Conserved cytoplasmic domain sequences mediate the ER export of VZV, HSV-1, and HCMV gB.
Glycoprotein B (gB) is conserved among the herpesviruses and participates in both virus entry and cell-cell spread. The ER export of VZV gB is mediated by two cytoplasmic domain regions, aa 818-826, which contains a YXXphi motif, and the C-terminal 17 aa. The current study examines whether related sequences in the cytoplasmic domains of HSV-1 and HCMV gB similarly influence the ER export of their gB homologs. Directed mutations were introduced into the cytoplasmic domains of HSV-1 and HCMV gB, and the efficiencies with which the mutated proteins acquired Golgi-dependent modifications were determined. Sequences homologous to VZV gB aa 818-826 were required for normal ER export of both HSV-1 gB and HCMV gB. However, the C-terminal regions of HSV-1 and HCMV gB had no impact on ER export. Therefore, alpha- and betaherpesvirus gB homologs share conserved ER export signals, but species-specific differences in the ER export of gB also exist.
Heineman
Thomas C
TC
Division of Infectious Diseases and Immunology, Saint Louis University School of Medicine, Saint Louis, MO 63110-0250, USA. heinemtc@slu.edu
Connolly
Patrick
P
Hall
Susan L
SL
Assefa
Daniel
D
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003587:Cytomegalovirus / Q000378:metabolism; D003593:Cytoplasm / Q000821:virology; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism; D006564:Herpesviridae / Q000378:metabolism*; D006566:Herpesviridae Infections / Q000821:virology*; D018259:Herpesvirus 1, Human / Q000378:metabolism; D014645:Herpesvirus 3, Human / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D016415:Sequence Alignment; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism*
D006023:Glycoproteins; D014759:Viral Envelope Proteins; C040495:glycoprotein B, Simplexvirus; C090198:glycoprotein B, varicella-zoster virus