Abstract
The Bunyavirales order accommodates related viruses (bunyaviruses) with segmented, linear, single-stranded, negative- or ambi-sense RNA genomes. Their glycoproteins form capsomeric projections or spikes on the virion surface and play a crucial role in virus entry, assembly, morphogenesis. Bunyavirus glycoproteins are encoded by a single RNA segment as a polyprotein precursor that is co- and post-translationally cleaved by host cell enzymes to yield two mature glycoproteins, Gn and Gc (or GP1 and GP2 in arenaviruses). These glycoproteins undergo extensive N-linked glycosylation and despite their cleavage, remain associated to the virion to form an integral transmembrane glycoprotein complex. This review summarizes recent advances in our understanding of the molecular biology of bunyavirus glycoproteins, including their processing, structure, and known interactions with host factors that facilitate cell entry.
Highlights
Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G61 1QH, UK
Our improving understanding of bunyavirus glycoproteins has enhanced our appreciation of the pathobiological diversity within this important group of pathogens
Much remains to be elucidated on the process of bunyavirus glycoprotein folding and biosynthesis, their diverse assemblies and host-interactions, and how they interact and recruit the N protein during virus assembly
Summary
The glycoproteins of all viruses in the order Bunyavirales are encoded as a GPC within a single open reading frame (ORF). For viruses belonging to the Peribunyaviridae, Nairoviridae and Phasmaviridae families, and for some phleboviruses (Phenuiviridae), the M segment encodes a nonstructural protein (NS), termed NSm, within the glycoprotein precursor. Of tenuiviruses (Phenuiviridae) follow an ambisense strategy to encode their GPCs and non-structural proteins [29,30] (Figure 2). Arenavirus S segments encode their GPC in the genomic sense and the N protein in the antigenomic sense, the two ORFs being separated by a non-coding, intergenic region containing a hairpin loop involved in transcription termination (reviewed by [31,32]). The genomic organization of the RNA segments encoding viral glycoprotein precursors of well-studied bunyaviruses can be grouped according to the coding strategies and the gene order of the proteins (Figure 2)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
