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: The phylogenetic tree of NPL sequences from plants, fungi and animals (Fig. 1) clearly shows that NPL-FKBPs and HD-tuins form their own well-separated clades. However, the major divide is between nucleoplasmins and the other two groups, with as little as 12% pairwise sequence identity between them. This can also be observed in the sequence alignment (Fig. 2) where only the hydrophobic character of some residues and the position of the β-strands are preserved between Xenopus nucleoplasmin (third to the last sequence in the alignment) and all the other proteins. In order to investigate whether all of these sequences share a common three-dimensional fold, we set out to determine the structure of a non-nucleoplasmin NPL.
Affiliation: Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, CB2 1GA Cambridge, United Kingdom.