Recent advances in the molecular and cellular biology of bunyaviruses

Abstract

The family Bunyaviridae of segmented, negative-stranded RNA viruses includes over 350 members that infect a bewildering variety of animals and plants. Many of these bunyaviruses are the causative agents of serious disease in their respective hosts, and are classified as emerging viruses because of their increased incidence in new populations and geographical locations throughout the world. Emerging bunyaviruses, such as Crimean-Congo hemorrhagic fever virus, tomato spotted wilt virus and Rift Valley fever virus, are currently attracting great interest due to migration of their arthropod vectors, a situation possibly linked to climate change. These and other examples of continued emergence suggest that bunyaviruses will probably continue to pose a sustained global threat to agricultural productivity, animal welfare and human health. The threat of emergence is particularly acute in light of the lack of effective preventative or therapeutic treatments for any of these viruses, making their study an important priority. This review presents recent advances in the understanding of the bunyavirus life cycle, including aspects of their molecular, cellular and structural biology. Whilst special emphasis is placed upon the emerging bunyaviruses, we also describe the extensive body of work involving model bunyaviruses, which have been the subject of major contributions to our overall understanding of this important group of viruses.

Expression, purification and crystallization of the Crimean–Congo haemorrhagic fever virus nucleocapsid protein

“…These differences are also highlighted by comparison with the similar-sized nucleocapsid of the hantaviruses, which has been proposed to form trimers as intermediates in RNP assembly (Kaukinen et al, 2004). Our data suggest that the CCHFV N protein may potentially utilize a dimeric intermediate for RNP formation and provides further evidence that bunyaviruses may not utilize a common strategy of RNP formation (Walter & Barr, 2011). From this structure, we hope to obtain insight into RNA binding, RNP formation and virus assembly.…”

“…All five genera contain species that impact on human health or welfare, either directly by causing disease or indirectly by impinging on the productivity of livestock or crop plants (Elliott, 2009). Classification into this family is based on the possession of a genome comprising three single-stranded RNA segments of either negative-sense or ambisense polarity, designated small (S), medium (M) and large (L) (Walter & Barr, 2011). Bunyavirus replication is confined to the cytoplasm of infected cells and virus particles are enveloped, with a diameter of approximately 80-120 nm.…”

A Glycoprotein Subunit Vaccine Elicits a Strong Rift Valley Fever Virus Neutralizing Antibody Response in Sheep

“…RVFV belongs to the genus Phlebovirus within the family Bunyaviridae, which includes over 350 named isolates (Walter and Barr 2011). It has a tripartite single-stranded RNA genome of negative polarity consisting of small (S), medium (M), and large (L) RNA segments.…”

Structure of the Leanyer orthobunyavirus nucleoprotein–RNA complex reveals unique architecture for RNA encapsidation

“…There are five genera in the Bunyaviridae family-Orthobunyavirus, Phlebovirus, Hantavirus, Nairovirus, and Tospovirus-of negative-sense ssRNA viruses that infect humans, animals, and plants (9,10). Although the N protein essential for the propagation of the virus adopts a highly conserved structure within a genus, N proteins from different genera differ in their primary sequences and 3D architecture markedly.…”