title: Kaposi's sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen regulates the KSHV epigenome by association with the histone demethylase KDM3A.
abstract: Kaposi's sarcoma-associated herpesvirus (KSHV) latent genomes are tethered to host histones to form a minichromosome also known as an "episome." Histones, which are core components of chromatin, are heavily modified by various histone-targeting enzymes. Posttranslational modifications of histones significantly influence accessibility of transcriptional factors and thus have profound effects on gene expression. Recent studies showed that epigenetic marks on the KSHV episome are well organized, exemplified by the absence of histone H3 lysine 9 (H3K9) methylation, a heterochromatic histone mark, from immediate early and latent gene promoters in naturally infected cells. The present study revealed a mechanistic insight into KSHV epigenome regulation via a complex consisting of LANA and the H3K9me1/2 histone demethylase JMJD1A/KDM3A. This complex was isolated from HeLa cell nuclear extracts stably expressing LANA and was verified by coimmunoprecipitation analyses and with purified proteins. LANA recruitment sites on the KSHV genome inversely correlated with H3K9me2 histone marks in naturally infected cells, and methylation of H3K9 significantly inhibited LANA binding to the histone H3 tail. Chromatin immunoprecipitation coupled with KSHV tiling arrays identified the recruitment sites of the complex, while depletion of LANA expression or overexpression of a KDM3A binding-deficient mutant decreased KDM3A recruitment to the KSHV genome. Finally, ablation of KDM3A expression from latently KSHV-infected cells significantly inhibited KSHV gene expression, leading to decreased KSHV replication during reactivation. Taken together, our results suggest that LANA may play a role in regulation of epigenetic marks on the KSHV genome, which is in part through association with the histone demethylase KDM3A.
authors.affiliation: Department of Dermatology, University of California, Davis, School of Medicine, Sacramento, California, USA.
authors.forename: Kevin Y
authors.initials: KY
authors.lastname: Kim
authors.forename: Steve B
authors.initials: SB
authors.lastname: Huerta
authors.forename: Chie
authors.initials: C
authors.lastname: Izumiya
authors.forename: Don-Hong
authors.initials: DH
authors.lastname: Wang
authors.forename: Anthony
authors.initials: A
authors.lastname: Martinez
authors.forename: Bogdan
authors.initials: B
authors.lastname: Shevchenko
authors.forename: Hsing-Jien
authors.initials: HJ
authors.lastname: Kung
authors.forename: Mel
authors.initials: M
authors.lastname: Campbell
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Izumiya
mesh_terms: D000956:Antigens, Viral / Q000235:genetics / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D004261:DNA Replication; D044127:Epigenesis, Genetic; D015967:Gene Expression Regulation, Viral / Q000235:genetics*; D016679:Genome, Viral; D057809:HEK293 Cells; D006367:HeLa Cells; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006657:Histones / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D017735:Virus Latency
chemical_list: D000956:Antigens, Viral; D006657:Histones; D009687:Nuclear Proteins; C109540:latency-associated nuclear antigen; D056484:Jumonji Domain-Containing Histone Demethylases; C530247:KDM3A protein, human