The 1.6 angstrom resolution crystal structure of nuclear transport factor 2 (NTF2)

Nuclear transport factor 2 (NTF2) facilitates protein transport into the nucleus and interacts with both the small Ras-like GTPase Ran and nucleoporin p62. We have determined the structure of bacterially expressed rat NTF2 at 1.6 Angstrom resolution using X-ray crystallography. The NTF2 poly-peptide chain forms an alpha+beta barrel that opens at one end to form a distinctive hydrophobic cavity and its fold is homologous to that of scytalone dehydratase. The NTF2 hydrophobic cavity is a candidate for a potential binding site for other proteins involved in nuclear import such as Ran and nucleoporin p62, In addition, the hydrophobic cavity contains a putative catalytic Asp-His pair, which raises the possibility of an unanticipated enzymatic activity of the molecule that may have implications far the molecular mechanism of nuclear protein import. (C) 1996 Academic Press Limited