Epstein-Barr virus microRNAs are evolutionarily conserved and differentially expressed.
The pathogenic lymphocryptovirus Epstein-Barr virus (EBV) is shown to express at least 17 distinct microRNAs (miRNAs) in latently infected cells. These are arranged in two clusters: 14 miRNAs are located in the introns of the viral BART gene while three are located adjacent to BHRF1. The BART miRNAs are expressed at high levels in latently infected epithelial cells and at lower, albeit detectable, levels in B cells. In contrast to the tissue-specific expression pattern of the BART miRNAs, the BHRF1 miRNAs are found at high levels in B cells undergoing stage III latency but are essentially undetectable in B cells or epithelial cells undergoing stage I or II latency. Induction of lytic EBV replication was found to enhance the expression of many, but not all, of these viral miRNAs. Rhesus lymphocryptovirus, which is separated from EBV by > or =13 million years of evolution, expresses at least 16 distinct miRNAs, seven of which are closely related to EBV miRNAs. Thus, lymphocryptovirus miRNAs are under positive selection and are likely to play important roles in the viral life cycle. Moreover, the differential regulation of EBV miRNA expression implies distinct roles during infection of different human tissues.
Cai
Xuezhong
X
Center for Virology, Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA.
Schäfer
Alexandra
A
Lu
Shihua
S
Bilello
John P
JP
Desrosiers
Ronald C
RC
Edwards
Rachel
R
Raab-Traub
Nancy
N
Cullen
Bryan R
BR
D002460:Cell Line; D017124:Conserved Sequence; D020031:Epstein-Barr Virus Infections / Q000235:genetics; D019143:Evolution, Molecular; D015870:Gene Expression; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D018143:Lymphocryptovirus / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics*; D008969:Molecular Sequence Data; D014158:Transcription, Genetic; D017735:Virus Latency; D014779:Virus Replication
D035683:MicroRNAs