crystallization and preliminary X-ray analysis of a fusion of the LIM domains of LMO2 and the LID domain of Ldb1.

Journal article

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.

Authors: El Omari, K; Porcher, C; Mancini, E

• Publication status: Published
• Journal: Acta crystallographica. Section F, Structural biology and crystallization communications
• Volume: 66
• Issue: Pt 11
• Pages: 1466-1469
• Publication date: 2010-11-01
• DOI: 10.1107/s1744309110032872
• EISSN: 1744-3091
• ISSN: 1744-3091
• Language: English
• Keywords: Humans; Crystallization; Proto-Oncogene Proteins; Metalloproteins; Crystallography, X-Ray; LIM Domain Proteins; DNA-Binding Proteins; Adaptor Proteins, Signal Transducing; Amino Acid Sequence; Transcription Factors