Genetic and molecular biological analysis of protein-protein interactions in coronavirus assembly.

New York State Department of Health, Albany, New York, USA.
Advances in experimental medicine and biology (Impact Factor: 1.83). 02/2006; 581:163-73. DOI: 10.1007/978-0-387-33012-9_29
Source: PubMed

ABSTRACT Virions of coronaviruses (CoVs) are pleiomorphic, with a roughly spherical structure brought about by cooperation among a relatively small set of structural proteins and a membranous envelope acquired from the endoplasmic reticulum–Golgi intermediate compartment (ERGIC) (Fig. 1). Three integral membrane proteins reside in the envelope. The most salient of these is the spike glycoprotein (S), which mediates receptor attachment and fusion of the viral and host cell membranes. The membrane protein (M) is the most abundant virion component and gives the envelope its shape. The third constituent is the envelope protein (E), which, although minor in both size and quantity, plays a decisive role is envelope formation. In some group 2 CoVs, an additional protein, the hemagglutinin-esterase (HE), appears in the viral envelope. Finally, interior to the envelope, monomers of the nucleocapsid protein (N) wrap the genome into a helical structure.

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Sep 12, 2014