No abstract

Protein arginine methyltransferase 6 (PRMT6) is a nuclear enzyme that modifies histone tails. To help elucidate the biological function of PRMT6 in vivo, we generated transgenic mice that ubiquitously express PRMT6 fused to the hormone-binding portion of the estrogen receptor (ER*). The ER*-PRMT6 fusion is unstable and cytoplasmic, but upon systemic treatment with tamoxifen, it becomes stabilized and translocates into the nucleus. As a result, a dramatic increase in the H3R2me2a histone mark is observed. We found that one consequence of induced ER*-PRMT6 activation is increased IL-6 levels. IL-6 expression is regulated by the nuclear factor-kappa B (NF-κB) transcription factor, and PRMT6 functions as a coactivator of this pathway. We show that PRMT6 directly interacts with RelA, and that its overexpression enhances the transcriptional activity of an ectopic NF-κB reporter and endogenously regulates NF-κB target genes. PRMT6 is recruited, by RelA, to selective NF-κB target promoters upon TNF-α stimulation. Moreover, ER*-PRMT6 activation causes RelA accumulation in the nucleus. In summary, we observe that PRMT6 is recruited to chromatin at selective NF-κB target promoters, where it likely impacts the histone code and/or methylates other chromatin-associated proteins to facilitate transcription.

Uracil DNA glycosylases (UNG) are highly conserved proteins that preserve DNA fidelity by catalyzing the removal of mutagenic uracils. All herpesviruses encode a viral UNG (vUNG), and yet the role of the vUNG in a pathogenic course of gammaherpesvirus infection is not known. First, we demonstrated that the vUNG of murine gammaherpesvirus 68 (MHV68) retains the enzymatic function of host UNG in an in vitro class switch recombination assay. Next, we generated a recombinant MHV68 with a stop codon in ORF46/UNG (⌬UNG) that led to loss of UNG activity in infected cells and a replication defect in primary fibroblasts. Acute replication of MHV68⌬UNG in the lungs of infected mice was reduced 100-fold and was accompanied by a substantial delay in the establishment of splenic latency. Latency was largely, yet not fully, restored by an increase in virus inoculum or by altering the route of infection. MHV68 reactivation from latent splenocytes was not altered in the absence of the vUNG. A survey of host UNG activity in cells and tissues targeted by MHV68 indicated that the lung tissue has a lower level of enzymatic UNG activity than the spleen. Taken together, these results indicate that the vUNG plays a critical role in the replication of MHV68 in tissues with limited host UNG activity and this vUNG-dependent expansion, in turn, influences the kinetics of latency establishment in distal reservoirs. IMPORTANCEHerpesviruses establish chronic lifelong infections using a strategy of replicative expansion, dissemination to latent reservoirs, and subsequent reactivation for transmission and spread. We examined the role of the viral uracil DNA glycosylase, a protein conserved among all herpesviruses, in replication and latency of murine gammaherpesvirus 68. We report that the viral UNG of this murine pathogen retains catalytic activity and influences replication in culture. The viral UNG was impaired for productive replication in the lung. This defect in expansion at the initial site of acute replication was associated with a substantial delay of latency establishment in the spleen. The levels of host UNG were substantially lower in the lung compared to the spleen, suggesting that herpesviruses encode a viral UNG to compensate for reduced host enzyme levels in some cell types and tissues. These data suggest that intervention at the site of initial replicative expansion can delay the establishment of latency, a hallmark of chronic herpesvirus infection.A ll herpesvirus genomes encode a homolog of the host uracil DNA glycosylase. If not repaired, uracil misincorporation during DNA replication (1, 2) or conversion upon cytosine deamination (2, 3) will lead to a C:G-to-T:A transition mutation that may have severe consequences for genomic integrity (1). In the host, the recognition and removal of uracils is mediated by members of the uracil DNA glycosylase (UDG) superfamily. UNG2 is the predominant nuclear enzyme responsible for initiating repair (2-6). The role of a seemingly redundant herpesvirus UNG in viral replication is ...

15-Lipoxygenase-2 (15-LOX2) is a human-specific lipid-peroxidizing enzyme most prominently expressed in epithelial cells of normal human prostate but downregulated or completely lost in > 70% of prostate cancer (PCa) cases. Transgenic expression of 15-LOX2 in the mouse prostate surprisingly causes hyperplasia. Here we first provide evidence that 15-LOX2-induced prostatic hyperplasia does not progress to PCa even in p53+/− or p53−/− background. More important, by generating 15-LOX2; Hi-Myc double transgenic (dTg) mice, we show that 15-LOX2 expression inhibits Myc-induced PCa development, such that in the 3-month- and 6-month-old dTg mice, there is a significant reduction in prostate intraneoplasia (PIN) and PCa prevalent in age-matched Hi-Myc prostates. The dTg prostates show increased cell senescence and expression of several senescence-associated molecules, including p27, phosphorylated Rb, and Rb1cc1. We further show that in HPCa, 15-LOX2 and c-Myc manifest reciprocal protein expression patterns. Moreover, RB1CC1 accumulates in senescing normal human prostate (NHP) cells, and in both NHP and RWPE-1 cells, the 15-LOX2 metabolic products 15(S)-HPETE and 15(S)-HETE induce RB1CC1. We finally show that unlike 15-LOX2, RB1CC1 is not lost but rather frequently overexpressed in PCa samples. RB1CC1 knockdown in PC3 cells enhances clonal growth in vitro and tumor growth in vivo. Together, our present studies provide evidence for tumor-suppressive functions for both 15-LOX2 and RB1CC1.

Introduction: Autistic catatonia is an under-recognized debilitating syndrome with long-lasting negative effects for families, healthcare workers, and high-cost to the healthcare system. In this report, we describe two cases of excited catatonia in young men diagnosed with autism. Both endured a delay to diagnosis and difficulty to obtain appropriate treatment.Main concern: Each patient had a change in behavior from their baseline but with differences in severity and onset. The diagnosis in the first patient was made after only 3 months as the change was dramatic and sudden. Yet, despite a confirmed diagnosis, it was difficult to treat as the importance of M-ECT was not recognized by the clinicians. The second patient had been suffering for more than 5 years with a slow progression of worsening aggressive symptoms. The aggression was so uncontrollable that the patient required sedation, intubation and daily ECT. Both suffered from agitation, unprovoked aggression, urinary incontinence, stereotypic, and OCD behaviors and compulsive masturbation.Primary Diagnosis, intervention/outcomes: Both patients were diagnosed with autism, one high-functioning, attending high school and working a part-time job, the second low-functioning, nearly non-verbal, isolated to home and ABA school. The first patient's diagnosis of catatonia was only suspected after five psychiatric admissions and more than 20 medication trials. Lorazepam challenge was effective, he was treated with a short series of ECT but each time the treatments were tapered, the aggression returned. Ultimately, stabilized on weekly ECT. The second patient's behavior was escalating over a 5 month period, to the point, the aggression was uncontrollable. He presented to the ED under involuntary hold and the behavior could not be stabilized to the point that emergent ECT was initiated.Conclusion: Two cases of autistic catatonia diagnosed and treated within a year time span at a small community hospital indicates that this diagnosis is more common than previously recognized. We propose screening all patients with neurodevelopmental disorders with the Bush-Francis and Kanner scales to diagnose and treat them appropriately.