Embecovirus

{{Short description|Subgenus of viruses}} {{Virusbox | image = 109239.fig.001abcd.png | image_alt = | image_caption = Murine coronavirus (MHV) virion electron micrograph, schematic structure, and genome. | taxon = Embecovirus | synonyms = | synonyms_ref = | subdivision_ranks = | subdivision_ref = | subdivision = }}

'''''Embecovirus''''' is a subgenus of coronaviruses in the genus ''Betacoronavirus''.<ref name=ICTV>{{cite web |title=Virus Taxonomy: 2018 Release |url=https://ictv.global/taxonomy |website=International Committee on Taxonomy of Viruses (ICTV) |access-date=24 January 2019 |language=en |date=October 2018 |archive-url=https://web.archive.org/web/20180304035352/https://talk.ictvonline.org/taxonomy/ |archive-date=4 March 2018 |url-status=live }}</ref> The viruses in this subgenus, unlike other coronaviruses, have a hemagglutinin esterase (HE) gene.<ref name=":0" /> The viruses in the subgenus were previously known as '''group 2a coronaviruses'''.<ref>{{Cite journal|last1=Woo|first1=Patrick C. Y.|last2=Wang|first2=Ming|last3=Lau|first3=Susanna K. P.|last4=Xu|first4=Huifang|last5=Poon|first5=Rosana W. S.|last6=Guo|first6=Rongtong|last7=Wong|first7=Beatrice H. L.|last8=Gao|first8=Kai|last9=Tsoi|first9=Hoi-wah|last10=Huang|first10=Yi|last11=Li|first11=Kenneth S. M.|date=February 2007|title=Comparative Analysis of Twelve Genomes of Three Novel Group 2c and Group 2d Coronaviruses Reveals Unique Group and Subgroup Features|journal=Journal of Virology|volume=81|issue=4|pages=1574–1585|doi=10.1128/JVI.02182-06|issn=0022-538X|pmc=1797546|pmid=17121802|quote=See figure 2.}}</ref><ref>{{Cite journal|last1=Wong|first1=Antonio C. P.|last2=Li|first2=Xin|last3=Lau|first3=Susanna K. P.|last4=Woo|first4=Patrick C. Y.|date=2019-02-20|title=Global Epidemiology of Bat Coronaviruses|journal=Viruses|volume=11|issue=2|pages=174|doi=10.3390/v11020174|issn=1999-4915|pmc=6409556|pmid=30791586|quote=CoVs are classified into four genera, Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus. Within Betacoronavirus, they can be further subclassified into lineages A, B, C and D [1]. In 2018, these four lineages were reclassified as subgenera of Betacoronavirus, and renamed as Embecovirus (previous lineage A), Sarbecovirus (previous lineage B), Merbecovirus (previous lineage C) and Nobecovirus (previous lineage D) [2]. In addition, a fifth subgenus, Hibecovirus, was also included (Figure 1) [2].|doi-access=free}}</ref>

== Taxonomy == The subgenus contains the following species, listed by scientific name and followed by the exemplar virus of the species:<ref>{{cite web|title=Virus Taxonomy: 2024 Release|url=https://ictv.global/taxonomy|publisher=International Committee on Taxonomy of Viruses|access-date=9 April 2025}}</ref><ref>{{cite web |title=Species List: ''Coronaviridae'' |url=https://ictv.global/report/chapter/coronaviridae/taxonomy/coronaviridae |publisher=International Committee on Taxonomy of Viruses |access-date=9 April 2025}}</ref>

* ''Betacoronavirus gravedinis'', Human coronavirus OC43 * ''Betacoronavirus hongkongense'', Human coronavirus HKU1 * ''Betacoronavirus muris'', Murine hepatitis virus * ''Betacoronavirus myodae'', Myodes rufocanus vole coronavirus 2/JL2014 * ''Betacoronavirus ratti'', Betacoronavirus HKU24

== Structure ==

The viruses of this subgenus, like other coronaviruses, have a lipid bilayer envelope in which the membrane (M), envelope (E) and spike (S) structural proteins are anchored.<ref name=":1">{{Citation|last1=Lai|first1=Michael M. C.|title=The Molecular Biology of Coronaviruses; III. Structure of Virions; A. Virion Morphology|date=1997-01-01|journal=Advances in Virus Research|volume=48|pages=5–6|editor-last=Maramorosch|editor-first=Karl|publisher=Academic Press|language=en|last2=Cavanagh|first2=David|doi=10.1016/S0065-3527(08)60286-9|pmid=9233431|pmc=7130985|editor2-last=Murphy|editor2-first=Frederick A.|editor3-last=Shatkin|editor3-first=Aaron J.}}</ref> Unlike other coronaviruses, viruses in this subgenus also have an additional shorter spike-like structural protein called hemagglutinin esterase (HE).<ref name=":0">{{Cite journal|last1=Woo|first1=Patrick C. Y.|last2=Huang|first2=Yi|last3=Lau|first3=Susanna K. P.|last4=Yuen|first4=Kwok-Yung|date=2010-08-24|title=Coronavirus Genomics and Bioinformatics Analysis|journal=Viruses|volume=2|issue=8|pages=1804–1820|doi=10.3390/v2081803|issn=1999-4915|pmc=3185738|pmid=21994708|quote=In all members of Betacoronavirus subgroup A, a haemagglutinin esterase (HE) gene, which encodes a glycoprotein with neuraminate O-acetyl-esterase activity and the active site FGDS, is present downstream to ORF1ab and upstream to S gene (Figure 1).|doi-access=free}}</ref><ref name=":02">{{Cite journal|last1=Woo|first1=Patrick C. Y.|last2=Huang|first2=Yi|last3=Lau|first3=Susanna K. P.|last4=Yuen|first4=Kwok-Yung|date=2010-08-24|title=Coronavirus Genomics and Bioinformatics Analysis|journal=Viruses|volume=2|issue=8|pages=1804–1820|doi=10.3390/v2081803|issn=1999-4915|pmc=3185738|pmid=21994708|quote=The presence of HE genes exclusively in members of Betacoronavirus subgroup A, but not members of Betacoronavirus subgroup B, C and D suggested that the recombination had probably occurred in the ancestor of members of Betacoronavirus subgroup A, after diverging from the ancestor of other subgroups of Betacoronavirus.|doi-access=free}}</ref>

==Recombination==

Genetic recombination can occur when two or more viral genomes are present in the same host cell. The dromedary camel beta-coronavirus (Beta-CoV HKU23) exhibits genetic diversity in the African camel population.<ref name = So2019>Diversity of Dromedary Camel Coronavirus HKU23 in African Camels Revealed Multiple Recombination Events among Closely Related Betacoronaviruses of the Subgenus Embecovirus. So RTY, et al. J Virol. 2019. PMID 31534035</ref> Contributing to this diversity are several recombination events that had taken place in the past between closely related Beta-CoVs of the subgenus Embecovirus.<ref name = So2019/>

== See also ==

*''Sarbecovirus'' (group 2b) *''Merbecovirus'' (group 2c) *''Nobecovirus'' (group 2d)

==References==

Category:Virus subgenera Category:Betacoronaviruses