KSHV encoded LANA recruits Nucleosome Assembly Protein NAP1L1 for regulating viral DNA replication and transcription.
The establishment of latency is an essential for lifelong persistence and pathogenesis of Kaposi's sarcoma-associated herpesvirus (KSHV). Latency-associated nuclear antigen (LANA) is the most abundantly expressed protein during latency and is important for viral genome replication and transcription. Replication-coupled nucleosome assembly is a major step in packaging the newly synthesized DNA into chromatin, but the mechanism of KSHV genome chromatinization post-replication is not understood. Here, we show that nucleosome assembly protein 1-like protein 1 (NAP1L1) associates with LANA. Our binding assays revealed an association of LANA with NAP1L1 in KSHV-infected cells, which binds through its amino terminal domain. Association of these proteins confirmed their localization in specific nuclear compartments of the infected cells. Chromatin immunoprecipitation assays from NAP1L1-depleted cells showed LANA-mediated recruitment of NAP1L1 at the terminal repeat (TR) region of the viral genome. Presence of NAP1L1 stimulated LANA-mediated DNA replication and persistence of a TR-containing plasmid. Depletion of NAP1L1 led to a reduced nucleosome positioning on the viral genome. Furthermore, depletion of NAP1L1 increased the transcription of viral lytic genes and overexpression decreased the promoter activities of LANA-regulated genes. These results confirmed that LANA recruitment of NAP1L1 helps in assembling nucleosome for the chromatinization of newly synthesized viral DNA.
Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA.
Namrata
N
Gupta
Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA.
Suhani
S
Thakker
Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV 89557, USA.
Subhash C
SC
Verma
D000956:Antigens, Viral / Q000737:chemistry / Q000378:metabolism*; D045744:Cell Line, Tumor; D004261:DNA Replication; D004279:DNA, Viral / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D015967:Gene Expression Regulation, Viral; D016679:Genome, Viral; D057809:HEK293 Cells; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D056490:Nucleosome Assembly Protein 1 / Q000737:chemistry / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D000072417:Protein Domains; D040901:Proteomics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D015854:Up-Regulation / Q000235:genetics; D014779:Virus Replication
D000956:Antigens, Viral; D004279:DNA, Viral; C533557:NAP1L1 protein, human; D009687:Nuclear Proteins; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes; D012333:RNA, Messenger; C109540:latency-associated nuclear antigen