Affiliation:
1. Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
2. Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA
Abstract
ABSTRACT
The Newcastle disease virus (NDV) fusion protein (F) mediates fusion of viral and host cell membranes and is a major determinant of NDV pathogenicity. In the present study, we demonstrate the effects of functional properties of F cytoplasmic tail (CT) amino acids on virus replication and pathogenesis. Out of a series of C-terminal deletions in the CT, we were able to rescue mutant viruses lacking two or four residues (rΔ2 and rΔ4). We further rescued viral mutants with individual amino acid substitutions at each of these four terminal residues (rM553A, rK552A, rT551A, and rT550A). In addition, the NDV F CT has two conserved tyrosine residues (Y524 and Y527) and a dileucine motif (LL536-537). In other paramyxoviruses, these residues were shown to affect fusion activity and are central elements in basolateral targeting. The deletion of 2 and 4 CT amino acids and single tyrosine substitution resulted in hyperfusogenic phenotypes and increased viral replication and pathogenesis. We further found that in rY524A and rY527A viruses, disruption of the targeting signals did not reduce the expression on the apical or basolateral surface in polarized Madin-Darby canine kidney cells, whereas in double tyrosine mutant, it was reduced on both the apical and basolateral surfaces. Interestingly, in rL536A and rL537A mutants, the F protein expression was more on the apical than on the basolateral surface, and this effect was more pronounced in the rL537A mutant. We conclude that these wild-type residues in the NDV F CT have an effect on regulating F protein biological functions and thus modulating viral replication and pathogenesis.
Publisher
American Society for Microbiology
Subject
Virology,Insect Science,Immunology,Microbiology
Reference61 articles.
1. Newcastle disease and other avian paramyxovirus
2. SamalSK. 2011. Newcastle disease and related avian paramyxoviruses, p 69–114. In SamalSK (ed), The biology of paramyxoviruses. Caister Academic Press, Norfolk, United Kingdom.
3. Detection and differentiation of Newcastle disease virus (avian paramyxovirus type 1);Aldous EW;Avian Pathol.,2001
4. LambRA KolakofskyD. 2001. Paramyxoviridae: the viruses and their replication, p 1305–1340. In KnipeDM HowleyPM (ed), Fields virology. Lippincott Williams & Wilkins, Philadelphia, PA.
5. The structure of the fusion glycoprotein of Newcastle disease virus suggests a novel paradigm for the molecular mechanism of membrane fusion;Chen L;Structure,2001
Cited by
26 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献