Acta Crystallographica Section D

Biological Crystallography

Volume 69, Part 12 (December 2013)

research papers

Acta Cryst. (2013). D69, 2495-2505    [ doi:10.1107/S0907444913023354 ]

Phosphorylation adjacent to the nuclear localization signal of human dUTPase abolishes nuclear import: structural and mechanistic insights

G. Róna, M. Marfori, M. Borsos, I. Scheer, E. Takács, J. Tóth, F. Babos, A. Magyar, A. Erdei, Z. Bozóky, L. Buday, B. Kobe and B. G. Vértessy

Abstract: Phosphorylation adjacent to nuclear localization signals (NLSs) is involved in the regulation of nucleocytoplasmic transport. The nuclear isoform of human dUTPase, an enzyme that is essential for genomic integrity, has been shown to be phosphorylated on a serine residue (Ser11) in the vicinity of its nuclear localization signal; however, the effect of this phosphorylation is not yet known. To investigate this issue, an integrated set of structural, molecular and cell biological methods were employed. It is shown that NLS-adjacent phosphorylation of dUTPase occurs during the M phase of the cell cycle. Comparison of the cellular distribution of wild-type dUTPase with those of hyperphosphorylation- and hypophos­phorylation-mimicking mutants suggests that phosphorylation at Ser11 leads to the exclusion of dUTPase from the nucleus. Isothermal titration microcalorimetry and additional independent biophysical techniques show that the interaction between dUTPase and importin-[alpha], the karyopherin molecule responsible for `classical' NLS binding, is weakened significantly in the case of the S11E hyperphosphorylation-mimicking mutant. The structures of the importin-[alpha]-wild-type and the importin-[alpha]-hyperphosphorylation-mimicking dUTPase NLS complexes provide structural insights into the molecular details of this regulation. The data indicate that the post-translational modification of dUTPase during the cell cycle may modulate the nuclear availability of this enzyme.

PDB references: 4mz5 and 4mz6

Keywords: nuclear import; phosphorylation; nuclear localization signal; dUTPase; importin.

pdfdisplay filedownload file

Portable Document Format (PDF) file (3353.6 kbytes)
[ doi:10.1107/S0907444913023354/dw5062sup1.pdf ]
Supplementary material


To open or display or play some files, you may need to set your browser up to use the appropriate software. See the full list of file types for an explanation of the different file types and their related mime types and, where available links to sites from where the appropriate software may be obtained.

The download button will force most browsers to prompt for a file name to store the data on your hard disk.

Where possible, images are represented by thumbnails.

 bibliographic record in  format

  Find reference:   Volume   Page   
  Search:     From   to      Advanced search

Copyright © International Union of Crystallography
IUCr Webmaster