title: The KSHV RNA regulator ORF57: target specificity and its role in the viral life cycle.
abstract: Kaposi's sarcoma-associated herpesvirus (KSHV) encodes ORF57, which enhances the expression of intron-less KSHV genes on multiple post-transcriptional levels mainly affecting RNA stability and export to the cytoplasm. Yet, it remains elusive how ORF57 recognizes viral RNAs and discriminates them from cellular messenger RNAs (mRNAs). Although one common binding motif on three separate KSHV RNAs has been described, most other lytic genes lack this sequence element. In this article we will review the sequence requirements for ORF57 to enhance RNA expression and discuss a model how ORF57 achieves specificity for viral RNAs. Finally, the role of ORF57 is integrated into the viral life cycle as a complex interplay with other viral and host factors and with implications for cellular gene expression.
authors.affiliation: Institute for Virology, Hannover Medical School, Hannover, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Vogt
authors.affiliation: Institute for Virology, Hannover Medical School, Hannover, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Bohne
mesh_terms: D015967:Gene Expression Regulation, Viral; D019288:Herpesvirus 8, Human / Q000502:physiology*; D006801:Humans; D011485:Protein Binding; D012323:RNA Processing, Post-Transcriptional; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism; D020218:Response Elements; D054334:Viral Regulatory and Accessory Proteins / Q000737:chemistry / Q000378:metabolism*; D014779:Virus Replication
chemical_list: C000598480:ORF57 protein, human herpesvirus 8; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D054334:Viral Regulatory and Accessory Proteins