Multiple vesiculoviral matrix proteins inhibit both nuclear export and import

doi:10.1073/pnas.151240998

Multiple vesiculoviral matrix proteins inhibit both nuclear export and import

Department of Biomolecular Chemistry, University of Wisconsin, Madison, WI 53706-1532

Contributed by James E. Dahlberg

Abstract

The matrix (M) protein of vesicular stomatitis virus inhibits both nuclear import and export. Here, we demonstrate that this inhibitory property is conserved between the M proteins from two other vesiculoviruses, chandipura virus and spring viremia carp virus. All three M proteins completely block nuclear transport of spliced mRNA, small nuclear RNAs, and small nuclear ribonucleoproteins and slow the nuclear transport of many other cargoes. In all cases where transport was merely slowed by the M proteins, the chandipura virus M protein had the strongest inhibitory activity. When expressed in transfected HeLa cells, active M proteins displayed prominent association with the nuclear rim. Moreover, mutation of a conserved methionine abolished both the inhibitory activity and efficient targeting of the M proteins to the nuclear rim. We propose that all of the vesiculoviral M proteins associate with the same nuclear target, which is likely to be a component of the nuclear pore complex.

Footnotes

↵ * Present address: Bacterial Zoonoses Branch, Division of Vector-Borne Infectious Diseases, Centers for Disease Control, 1300 Rampart Road, Ft. Collins, CO 80521.
↵ † To whom reprint requests should be addressed. E-mail: dahlberg{at}facstaff.wisc.edu.
Abbreviations:

NPC,

nuclear pore complex;

snRNA,

small nuclear RNA;

VSV,

vesicular stomatitis virus;

snRNP,

small nuclear ribonucleoprotein;

GFP,

green fluorescent protein;

CV,

chandipura virus;

SVCV,

spring viremia carp virus;

GST,

glutathione S-transferase;

PV,

piry virus;

CTE,

constitutive transport element;

NLS,

nuclear localization signal;

M protein,

matrix protein;

NP,

nucleoplasmin