1l4s
From Proteopedia
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Solution structure of ribosome associated factor Y
Overview
Escherichia coli protein Y (pY) binds to the small ribosomal subunit and, stabilizes ribosomes against dissociation when bacteria experience, environmental stress. pY inhibits translation in vitro, most probably by, interfering with the binding of the aminoacyl-tRNA to the ribosomal A, site. Such a translational arrest may mediate overall adaptation of cells, to environmental conditions. We have determined the 3D solution structure, of a 112-residue pY and have studied its backbone dynamic by NMR, spectroscopy. The structure has a betaalphabetabetabetaalpha topology and, represents a compact two-layered sandwich of two nearly parallel alpha, helices packed against the same side of a four-stranded beta sheet. The 23, C-terminal residues of the protein are disordered. Long-range angular, constraints provided by residual dipolar coupling data proved critical for, precisely defining the position of helix 1. Our data establish that the, C-terminal region of helix 1 and the loop linking this helix with strand, beta2 show significant conformational exchange in the ms- micro s time, scale, which may have relevance to the interaction of pY with ribosomal, subunits. Distribution of the conserved residues on the protein surface, highlights a positively charged region towards the C-terminal segments of, both alpha helices, which most probably constitutes an RNA binding site., The observed betaalphabetabetabetaalpha topology of pY resembles the, alphabetabetabetaalpha topology of double-stranded RNA-binding domains, despite limited sequence similarity. It appears probable that functional, properties of pY are not identical to those of dsRBDs, as the postulated, RNA-binding site in pY does not coincide with the RNA-binding surface of, the dsRBDs.
About this Structure
1L4S is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Ribosome-associated factor Y adopts a fold resembling a double-stranded RNA binding domain scaffold., Ye K, Serganov A, Hu W, Garber M, Patel DJ, Eur J Biochem. 2002 Nov;269(21):5182-91. PMID:12392550
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