Title: Crystallization and Preliminary X-Ray Analysis of the Splice Variant of Human Ankyrin Repeat and Suppressor of Cytokine Signaling Box Protein 9 (hASB9-2)
VOLUME: 16 ISSUE: 3
Author(s):Xiangwei Fei, Yong Zhang, Xing Gu, Rui Qiu, Yumin Mao and Chaoneng Ji
Affiliation:State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, Peoples Republic of China.
Keywords:hASB9, hASB9-2, ankyrin repeat, crystallization, preliminary X-ray analysis
Abstract: Human ankyrin repeat and suppressor of cytokine signaling box protein 9 (hASB9), a subunit of an Elongin Ccullin- SOCS box (ECS) E3 ubiquitin ligase complex, is believed to be involved in specific substrate-recognition for ubiquitination and degradation. In fact, this specific substrate-recognition is determined by the ankyrin repeats of hASB9 protein. Here, we have cloned and overexpressed the hASB9-2, the splice variant of hASB9 with only one ankyrin repeat domain, as a 6His-tagged recombinant protein in Escherichia coli. The purified hASB9-2 protein was crystallized by the hanging-drop vapor-diffusion technique and diffracted to 2.2Å resolution. The data showed that the cubic hASB9-2 crystal belongs to space group P4332 with unit-cell parameters (a=b=c=129.25Å, α=β=γ=90°). An asymmetric unit in the crystal was assumed to contain one protein molecule giving the Matthews Coefficient factor of 2.81 and the solvent content of 56.3%.
