Morphology (Structure) & Function of Coronaviruses

SUMMERIZER & FIGURE: SEOK WOO YANG, MD & PhD

DATE: 2020.03.08

CONTENT:

GENOMIC TYPE	SS(single stranded) RNA virus
SIZE	Pleomorphic, ranging from 60 to 220 nm in diameter
ETYMOLOGY	(Latin) corona = crown.
APPEARANCE	A fringed appearance of widely spaced club-spaced surface projections, viral spike(S) peplomers, reminiscent of a solar corona.
PROTEINS that contribute to the overall structure of coronaviruses	Spike (S), envelope (E), transmembrane (M), and nucleocapsid (N)
OUTLINE of coronaviruses	Envelope composed of lipid bilayer.
GENOME	Non-segmented single-stranded positive-sense RNA of approximately 30 kb
PROPERTY	The ability to haemagglutinate
Spike (S) protein	1. Virions(infected form of the virus) can be bound to specific surface receptors in the plasma membrane of the host cell via the N-terminus of the S proteins [9] 2. The major inducer of neutralizing antibody
Envelope (E) protein	A small, integral membrane protein involved in several aspects of the virus’ life cycle, such as assembly, budding, envelope formation, and pathogenesis.[2]
Transmembrane (M) protein	1. The virion to fuse into the cell and to make protein antigenic.[3][4][5] 2. N protein forms a complex by binding to genomic RNA and M protein triggers the formation of interacting virions in this endoplasmic reticulum-Golgi apparatus intermediate compartment (ERGIC) with this complex.[6][7][8]
Nucleocapsid (N) protein	Virion structure, replication and transcription of coronaviruses.

Fig. Coronavirus Structure

REFERENCE

[1] David Greenwood, Richard C. B. Slack, John F. Peutherer. MEDICAL MICROBIOLOGY. 16 ed. 2002. Churchill Livingstone.

[2] Schoeman, D., Fielding, B.C. Coronavirus envelope protein: current knowledge. Virol J 16, 69 (2019).

[3] de Haan CA, de Wit M, Kuo L, Montalto-Morrison C, Haagmans BL, Weiss SR, et al. The glycosylation status of the murine hepatitis coronavirus M protein affects the interferogenic capacity of the virus in vitro and its ability to replicate in the liver but not the brain. Virology. 2003; 312: 395-406.

[4] Alexander S, Elder JH. Carbohydrate dramatically infl uences immune reactivity of antisera to viral glycoprotein antigens. Science. 1984; 226: 1328-1330.

[5] Wissink EH, Kroese MV, Maneschijn Bonsing JG, Meulenberg JJ, van Rijn PA, Rijsewijk FA, et al. Signifi cance of the oligosaccharides of the porcine reproductive and respiratory syndrome virus glycoproteins GP2a and GP5 for infectious virus production. J Gen Virol. 2004; 85: 3715-3723. 

[6] de Haan CA, Masters PS, Lili Kuo, Harry Vennema, Peter JM, Rottier. Coronavirus particle assembly: primary structure requirements of the membrane protein. J Virol. 1998; 72: 6838-6850. 

[7] Escors D, Ortego J, Enjuanes L. The membrane M protein of the transmissible gastroenteritis coronavirus binds to the internal core through the carboxy-terminus. Adv Exp Med Biol. 2001; 494: 589-593. 

[8] Narayanan K, Makino S. Characterization of nucleocapsid-M protein interaction in murine coronavirus. Adv Exp Med Biol. 2001; 494:577-582. 

[9] Lewicki DN, Gallagher TM. Quaternary structure of coronavirus spikes in complex with carcinoembryonic antigen- related cell adhesion molecule cellular receptors. J Biol Chem. 2002; 277: 19727-19734.