Group Group I (dsDNA) Subfamily Gammaherpesvirinae Scientific name Murid herpesvirus 68 Rank Subspecies | Family Herpesviridae Genus Rhadinovirus Higher classification Murid herpesvirus 4 Order Herpesvirales | |
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Similar Lymphocryptovirus, Human herpesvirus 5, Murinae, Myxoma virus, Alphaherpesvirinae | ||
Murid herpesvirus 68 (MHV-68) aka murine herpesvirus 68 is an isolate of Murid herpesvirus 4 which is a virus in the genus Rhadinovirus. It is a member of the subfamily Gammaherpesvirinae in the family of Herpesviridae. MHV-68 serves as a model for study of human gammaherpesviruses which cause significant human disease including B-cell lymphoma and Kaposi's sarcoma. The WUMS strain of MHV-68 was fully sequenced and annotated in 1997, and the necessity of most of its genes in viral replication was characterized by random transposon mutagenesis study .
MHV-68 surface proteins
Alpha-, beta-, and gammaherpesviruses display a heterodimer composed of glycoprotein H (gH) and glycoprotein L (gL) on their envelopes. This receptor is involved in the cell-to-cell transmission of the virus. Glycoprotein H has two conformations. Glycoprotein L is a chaperone protein which assures that gH takes on the correct conformation. When herpesviruses lack gL, gH misfolds. When alpha- or betaherpesviruses lack gL, they are noninfectious. When Murine Gammaherpesvirus 68 lacks gL, it remains infectious but is less able to bind to fibroblasts and epithelial cells.
The open reading frame M7 of the MHV-68 genome encodes for the surface receptor glycoprotein 150 (gp150). It is homologous to the Epstein-Barr virus membrane antigen gp350/220. MHV-68 is more closely related to the Kaposi's Sarcoma-associated herpesvirus (KSHV) than it is to the Epstein-Barr virus. Glycoprotein K8.1 is the KSHV homolog of MHV-68 gp150. MHV-68 is a very close relative of MHV-72. The MHV-68 M7 gene differs from the corresponding MHV-72 gene by five point mutations which alter four codons. Glycoprotein 150 allows MHV-68 to bind to B-cells.