Structure of nucleophosmin DNA-binding domain and analysis of its complex with a G-quadruplex sequence from the c-MYC promoter.

Nucleophosmin (NPM1) is a nucleocytoplasmic shuttling protein, mainly localized at nucleoli, that plays a key role in several cellular functions, including ribosome maturation and export, centrosome duplication, and response to stress stimuli. More than 50 mutations at the terminal exon of the NPM1 gene have been identified so far in acute myeloid leukemia; the mutated proteins are aberrantly and stably localized in the cytoplasm due to high destabilization of the NPM1 C-terminal domain and the appearance of a new nuclear export signal. We have shown previously that the 70-residue NPM1 C-terminal domain (NPM1-C70) is able to bind with high affinity a specific region at the c-MYC gene promoter characterized by parallel G-quadruplex structure.

Sco proteins are involved in electron transfer processes.

Sco proteins are widespread in eukaryotic and in many prokaryotic organisms. They have a thioredoxin-like fold and bind a single copper(I) or copper(II) ion through a CXXXC motif and a conserved His ligand, with both tight and weak affinities. They have been implicated in the assembly of the Cu(A) site of cytochrome c oxidase as copper chaperones and/or thioredoxins.

Toward structural dynamics: protein motions viewed by chemical shift modulations and direct detection of C'N multiple-quantum relaxation.

Multiple quantum relaxation in proteins reveals unexpected relationships between correlated or anti-correlated conformational backbone dynamics in alpha-helices or beta-sheets. The contributions of conformational exchange to the relaxation rates of C'N coherences (i.e.

The solution structure of the monomeric copper, zinc superoxide dismutase from Salmonella enterica: structural insights to understand the evolution toward the dimeric structure.

The structure of the SodCII-encoded monomeric Cu, Zn superoxide dismutase from Salmonella enterica has been solved by NMR spectroscopy. This represents the first solution structure of a natural and fully active monomeric superoxide dismutase in solution, providing information useful for the interpretation of the evolutional development of these enzymes. The protein scaffold consists of the characteristic beta-barrel common to the whole enzyme family.

NMR assignment of reduced form of copper, zinc superoxide dismutase from Salmonella enterica.

Almost complete assignment (97%) of NMR resonances was obtained for the reduced, Cu(I), form of prokaryotic CuZnSOD from Salmonella enterica. 13C direct detection was used to complement the standard bouquet of 1H detected triple resonance experiments and contributed to the identification of proline backbone resonances and to side chains assignments of Asx, Glx and aromatic rings. This is the only complete assignment available for monomer SOD from prokaryotic organisms.