Cytomegalovirus - Wikipedia

Genus of viruses

Cytomegalovirus
Typical "owl eye" intranuclear inclusion indicating CMV infection of a lung pneumocyte[1]
Virus classification
(unranked):	Virus
Realm:	Duplodnaviria
Kingdom:	Heunggongvirae
Phylum:	Peploviricota
Class:	Herviviricetes
Order:	Herpesvirales
Family:	Orthoherpesviridae
Subfamily:	Betaherpesvirinae
Genus:	Cytomegalovirus
Species
See text
Synonyms[2]
Human cytomegalovirus group

Cytomegalovirus (CMV) (from cyto- 'cell' via Greek κύτος kútos- 'container' + μέγας mégas 'big, megalo-' + -virus via Latin vīrus 'poison') is a genus of viruses in the order Herpesvirales, in the family Herpesviridae,[3] in the subfamily Betaherpesvirinae. Humans and other primates serve as natural hosts. The 11 species in this genus include human betaherpesvirus 5 (HCMV, human cytomegalovirus, HHV-5), which is the species that infects humans. Diseases associated with HHV-5 include mononucleosis and pneumonia,[4][5] and congenital CMV in infants can lead to variety of birth defects, including those involving the eyes, ears, liver, and spleen.[6]

In the medical literature, most mentions of CMV without further specification refer implicitly to human CMV. Human CMV is the most studied of all cytomegaloviruses.[7]

MX2/MXB protein was identified as a restriction factor for herpesviruses, which acts at a very early stage of the replication cycle and MX2/MXB restriction of herpesvirus requires GTPase activity.[8]

Taxonomy

[edit]

Within the Herpesviridae, CMV belongs to the Betaherpesvirinae subfamily, which also includes the genera Muromegalovirus and Roseolovirus (human herpesvirus 6 and human herpesvirus 7).[9] It is also related to other herpesviruses within the Alphaherpesvirinae subfamily, which includes herpes simplex viruses 1 and 2 and varicella-zoster virus, and the Gammaherpesvirinae subfamily, which includes Epstein–Barr virus and Kaposi's sarcoma-associated herpesvirus.[7]

Several species of Cytomegalovirus have been identified and classified for different mammals.[9] The most studied is Human cytomegalovirus (HCMV), which is also known as Human betaherpesvirus 5 (HHV-5). Other primate CMV species include Chimpanzee cytomegalovirus (CCMV) that infects chimpanzees and orangutans, and Simian cytomegalovirus (SCCMV) and Rhesus cytomegalovirus (RhCMV) that infect macaques; CCMV is known as both Panine beta herpesvirus 2 (PaHV-2) and Pongine betaherpesvirus 4 (PoHV-4).[10] SCCMV is called cercopithecine betaherpesvirus 5 (CeHV-5)[11] and RhCMV, Cercopithecine betaherpesvirus 8 (CeHV-8).[12] A further two viruses found in the night monkey are tentatively placed in the genus Cytomegalovirus, and are called Herpesvirus aotus 1 and Herpesvirus aotus 3. Rodents also have viruses previously called cytomegaloviruses that are now reclassified under the genus Muromegalovirus; this genus contains Mouse cytomegalovirus (MCMV) is also known as Murid betaherpesvirus 1 (MuHV-1) and the closely related Murid betaherpesvirus 2 (MuHV-2) that is found in rats.[13]

Species

[edit]

The following 11 species are assigned to the genus in ICTV 2022:[5]

• Cytomegalovirus aotinebeta1
• Cytomegalovirus cebinebeta1
• Cytomegalovirus cercopithecinebeta5
• Cytomegalovirus humanbeta5
• Cytomegalovirus macacinebeta3
• Cytomegalovirus macacinebeta8
• Cytomegalovirus mandrillinebeta1
• Cytomegalovirus paninebeta2
• Cytomegalovirus papiinebeta3
• Cytomegalovirus papiinebeta4
• Cytomegalovirus saimiriinebeta4

Structure

[edit]

Viruses in Cytomegalovirus are enveloped, with icosahedral, spherical to pleomorphic, and round geometries, and T=16 symmetry. The diameter is around 150–200 nm. Genomes are linear and nonsegmented, around 200 kb in length.[4]

Genus	Structure	Symmetry	Capsid	Genomic arrangement	Genomic segmentation
Cytomegalovirus	Spherical pleomorphic	T=16	Enveloped	Linear	Monopartite

Genome

[edit]

Herpesviruses have some of the largest genomes among human viruses, often encoding hundreds of proteins. For instance, the double‑stranded DNA (dsDNA) genome of wild-type HCMV strains has a size of around 235 kb and encodes at least 208 proteins. It is thus longer than all other human herpesviruses and one of the longest genomes of all human viruses in general. It has the characteristic herpesvirus class E genome architecture, consisting of two unique regions (unique long UL and unique short US), both flanked by a pair of inverted repeats (terminal/internal repeat long TRL/IRL and internal/terminal repeat short IRS/TRS). Both sets of repeats share a region of a few hundred bps, the so-called "a sequence"; the other regions of the repeats are sometimes referred to as "b sequence" and "c sequence".[14]

Life cycle

[edit]

Viral replication is nuclear and lysogenic. Entry into the host cell is achieved by attachment of the viral glycoproteins to host receptors, which mediates endocytosis. Replication follows the dsDNA bidirectional replication model. DNA templated transcription, with some alternative splicing mechanism is the method of transcription. Translation takes place by leaky scanning. The virus exits the host cell by nuclear egress and budding. Humans and monkeys serve as the natural hosts. Transmission routes are dependent on coming into contact with bodily fluids (such as saliva, urine, and genital secretions) from an infected individual.[4][15]

Genus	Host details	Tissue tropism	Entry details	Release details	Replication site	Assembly site	Transmission
Cytomegalovirus	humans; monkeys	Epithelial mucosa	Glycoproteins	Budding	Nucleus	Nucleus	Urine; saliva; congenital

All herpesviruses share a characteristic ability to remain latent within the body over long periods. Although they may be found throughout the body, CMV infections are frequently associated with the salivary glands in humans and other mammals.[9]

Genetic engineering

[edit]

The CMV promoter is commonly included in vectors used in genetic engineering work conducted in mammalian cells, as it is a strong promoter and drives constitutive expression of genes under its control.[16]

History

[edit]

Cytomegalovirus was first observed by German pathologist Hugo Ribbert in 1881 when he noticed enlarged cells with enlarged nuclei present in the cells of an infant.[17] Years later, between 1956 and 1957, Thomas Huckle Weller together with Smith and Rowe independently isolated the virus, known thereafter as "cytomegalovirus".[18] In 1990, the first draft of human cytomegalovirus genome was published,[19] the biggest contiguous genome sequenced at that time.[20]

See also

[edit]

• CMV polyradiculomyelopathy
• Human cytomegalovirus

References

[edit]

1. ^ Mattes FM, McLaughlin JE, Emery VC, Clark DA, Griffiths PD (August 2000). "Histopathological detection of owl's eye inclusions is still specific for cytomegalovirus in the era of human herpesviruses 6 and 7". Journal of Clinical Pathology. 53 (8): 612–614. doi:10.1136/jcp.53.8.612. PMC 1762915. PMID 11002765.
2. ^ Francki RI, Fauquet CM, Knudson DL, Brown (1991). "Classification and nomenclature of viruses. Fifth Report of the International Committee on Taxonomy of Viruses" (PDF). Arch. Virol.: 107.
3. ^ Anshu A, Tan D, Chee SP, Mehta JS, Htoon HM (August 2017). "Interventions for the management of CMV-associated anterior segment inflammation". The Cochrane Database of Systematic Reviews. 2017 (8) CD011908. doi:10.1002/14651858.cd011908.pub2. PMC 6483705. PMID 28838031.
4. ^ a b c "Viral Zone". ExPASy. Retrieved 15 June 2015.
5. ^ a b "Virus Taxonomy: 2022 Release". International Committee on Taxonomy of Viruses (ICTV). March 2023. Retrieved 16 September 2022.
6. ^ "Cytomegalovirus (CMV)". nhs.uk. 23 October 2017. Retrieved 30 October 2025.
7. ^ a b Ryan KJ, Ray CG, eds. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. pp. 556, 566–569. ISBN 978-0-8385-8529-0.
8. ^ Staeheli P, Haller O (December 2018). "Human MX2/MxB: a Potent Interferon-Induced Postentry Inhibitor of Herpesviruses and HIV-1". Journal of Virology. 92 (24). doi:10.1128/JVI.00709-18. PMC 6258936. PMID 30258007.
9. ^ a b c Koichi Y, Arvin AM, Campadelli-Fiume G, Mocarski E, Patrick M, Roizman B, Whitley R (2007). Human Herpesviruses: Biology, Therapy, and Immunoprophylaxis. Cambridge, UK: Cambridge University Press. ISBN 978-0-521-82714-0.
10. ^ "Panine betaherpesvirus 2 (Chimpanzee cytomegalovirus)". www.uniprot.org. Retrieved 13 March 2019.
11. ^ "Simian cytomegalovirus (strain Colburn)". www.uniprot.org. Retrieved 13 March 2019.
12. ^ "Macacine betaherpesvirus 3 (Rhesus cytomegalovirus)". www.uniprot.org. Retrieved 13 March 2019.
13. ^ "Murid herpesvirus 1, complete genome". 13 August 2018. Retrieved 13 March 2019 – via NCBI Nucleotide.
14. ^ a b Sijmons S, Van Ranst M, Maes P (March 2014). "Genomic and functional characteristics of human cytomegalovirus revealed by next-generation sequencing". Viruses. 6 (3): 1049–1072. doi:10.3390/v6031049. PMC 3970138. PMID 24603756.
15. ^ Cannon MJ, Hyde TB, Schmid DS (July 2011). "Review of cytomegalovirus shedding in bodily fluids and relevance to congenital cytomegalovirus infection". Reviews in Medical Virology. 21 (4): 240–255. doi:10.1002/rmv.695. PMC 4494736. PMID 21674676.
16. ^ Morgan K (3 April 2014). "Plasmids 101: The Promoter Region – Let's Go!". Addgene Blog.
17. ^ Reddehase MJ, Lemmermann N, eds. (2006). "Preface". Cytomegaloviruses: Molecular Biology and Immunology. Horizon Scientific Press. p. xxiv. ISBN 9781904455028.
18. ^ Craig JM, Macauley JC, Weller TH, Wirth P (January 1957). "Isolation of intranuclear inclusion producing agents from infants with illnesses resembling cytomegalic inclusion disease". Proceedings of the Society for Experimental Biology and Medicine. 94 (1): 4–12. doi:10.3181/00379727-94-22841. PMID 13400856. S2CID 29263626.
19. ^ Chee MS, Bankier AT, Beck S, Bohni R, Brown CM, Cerny R, et al. (1990). "Analysis of the Protein-Coding Content of the Sequence of Human Cytomegalovirus Strain AD169". Cytomegaloviruses. Current Topics in Microbiology and Immunology. Vol. 154. Springer Berlin Heidelberg. pp. 125–169. doi:10.1007/978-3-642-74980-3_6. ISBN 978-3-642-74982-7. PMID 2161319.
20. ^ Martí-Carreras J, Maes P (April 2019). "Human cytomegalovirus genomics and transcriptomics through the lens of next-generation sequencing: revision and future challenges". Virus Genes. 55 (2): 138–164. doi:10.1007/s11262-018-1627-3. PMC 6458973. PMID 30604286.

External links

[edit] Wikimedia Commons has media related to Cytomegalovirus. Wikispecies has information related to Cytomegalovirus.

• ICTV

Classification	D ICD-10: B25 ICD-9-CM: 078.5 MeSH: D003586
External resources	MedlinePlus: 000568

v t e Taxonomy of the Herpesvirales
Higher taxonomy: Duplodnaviria > Heunggongvirae > Peploviricota > Herviviricetes > Herpesvirales
Malacoherpesviridae	Aurivirus AbHV-1 Ostreavirus OsHV-1
Alloherpesviridae	Batrachovirus RaHV-1 2 3 Cyprinivirus AngHV-1 CyHV-1 2 3 Ictalurivirus AciHV-2 IcHV-1 2 Salmonivirus SalHV-1 2 3
HerpesviridaeIgHV-2	αChHV-6 Iltovirus GaHV-1 PsHV-1 Mardivirus AnHV-1 CoHV-1 GaHV-2 3 MeHV-1 SpAHV-1 Scutavirus ChHV-5 TeHV-3 Simplexvirus AtHV-1 BoHV-2 CeHV-2 HHV-1 2 LeHV-4 McHV-1 2 3 MaHV-1 2 PnHV-3 PaHV-2 PtHV-1 SaHV-1 Varicellovirus BoHV-1 5 BuHV-1 CaHV-1 CpHV-1 CeHV-9 CvHV-1 2 3 EHV-1 3 4 8 9 FeHV-1 HHV-3 MoHV-1 PhHV-1 SuHV-1 β Cytomegalovirus AoHV-1 CbHV-1 CeHV-5 HHV-5 McHV-3 8 MnHV-1 PnHV-2 PaHV-3 4 SaHV-4 Muromegalovirus MuHV-1 2 8 Proboscivirus ElHV-1 4 5 Quwivirus CaHV-2 MschBHV1 TuHV-1 Roseolovirus HHV-6A 6B 7 McHV-9 MuHV-3 SuHV-2 γEHV-7PhHV-2SgHV-1 Bossavirus DeHV-1 Lymphocryptovirus CalHV-3 CeHV-14 GoHV-1 HHV-4 McHV-4 10 PnHV-1 PaHV-1 PoHV-2 Macavirus AlHV-1 2 BoHV-6 CpHV-2 HiHV-1 OvHV-2 SuHV-3 4 5 Manticavirus PhaHV-1 VoHV-1 Percavirus EHV-2 5 FeHV-1 MusHV-1 PhHV-3 VeHV-1 Patagivirus VeHV-3 Rhadinovirus AtHV-2 3 BoHV-4 CrHV-2 HHV-8 McHV-5 8 11 12 MuHV-4 7 SaHV-2
Unassigned species listed below parent taxon –– Source: ICTV –– Wikispecies

v t e Baltimore (virus classification)
DNA	I: dsDNA viruses Adnaviria Zilligvirae Taleaviricota Tokiviricetes Ligamenvirales Lipothrixviridae Rudiviridae Primavirales Tristromaviridae Duplodnaviria Heunggongvirae Peploviricota Herviviricetes Herpesvirales Alloherpesviridae Herpesviridae Malacoherpesviridae Uroviricota Caudoviricetes Caudovirales Ackermannviridae Autographiviridae Chaseviridae Demerecviridae Drexlerviridae Guelinviridae Herelleviridae Myoviridae Podoviridae Rountreeviridae Salasmaviridae Schitoviridae Siphoviridae Zobellviridae Monodnaviria Shotokuvirae Cossaviricota Papovaviricetes Sepolyvirales Polyomaviridae Zurhausenvirales Papillomaviridae Varidnaviria Bamfordvirae Nucleocytoviricota Pokkesviricetes Asfuvirales Asfarviridae Chitovirales Poxviridae Megaviricetes Algavirales Phycodnaviridae Imitervirales Mimiviridae Pimascovirales Ascoviridae Iridoviridae Marseilleviridae Preplasmiviricota Maveriviricetes Priklausovirales Lavidaviridae Polintoviricetes Orthopolintovirales Adintoviridae Tectiliviricetes Belfryvirales Turriviridae Kalamavirales Tectiviridae Rowavirales Adenoviridae Vinavirales Corticoviridae Helvetiavirae Dividoviricota Laserviricetes Halopanivirales Matshushitaviridae Simuloviridae Sphaerolipoviridae Unassigned Naldaviricetes Lefavirales Baculoviridae Hytrosaviridae Nudiviridae Unassigned Nimaviridae Unassigned Families: Ampullaviridae Bicaudaviridae Clavaviridae Fuselloviridae Globuloviridae Guttaviridae Halspiviridae Ovaliviridae Plasmaviridae Polydnaviridae Portogloboviridae Thaspiviridae Genera: Dinodnavirus Rhizidiovirus II: ssDNA viruses Monodnaviria Loebvirae Hofneiviricota Faserviricetes Tubulavirales Inoviridae Paulinoviridae Plectroviridae Sangervirae Phixviricota Malgrandaviricetes Petitvirales Microviridae Shotokuvirae Commensaviricota Cardeaviricetes Sanitavirales Anelloviridae Cossaviricota Mouviricetes Polivirales Bidnaviridae Quintoviricetes Piccovirales Parvoviridae Cressdnaviricota Arfiviricetes Baphyvirales Bacilladnaviridae Cirlivirales Circoviridae Cremevirales Smacoviridae Mulpavirales Metaxyviridae Nanoviridae Recrevirales Redondoviridae Repensiviricetes Geplafuvirales Geminiviridae Genomoviridae Trapavirae Saleviricota Huolimaviricetes Haloruvirales Pleolipoviridae Varidnaviria Abedenavirae Produgelaviricota Ainoaviricetes Lautamovirales Finnlakeviridae Unassigned Families: Spiraviridae
RNA	III: dsRNA viruses Riboviria Orthornavirae Duplornaviricota Chrymotiviricetes Ghabrivirales Chrysoviridae Megabirnaviridae Quadriviridae Totiviridae Resentoviricetes Reovirales Reoviridae Vidaverviricetes Mindivirales Cystoviridae Pisuviricota Duplopiviricetes Durnavirales Amalgaviridae Curvulaviridae Hypoviridae Picobirnaviridae Partitiviridae Unassigned Families: Birnaviridae Polymycoviridae Genera: Botybirnavirus IV: (+)ssRNA viruses Riboviria Orthornavirae Kitrinoviricota Alsuviricetes Hepelivirales Alphatetraviridae Benyviridae Hepeviridae Matonaviridae Martellivirales Bromoviridae Closteroviridae Endornaviridae Kitaviridae Mayoviridae Togaviridae Virgaviridae Tymovirales Alphaflexiviridae Betaflexiviridae Deltaflexiviridae Gammaflexiviridae Tymoviridae Flasuviricetes Amarillovirales Flaviviridae Magsaviricetes Nodamuvirales Nodaviridae Sinhaliviridae Tolucaviricetes Tolivirales Carmotetraviridae Luteoviridae Tombusviridae Lenarviricota Leviviricetes Norzivirales Atkinsviridae Duinviridae Fiersviridae Solspiviridae Timlovirales Blumeviridae Steitzviridae Amabiliviricetes Wolframvirales Narnaviridae Howeltoviricetes Cryppavirales Mitoviridae Miaviricetes Ourlivirales Botourmiaviridae Pisuviricota Pisoniviricetes Nidovirales Abyssoviridae Arteriviridae Cremegaviridae Coronaviridae Euroniviridae Gresnaviridae Medioniviridae Mesoniviridae Mononiviridae Nanghoshaviridae Nanhypoviridae Olifoviridae Roniviridae Tobaniviridae Picornavirales Picornaviridae Marnaviridae Solinviviridae Caliciviridae Iflaviridae Secoviridae Dicistroviridae Polycipiviridae Sobelivirales Alvernaviridae Barnaviridae Solemoviridae Stelpaviricetes Patatavirales Potyviridae Stellavirales Astroviridae Unassigned Families: Permutotetraviridae Sarthroviridae V: (–)ssRNA viruses Riboviria Orthornavirae Negarnaviricota Chunqiuviricetes Muvirales Qinviridae Ellioviricetes Bunyavirales Cruliviridae Arenaviridae Fimoviridae Hantaviridae Leishbuviridae Mypoviridae Nairoviridae Peribunyaviridae Phasmaviridae Phenuiviridae Tospoviridae Wupedeviridae Insthoviricetes Articulavirales Amnoonviridae Orthomyxoviridae Milneviricetes Serpentovirales Aspiviridae Monjiviricetes Jingchuvirales Aliusviridae Chuviridae Crepuscuviridae Myriaviridae Natareviridae Mononegavirales Artoviridae Bornaviridae Filoviridae Lispiviridae Mymonaviridae Nyamiviridae Paramyxoviridae Pneumoviridae Rhabdoviridae Sunviridae Xinmoviridae Yunchangviricetes Goujianvirales Yueviridae Ambiviricota Suforviricetes Crytulvirales Dumbiviridae Quambiviridae Trimbiviridae Unambiviridae
RT	VI: ssRNA-RT viruses Riboviria Pararnavirae Artverviricota Revtraviricetes Ortervirales Belpaoviridae Metaviridae Pseudoviridae Retroviridae VII: dsDNA-RT viruses Riboviria Pararnavirae Artverviricota Revtraviricetes Blubervirales Hepadnaviridae Ortervirales Caulimoviridae

v t e Infectious diseases – viral systemic diseases
Oncovirus	DNA virus HBV Hepatocellular carcinoma HPV Cervical cancer Anal cancer Penile cancer Vulvar cancer Vaginal cancer Oropharyngeal cancer KSHV Kaposi's sarcoma EBV Nasopharyngeal carcinoma Burkitt's lymphoma Hodgkin lymphoma Follicular dendritic cell sarcoma Extranodal NK/T-cell lymphoma, nasal type MCPyV Merkel-cell carcinoma RNA virus HCV Hepatocellular carcinoma Splenic marginal zone lymphoma HTLV-I Adult T-cell leukemia/lymphoma
Immune disorders	HIV AIDS
Central nervous system	Encephalitis/meningitis DNA virus Human polyomavirus 2 Progressive multifocal leukoencephalopathy RNA virus MeV Subacute sclerosing panencephalitis LCV Lymphocytic choriomeningitis Arbovirus encephalitis Orthomyxoviridae (probable) Encephalitis lethargica RV Rabies Chandipura vesiculovirus Herpesviral meningitis Ramsay Hunt syndrome type 2 Myelitis Poliovirus Poliomyelitis Post-polio syndrome HTLV-I Tropical spastic paraparesis Eye Cytomegalovirus Cytomegalovirus retinitis HSV Herpes of the eye
Cardiovascular	CBV Pericarditis Myocarditis
Respiratory system/acute viralnasopharyngitis/viral pneumonia	DNA virus Epstein–Barr virus EBV infection/Infectious mononucleosis Cytomegalovirus RNA virus IV: Coronavirus 229E/NL63/HKU1/OC43 Common cold MERS coronavirus Middle East respiratory syndrome SARS coronavirus Severe acute respiratory syndrome SARS-CoV-2 COVID-19 V, Orthomyxoviridae: Influenza virus A/B/C/D Influenza/Avian influenza V, Paramyxoviridae: Human parainfluenza viruses Parainfluenza Human orthopneumovirus hMPV
Human digestive system	Pharynx/Esophagus MuV Mumps Cytomegalovirus Cytomegalovirus esophagitis Gastroenteritis/diarrhea DNA virus Adenovirus Adenovirus infection RNA virus Rotavirus (Gastroenteritis) Norovirus Astrovirus Coronavirus Hepatitis DNA virus HBV (B) RNA virus CBV HAV (A) HCV (C) HDV (D) HEV (E) Pancreatitis CBV
Urogenital	BK virus MuV Mumps

v t e Vertically transmitted infections
Gestational	Viruses Congenital rubella syndrome Congenital cytomegalovirus infection Neonatal herpes simplex Hepatitis B Congenital varicella syndrome HIV Fifth disease Bacteria Congenital syphilis Other Toxoplasmosis transplacental TORCH complex
During birth	transcervical Candidiasis Gonorrhea Listeriosis
Late pregnancy	Listeriosis Congenital cytomegalovirus infection
By breastfeeding	Breastfeeding Tuberculosis HIV

Taxon identifiers
Cytomegalovirus	Wikidata: Q6946 Wikispecies: Cytomegalovirus CoL: 3Z6L EoL: 67669 GBIF: 10144710 IRMNG: 1096505 NCBI: 10358 WoRMS: 600117

Authority control databases: National	Czech Republic