Crystallization and preliminary X-ray crystallographic studies of the CARD domain of human CARMA1

The CARMA1 signalosome, which is composed of CARMA1 [caspase recruitment domain (CARD) containing MAGUK protein 1], BCL10 (B-cell lymphoma 10) and MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1), is a molecular-signalling complex that performs pivotal functions in T-cell receptor (TCR) and B-cell receptor (BCR) mediated NF-κB activation. In this study, the CARD domain of human CARMA1 (CARMA1 CARD), corresponding to amino acids 14-109, was overexpressed in Escherichia coli using an engineered C-terminal His tag. CARMA1 CARD was then purified to homogeneity and crystallized at 293 K. Finally, X-ray diffraction data were collected to a resolution of 3.2 Å from a crystal belonging to space group P2(1)2(1)2(1) with unit-cell parameters a = 45.73, b = 53.37, c = 91.89 Å.