Abstract
Many DNA virus replication-related proteins are associated with promyelocytic leukemia protein (PML), a component of nuclear domain 10 (ND10), which has been investigated for its potential involvement in viral replication. In the case of Kaposi’s sarcoma-associated herpesvirus (KSHV) lytic gene products, K8 (K-bZIP), ORF59, and ORF75 have been shown to colocalize with PML, but its importance in KSHV lytic replication is still unclear. In this study, we analyzed the functional influence of PML on KSHV latency and lytic replication in KSHV-infected primary effusion lymphoma (PEL) cell lines. Stable PML-knockout (BC3-PMLKO) and PML-overexpressing BC3 cells (BC3PML) were successfully generated and the latency and reactivation status were analyzed. The results demonstrated that neither KSHV latency nor the episome copy number was affected in BC3-PMLKO cells. In the reactivation phase, the expression dynamics of KSHV immediate-early or early lytic proteins such as RTA, K9 (vIRF1), K5, K3, ORF59, and K8 (K-bZIP) were comparable between wild-type, control BC3, and BC3-PMLKO cells. Interestingly, KSHV lytic replication, virion production, and expression of late genes were downregulated in BC3-PMLKO cells and upregulated in BC3PML cells, compared to those in control or wild-type BC3 cells. Moreover, exogenous PML increased the size of the PML dots and recruited additional K8 (K-bZIP) to PML-NBs as dots. Therefore, PML would function as a positive regulator for KSHV lytic DNA replication by recruiting KSHV replication factors such as 8 (K-bZIP) or ORF59 to the PML-NBs.
Highlights
Kaposi’s sarcoma-associated herpesvirus (KSHV), called human herpesvirus 8 (HHV-8), is a large double-stranded DNA virus belonging to the herpesviridae family and γ-herpesvirinae subfamily (Wen and Damania, 2010)
We investigated the expression of DAXX and SP100, components of the PML nuclear bodies (PML-NB) in PML-knockout BC3 cells by Western blot and immunofluorescence assays (IFA) (Figure 1A and Supplementary Figures S1A,B)
Kaposi’s sarcoma-associated herpesvirus maintains dual replication phases in primary effusion lymphoma (PEL) cells: a non-productive episome maintaining latent cycle with limited viral gene expression and a lytic cycle with high expression of viral lytic genes followed by production of progeny viruses (Ye et al, 2011; Uppal et al, 2014)
Summary
Kaposi’s sarcoma-associated herpesvirus (KSHV), called human herpesvirus 8 (HHV-8), is a large double-stranded DNA virus belonging to the herpesviridae family and γ-herpesvirinae subfamily (Wen and Damania, 2010). Importance of PML for KSHV Lytic Replication agent for the development of KS (Chang et al, 1994; Cesarman et al, 1995). It is involved in two important lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman’s disease (MCD) (Cesarman and Knowles, 1999). The virus expresses a few genes along with LANA, such as kaposin, viral cyclin D (v-Cyc/ORF72), viral FLICE inhibitory protein (v-FLIP), K13/ORF71, miRNAs, and vIRF3 (McCormick and Ganem, 2005; Lee et al, 2010; Wen and Damania, 2010)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
