|
Advertisement | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
J. Biol. Chem., Vol. 277, Issue 9, 7108-7117, March 1, 2002
From the Department of Microbiology, University of Alabama at
Birmingham, Birmingham, Alabama 35294-4400
The cellular nuclear transport machinery relies
on the assembly of specialized transport complexes between soluble
transport receptors, transport substrates, and additional accessory
proteins. This study focuses on the structural characteristics of
influenza virus protein NS2 (NEP), which interacts with the nuclear
export machinery during viral replication, and has been proposed to act as an adapter molecule between the nuclear export machinery and the
viral ribonucleoprotein complex. For this purpose, we have purified
recombinant NS2 under nondenaturing conditions, and have investigated
its structure and aggregation state using optical spectroscopy,
differential scanning calorimetry, as well as hydrodynamic techniques.
Our results indicate that isolated NS2 exists as a monomer in solution,
and adopts a compact, but very flexible conformation, which shows
characteristics of the molten globule state under near physiological
conditions. Proteolytic sensitivity suggests that, despite its overall
plasticity, the structure of NS2 is heterogeneous. While the C terminus
of the protein adopts a relatively rigid conformation, its N terminus,
which is recognized by the nuclear export machinery, exists in a highly
mobile and exposed state. It is proposed that the flexibility observed
in the nuclear export domain of NS2 is an important element in the
recognition of substrate proteins by the nuclear export machinery.
To whom correspondence should be addressed. Tel.: 205-934-4259;
Fax: 205-934-0480; E-mail: ming@cmc.uab.edu.
Copyright © 2002 by The American Society for Biochemistry and Molecular Biology, Inc. This article has been cited by other articles:
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Advertisement | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||