Ebola virus (EBOV) causes a lethal hemorrhagic fever for which there is no approved effective treatment or prevention strategy. EBOV VP35 is a virulence factor that blocks innate antiviral host responses, including the induction of and response to alpha/ beta interferon. VP35 is also an RNA silencing suppressor (RSS). By inhibiting microRNA-directed silencing, mammalian virus RSSs have the capacity to alter the cellular environment to benefit replication. A reporter gene containing specific microRNA target sequences was used to demonstrate that prior expression of wild-type VP35 was able to block establishment of microRNA silencing in mammalian cells. In addition, wild-type VP35 C-terminal domain (CTD) protein fusions were shown to bind small interfering RNA (siRNA). Analysis of mutant proteins demonstrated that reporter activity in RSS assays did not correlate with their ability to antagonize double-stranded RNA (dsRNA)-activated protein kinase R (PKR) or bind siRNA. The results suggest that enhanced reporter activity in the presence of VP35 is a composite of nonspecific translational enhancement and silencing suppression. Moreover, most of the specific RSS activity in mammalian cells is RNA binding independent, consistent with VP35's proposed role in sequestering one or more silencing complex proteins. To examine RSS activity in a system without interferon, VP35 was tested in well-characterized plant silencing suppression assays. VP35 was shown to possess potent plant RSS activity, and the activities of mutant proteins correlated strongly, but not exclusively, with RNA binding ability. The results suggest the importance of VP35-protein interactions in blocking silencing in a system (mammalian) that cannot amplify dsRNA.
CD4+ small/medium pleomorphic T-cell lymphoma is a relatively rare subtype of cutaneous lymphoproliferative disorder with an indolent clinical behavior. The place of this condition among lymphomas is debatable. The authors describe a rare case of the direct association of CD4 small/medium pleomorphic T-cell lymphoma-like solitary nodule with Borrelia burgdorferi infection in a 5-year-old boy, discuss the reactive nature of this condition, and emphasize the importance of clinicopathological correlation.
A 71-year-old woman presented with a persistent asymptomatic lesion on the right upper back that had recently increased in size and changed in color, shape, and texture. The lesion had been present for many years. Physical examination revealed a 1.5-cm, dark brown, hyperkeratotic nodule with no identifiable pigment network on dermatoscopy. The patient had no personal history of melanoma but did have a history of stage I non-small cell lung cancer. A review of systems was noncontributory. A shave biopsy of the lesion was performed. WHAT'S YOUR DIAGNOSIS?a. malignant hidroacanthoma simplex/ pigmented porocarcinoma b. pigmented cutaneous metastasis c. pigmented squamous cell carcinoma d. seborrheic keratosis e. seborrheic keratosis-like melanoma
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.