A cluster of latently expressed genes in Kaposi's sarcoma-associated herpesvirus

Dirk Dittmer, Michael Lagunoff, Rolf Renne, Katherine Staskus, Ashley Haase, Don Ganem

Research output: Contribution to journalArticlepeer-review

360 Scopus citations


Infection with Kaposi's sarcoma-associated herpesvirus (KSHV) is closely associated with Kaposi's sarcoma (KS) and primary effusion lymphoma, with vital genomes present in a latent state in the majority of tumor cells. Here we describe a cluster of latently expressed vital genes whose mRNAs are generated from a common promoter. Two mRNAs in this region encode the latency-associated nuclear antigen, the product of open reading frame 73 (ORF73). The larger RNA, of 5.8 kb, is an unspliced transcript that includes ORF72 and -71 at its 3' end; it initiates at nucleotides (nt) 127880 to 127886 from a promoter lacking recognizable TATA elements. A less abundant mRNA, of 5.4 kb, is a variant of this transcript, in which 336 nt of 5' noncoding information has been removed by RNA splicing. A third, more abundant RNA is generated from the same promoter region via splicing from the common splice donor at nt 127813 to an acceptor 5' to ORF72; this transcript is the presumed mRNA for ORF72, which encodes the viral cyclin D homolog. All three RNAs are 3' coterminal. In situ hybridization analysis with probes that can detect all three transcripts shows that the RNAs are detectable in a large fraction of BCBL-1 cells prior to lytic induction and in >70% of KS spindle cells in primary KS tumors. This confirms that these transcripts are indeed latent RNAs and suggests a role for their products in vital persistence and/or KSHV-associated proliferation.

Original languageEnglish (US)
Pages (from-to)8309-8315
Number of pages7
JournalJournal of virology
Issue number10
StatePublished - Oct 1998


Dive into the research topics of 'A cluster of latently expressed genes in Kaposi's sarcoma-associated herpesvirus'. Together they form a unique fingerprint.

Cite this