Newcastle Disease Virus Replication. In: Alexander DJ, editor. Newcastle Disease. Boston: Springer US; 1988. pp. 45-78. [DOI: 10.1007/978-1-4613-1759-3_4]

Characterization of nucleocapsid and matrix proteins of Newcastle disease virus in yeast

Newcastle disease virus is a member of family Paramyxoviridae that infects chicken. Its genome comprises ~15.2 kb negative-sense RNA that encodes six major proteins. The virus encodes various proteins; among all, nucleocapsid (NP) and matrix (M) help in virus replication and its budding from the host cells, respectively. In this study, we investigated the intracellular distribution of NP and M upon expression in the yeast Saccharomyces cerevisiae. We observed nuclear targeting of M, and vacuolar localization of NP was observed in a fraction of yeast cells. Prolonged expression of GFP fused NP or M resulted in altered cell viability and intracellular production of reactive oxygen species in yeast cells. The expression of viral proteins did not alter the morphology and number of the organelles such as nucleus, mitochondria, endoplasmic reticulum, and peroxisomes. However, a significant effect was observed on vacuolar morphology and number in yeast cells. These observations point towards the importance of host cellular reorganization in viral infection. These findings may enable us to understand the conserved pathways affected in eukaryotic cells as a result of viral protein expression.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-020-02624-4.

Newcastle disease virus: macromolecules and opportunities

Over the past two decades, enormous advances have occurred in the structural and biological characterization of Newcastle disease virus (NDV). As a result, not only the complete sequence of the viral genome has been fully determined, but also a clearer understanding of the viral proteins and their respective roles in the life cycle has been achieved. This article reviews the progress in the molecular biology of NDV with emphasis on the new technologies. It also identifies the fundamental problems that need to be addressed and attempts to predict some research opportunities in NDV that can be realized in the near future for the diagnosis, prevention and treatment of disease(s).

High-level expression of a foreign gene from the most 3'-proximal locus of a recombinant Newcastle disease virus

A previous report showed that insertion of a foreign gene encoding chloramphenicol acetyltransferase (CAT) between the HN and L genes of the full-length cDNA of a virulent Newcastle disease virus (NDV) yielded virus with growth retardation and attenuation. The NDV vector used in that study was pathogenic to chickens; it is therefore not suitable for use as a vaccine vector. In the present study, an avirulent NDV vector was generated and its potential to express CAT protein was evaluated. The CAT gene was under the control of NDV transcriptional start and stop signals and was inserted immediately before the open reading frame of the viral 3'-proximal nucleocapsid protein gene. A recombinant NDV expressing CAT activity at a high level was recovered. The replication and pathogenesis of the CAT-expressing recombinant NDV were not modified significantly. These results indicate the potential utility of an avirulent NDV as a vaccine vector.

Structure, function, and intracellular processing of paramyxovirus membrane proteins

Paramyxoviruses are a fascinating group of viruses with diverse hosts and disease manifestations. They are valuable systems for studying viral pathogenesis, molecular mechanisms of negative strand viral replication, and glycoprotein structure and function. In the past few years this group of viruses has received increased attention and as a result there is a wealth of new information. For example, most of the genes of many paramyxoviruses have been cloned and sequenced. The recent availability of sequence information from a number of paramyxoviruses now allows the direct comparison of the amino acid sequence and determinants of secondary structure of analogous genes across the family of viruses. Such comparisons are revealing for two reasons. First, results provide clues to the evolution of these viruses. Second, and more importantly, comparisons of analogous genes may point to sequences and structural determinants that are central to the function of the individual proteins. Below is a comparison of five of the paramyxovirus genes with a discussion of the implications of common structural determinants for function, intracellular processing, and evolutionary origin. The focus is on the paramyxovirus membrane proteins, although other proteins are discussed briefly.