The porcine lymphotropic herpesvirus 1 encodes functional regulators of gene expression.
The porcine lymphotropic herpesviruses (PLHV) are discussed as possible risk factors in xenotransplantation because of the high prevalence of PLHV-1, PLHV-2 and PLHV-3 in pig populations world-wide and the fact that PLHV-1 has been found to be associated with porcine post-transplant lymphoproliferative disease. To provide structural and functional knowledge on the PLHV immediate-early (IE) transactivator genes, the central regions of the PLHV genomes were characterized by genome walking, sequence and splicing analysis. Three spliced genes were identified (ORF50, ORFA6/BZLF1(h), ORF57) encoding putative IE transactivators, homologous to (i) ORF50 and BRLF1/Rta, (ii) K8/K-bZIP and BZLF1/Zta and (iii) ORF57 and BMLF1 of HHV-8 and EBV, respectively. Expressed as myc-tag or HA-tag fusion proteins, they were located to the cellular nucleus. In reporter gene assays, several PLHV-promoters were mainly activated by PLHV-1 ORF50, to a lower level by PLHV-1 ORFA6/BZLF1(h) and not by PLHV-1 ORF57. However, the ORF57-encoded protein acted synergistically on ORF50-mediated activation.
Lindner
I
I
Robert Koch-Institut, P14 Molekulare Genetik und Epidemiologie von Herpesviren, Nordufer 20, 13353 Berlin, Germany.
Ehlers
B
B
Noack
S
S
Dural
G
G
Yasmum
N
N
Bauer
C
C
Goltz
M
M
D000818:Animals; D002460:Cell Line; D018142:Gammaherpesvirinae / Q000145:classification / Q000235:genetics* / Q000502:physiology*; D015967:Gene Expression Regulation, Viral / Q000502:physiology*; D005809:Genes, Regulator / Q000502:physiology*; D016679:Genome, Viral; D006801:Humans; D016366:Open Reading Frames; D013552:Swine / Q000821:virology; D013553:Swine Diseases / Q000821:virology; D014158:Transcription, Genetic; D014183:Transplantation, Heterologous / Q000009:adverse effects