Download MendeleyCrystal structure of the oligomerization domain of NSP4 from rotavirus reveals a core metal-binding site.
Bowman, G.D., Nodelman, I.M., Levy, O., Lin, S.L., Tian, P., Zamb, T.J., Udem, S.A., Venkataraghavan, B., Schutt, C.E.(2000) J Mol Biol 304: 861-871
- PubMed: 11124032
- DOI: https://doi.org/10.1006/jmbi.2000.4250
- Primary Citation of Related Structures:
1G1I, 1G1J - PubMed Abstract:
During the maturation of rotaviral particles, non-structural protein 4 (NSP4) plays a critical role in the translocation of the immature capsid into the lumen of the endoplasmic reticulum. Full-length NSP4 and a 22 amino acid peptide (NSP4(114-135)) derived from this protein have been shown to induce diarrhea in young mice in an age-dependent manner, and may therefore be the agent responsible for rotavirally-induced symptoms. We have determined the crystal structure of the oligomerization domain of NSP4 which spans residues 95 to 137 (NSP4(95-137)). NSP4(95-137) self-associates into a parallel, tetrameric coiled-coil, with the hydrophobic core interrupted by three polar layers occupying a and d-heptad positions. Side-chains from two consecutive polar layers, consisting of four Gln123 and two of the four Glu120 residues, coordinate a divalent cation. Two independent structures built from MAD-phased data indicated the presence of a strontium and calcium ion bound at this site, respectively. This metal-binding site appears to play an important role in stabilizing the homo-tetramer, which has implications for the engagement of NSP4 as an enterotoxin.
Organizational Affiliation:
Department of Molecular Biology, Lewis Thomas Laboratories, Princeton University, Princeton, NJ 08544, USA.
