Identification and sequence analysis of the Marek's disease virus serotype 2 homologous genes of the herpes simplex virus type 1 UL25, UL26 and UL26.5 genes

Assembly of Marek's disease virus (MDV) capsids using recombinant baculoviruses expressing MDV capsid proteins

The genes UL18, UL19, UL26, UL26.5, UL35 and UL38 of Marek's disease virus 1 (MDV-1) strain RB1B, encoding the homologues of herpes simplex virus type 1 (HSV-1) capsid proteins VP23, VP5, VP21-VP24, preVP22a, VP26 and VP19C, were identified and sequenced. Recombinant baculoviruses were used to express the six capsid genes in insect cells. Coexpression of the six genes or of UL18, UL19, UL26.5 and UL38 in insect cells resulted in the formation of capsids with a large core. In addition, electron microscopy of thin sections clearly revealed the presence of large numbers of small spherical particles. Experimental coinfection demonstrated that these small particles were associated with production of the preVP22a protein.

Identification of the Marek's disease virus serotype 2 genes homologous to the glycoprotein B (UL27), ICP18.5 (UL28) and major DNA-binding protein (UL29) genes of herpes simplex virus type 1

We determined the nucleotide sequence of non-pathogenic Marek's disease virus serotype 2 (MDV2) strain HPRS24 glycoprotein B (gB) (UL27), ICP18.5 (UL28) and major DNA-binding protein (MDBP) (UL29) genes homologous to herpes simplex virus type 1 (HSV-1). The sequence data revealed that important motives in the proteins are conserved in MDV2 ICP18.5 and MDBP, however the sequence of viral DNA replication origin which exists in the regions between the UL29 and UL30 genes of other alphaherpesviruses was not found in the regions of the MDV2 genome. By northern blot analyses, we also demonstrated that 8.9, 5.0 and 2.6 kb transcripts were actually transcribed from the sequenced region in MDV2-infected cells. The MDV2 UL28 and UL29 genes have not been reported in other serotypes of MDV.