Publication Abstract from PubMed
To achieve the greatest output from their limited genomes, viruses frequently make use of alternative open reading frames, in which translation is initiated from a start codon within an existing gene and, being out of frame, gives rise to a distinct protein product. These alternative protein products are, as yet, poorly characterized structurally. Here we report the crystal structure of ORF-9b, an alternative open reading frame within the nucleocapsid (N) gene from the SARS coronavirus. The protein has a novel fold, a dimeric tent-like beta structure with an amphipathic surface, and a central hydrophobic cavity that binds lipid molecules. This cavity is likely to be involved in membrane attachment and, in mammalian cells, ORF-9b associates with intracellular vesicles, consistent with a role in the assembly of the virion. Analysis of ORF-9b and other overlapping genes suggests that they provide snapshots of the early evolution of novel protein folds.
The crystal structure of ORF-9b, a lipid binding protein from the SARS coronavirus.,Meier C, Aricescu AR, Assenberg R, Aplin RT, Gilbert RJ, Grimes JM, Stuart DI Structure. 2006 Jul;14(7):1157-65. PMID:16843897[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
