Preliminary X-ray crystallographic studies of the short form of the human TRAF4 TRAF domain

Abstract

TNF (tumour necrosis factor) receptor-associated factor 4 (TRAF4) is a unique TRAF protein that participates in morphogenetic and developmental function and cell migration. TRAF-family proteins contain a TRAF domain for target interaction. In this study, the short form of the human TRAF4 TRAF domain, corresponding to amino acids 290-462, was overexpressed in Escherichia coli using engineered C-terminal His tags. The short form of the TRAF4 TRAF domain was purified to homogeneity and crystallized at 293 K. Finally, X-ray diffraction data were collected to a resolution of 4.2 Å from a crystal belonging to the hexagonal space group P3₂, with unit-cell parameters a = b = 147.17, c = 202.69 Å.

Keywords: TRAF4 TRAF domain.

Figure 1

Purification of a short form of the TRAF4 TRAF domain. (a) The typical trimeric mushroom-like structure of the TRAF domain. The TRAF5 TRAF domain is shown as a representative structure (PDB entry 4gjh; Zhang et al., 2012 ▶). (b) Gel-filtration chromatography profile. An SDS–PAGE of the peak fractions is shown.

Figure 2

Crystals of a short form of the human TRAF4 TRAF domain. Crystals were grown in 7 d in the presence of 1.2 M lithium sulfate monohydrate, 0.01 M nickel chloride hexahydrate, 0.1 M Tris–HCl pH 8.2. The approximate dimensions of the crystals were 0.5 × 0.2 × 0.1 mm.

Figure 3

Diffraction image (1° oscillation) of a crystal of a short form of the TRAF4 TRAF domain with a 4.2 Å resolution limit.