Viral RNPs, mRNA Stability and Export

非编码核糖核酸在携带三种转化疱疹病毒的淋巴细胞中的作用正在研究中。爱泼斯坦-巴尔病毒(EBV)感染和转化人类B细胞，是传染性单核细胞增多症的病原体，并与几种人类癌症有关。疱疹病毒SAIMIRI在新大陆猴子体内诱导致命的淋巴瘤和白血病，并在培养中转化人和猴子的T淋巴细胞，导致成熟的、激活的表型。卡波西肉瘤相关疱疹病毒(KSHV)折磨艾滋病和其他免疫功能低下的患者，与其他疱疹病毒一样，以潜伏形式持续存在，直到裂解阶段激活。在转化细胞中表达的少数病毒基因产物包括两个EBV编码的EBERs和七个H.saimiri编码的HSUR；然而，它们是 对病毒的生长或转变不是必需的。诱导后，KSHV产生PAN，有盖的， 不离开细胞核的多腺苷核糖核酸。这些病毒RNA都相对较小(1.1kb)，丰富，保守，并与宿主蛋白相关-在EBERs和HSURs的情况下-是自身抗原。因此，它们是解剖宿主细胞途径以及病毒转化或裂解生长机制的极佳探针。拟议的实验将测试EBERS、HSURs和PAN可能通过隔离重要宿主蛋白来扰乱细胞新陈代谢的假设，以及它们的RNPs执行一些对病毒至关重要的功能的可能性。蛋白质L22、PKR和La与蛋白质相互作用的分子细节 EBER1将通过结构研究和核苷酸类似干扰作图进行探索。将确定EBER2 RNP的组件。我们将研究EBERs在细胞核和细胞质之间穿梭的可能性，以及它们对宿主基因表达的贡献，通过微阵列分析、微阵列证据表明HSUR1和HSUR2增强转化的T细胞的激活状态将在使用慢病毒载体的救援实验中得到证实，它们与TTP的相互作用及其影响被检测，以及HSURs调节宿主基因表达的水平被确定。将对核内PAN积累所必需的RNA元件和反式作用因子进行表征。PAN在KSHV裂解感染中的功能将通过siRNA敲除和/或基因组PAN缺失来研究，随后将进行互补实验。

The roles of non-coding nuclear RNAs in lymphoid cells harboring three transforming herpesviruses are being investigated. Epstein-Barr virus (EBV) infects and transforms human B cells and is the causative agent of infectious mononucleosis, as well as being associated with several human cancers. Herpesvirus saimiri induces fatal lymphomas and leukemias in New World monkeys and transforms human and monkey T lymphocytes in culture, resulting in a mature, activated phenotype. Kaposi sarcoma-associated herpesvirus (KSHV) afflicts AIDS and other immunocompromised patients and, like other herpesviruses, persists in a latent form until activation of the lytic phase. Among the few viral gene products expressed in transformed cells are the two EBV-encoded EBERs and the seven H. saimiri-encoded HSURS; yet, they are not essential for viral growth or transformation. Upon induction, KSHV produces PAN, a capped, polyadenylated RNA that does not leave the nucleus. These viral RNAs are all relatively small (<1.1 kb), abundant, conserved, and associate with host proteins that - in the case of EBERs and HSURs - are autoantigens. They are therefore excellent probes for dissecting host cell pathways, as well as mechanisms of viral transformation or lytic growth. Proposed experiments will test both the hypothesis that EBERs, HSURs and PAN may perturb cellular metabolism by sequestering important host proteins, and the possibility that their RNPs perform some function critical for the virus. The molecular details of the interactions of protein L22, PKR and La with EBER1 will be probed by structural studies and nucleotide analog interference mapping. Components of the EBER2 RNP will be identified. EBERs will be examined for possible shuttling between the nucleus and cytoplasm, and their contribution to host gene expression assessed by microarray analyses, Microarray evidence that HSURs 1 and 2 enhance the activated state of transformed T cells will be confirmed in rescue experiments using lentiviral vectors, their interaction with TTP and its effects examined, and the level at which HSURs modulate host gene expression determined. RNA elements and trans-acting factors essential for PAN accumulation in the nucleus will be characterized. PAN function in KSHV lytic infection will be investigated by siRNA knockdown and/or genomic PAN deletion, followed by complementation experiments.