Bryan Benjaman A, Dyson Ossie F, Akula Shaw M
Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
J Gen Virol. 2006 Mar;87(Pt 3):519-529. doi: 10.1099/vir.0.81603-0.
Kaposi's sarcoma-associated herpesvirus (KSHV) is the latest addition to the long list of human herpesviruses. Reactivation of latent herpesvirus infections is still a mystery. It was demonstrated recently that the phorbol ester TPA was efficient in inducing a reactivation of KSHV infection in the S phase of the cell cycle. In the present study, flow cytometry-sorted, TPA-induced, KSHV-infected haematopoietic cells (BCBL-1) were used to analyse the expression profiles of cancer-related cellular genes in the S phase of the cell cycle compared with the G0/1 phase by using microarrays. Overall, the S phase of the cell cycle seems to provide KSHV with an apt environment for a productive lytic cycle of infection. The apt conditions include cellular signalling that promotes survivability, DNA replication and lipid metabolism, while blocking cell-cycle progression to M phase. Some of the important genes that were overexpressed during the S phase of the cell cycle compared with the G0/1 phase of TPA-induced BCBL-1 cells are v-myb myeloblastosis (MYBL2), protein kinase-membrane associated tyrosine/threonine 1 (PKMYT1), ribonucleotide reductase M1 polypeptide (RRM1) and peroxisome proliferator-activated receptors delta (PPARD). Inhibition of PKMYT1 expression by the use of specific short interfering RNAs significantly lowered the TPA-induced KSHV lytic cycle of infection. The significance of these and other genes in the reactivation of KSHV is discussed in the following report. Taken together, a flow cytometry-microarray-based method to study the cellular conditions critical for the reactivation of KSHV infection is reported here for the first time.
卡波西肉瘤相关疱疹病毒（KSHV）是人类疱疹病毒众多成员中的最新成员。潜伏性疱疹病毒感染的重新激活仍是一个谜。最近有研究表明，佛波酯TPA能有效诱导细胞周期S期的KSHV感染重新激活。在本研究中，通过使用微阵列，对经流式细胞术分选、TPA诱导的KSHV感染的造血细胞（BCBL-1）进行分析，以比较细胞周期S期与G0/1期癌症相关细胞基因的表达谱。总体而言，细胞周期的S期似乎为KSHV提供了一个有利于其进行有效裂解性感染周期的适宜环境。这些适宜条件包括促进细胞存活、DNA复制和脂质代谢的细胞信号传导，同时阻止细胞周期进展至M期。与TPA诱导的BCBL-1细胞的G0/1期相比，在细胞周期S期过表达的一些重要基因包括v-myb成髓细胞瘤（MYBL2）、蛋白激酶膜相关酪氨酸/苏氨酸1（PKMYT1）、核糖核苷酸还原酶M1多肽（RRM1）和过氧化物酶体增殖物激活受体δ（PPARD）。使用特异性短发夹RNA抑制PKMYT1表达可显著降低TPA诱导的KSHV感染裂解周期。以下报告将讨论这些基因及其他基因在KSHV重新激活中的意义。综上所述，本文首次报道了一种基于流式细胞术-微阵列的方法，用于研究对KSHV感染重新激活至关重要的细胞条件。
