The pentameric nucleoplasmin fold is present in Drosophila FKBP39 and a large number of chromatin-related proteins.
Bottom Line: The pentameric core domain, a doughnut-like structure with a central pore, is only found in the nucleoplasmin family.Furthermore, we show that two other chromatin proteins, Arabidopsis thaliana histone deacetylase type 2 (HD2) and Saccharomyces cerevisiae Fpr4, share the NPL fold and form pentamers, or a dimer of pentamers in the case of HD2.Thus, we propose a new family of proteins that share the pentameric nucleoplasmin-like NPL domain and are found in protists, fungi, plants and animals.
Affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, CB2 1GA Cambridge, United Kingdom.Show MeSH
Mentions: Size-exclusion chromatography gave an early indication that the NPL domain forms an oligomer, and the apparent molecular weight was consistent with the formation of a nucleoplasmin-like pentamer. In order to test this hypothesis, we studied deuterated NPL using small-angle neutron scattering (SANS). The SANS scattering profile matched a protein of about 50 kDa and produced an excellent fit when modelled with 5-fold symmetry. Modelling with a 6-fold symmetry did not fit the data so well. A bead model was constructed from the scattering profile (Fig. 3), and this clearly shows a doughnut-shaped structure that matches the dimensions of the nucleoplasmin pentamer.
Affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, CB2 1GA Cambridge, United Kingdom.