In eukaryotic cells, the oluble-ethylmaleimide-ensitive actor (NSF)ttachment protein ceptor (SNARE) proteins comprise the minimal machinery that triggers fusion of transport vesicles with their target membranes. Comparative studies revealed that genes encoding the components of the SNARE system are highly conserved in yeast, insect, and human genomes. Upon infection of insect cells by the virus Autographa californica multiple nucleopolyhedrovirus (AcMNPV), the transcript levels of most SNARE genes initially were upregulated. We found that overexpression of dominant-negative (DN) forms of NSF or knockdown of the expression of NSF, the key regulator of the SNARE system, significantly affected infectious AcMNPV production. In cells expressing DN NSF, entering virions were trapped in the cytoplasm or transported to the nucleus with low efficiency. The presence of DN NSF also moderately reduced trafficking of the viral envelope glycoprotein GP64 to the plasma membrane but dramatically inhibited production of infectious budded virions (BV). Transmission electron microscopy analysis of infections in cells expressing DN NSF revealed that progeny nucleocapsids were retained in a perinuclear space surrounded by inner and outer nuclear membranes. Several baculovirus conserved (core) proteins (Ac76, Ac78, GP41, Ac93, and Ac103) that are important for infectious budded virion production were found to associate with NSF, and NSF was detected within the assembled BV. Together, these data indicate that the cellular SNARE system is involved in AcMNPV infection and that NSF is required for efficient entry and nuclear egress of budded virions of AcMNPV. Little is known regarding the complex interplay between cellular factors and baculoviruses during viral entry and egress. Here, we examined the cellular SNARE system, which mediates the fusion of vesicles in healthy cells, and its relation to baculovirus infection. Using a DN approach and RNA interference knockdown, we demonstrated that a general disruption of the SNARE machinery significantly inhibited the production of infectious BV of AcMNPV. The presence of a DN NSF protein resulted in low-efficiency entry of BV and the retention of progeny nucleocapsids in the perinuclear space during egress. Combined with these effects, we also found that several conserved (core) baculovirus proteins closely associate with NSF, and these results suggest their involvement in the egress of BV. Our findings are the first to demonstrate that the SNARE system is required for efficient entry of BV and nuclear egress of progeny nucleocapsids of baculoviruses.
Background: Malignant melanoma (MM) generally presents as a primary neoplasm of the skin, and most MM cases of the respiratory system are metastatic. Primary MM of the lung (PMML) is quite rare, and its diagnosis is relatively difficult. Case presentation: We report the case of a 57-year-old male patient with PMML who denied any history of tumours. His initial complaint was frequent coughs with bloody sputum for 4 days. Chest radiography demonstrated a highdensity shadow in the lower lobe of the right lung, which was suspected to be a large space-occupying lesion on subsequent computed tomography (CT) and to be a hypermetabolic tumour by positron emission tomography-CT. To confirm the diagnosis, exploratory surgery was performed. Finally, we confirmed the diagnosis of PMML. Conclusions: PMML is extremely rare and easily misdiagnosed as lung cancer. Because of its morphological and immunophenotypic variations, the diagnosis of PMML remains difficult. This case report discusses the diagnosis and case management of a patient while referring to the existing literature.
The tumor microenvironment (TME) directly determines patients' outcomes and therapeutic efficiencies. An in‐depth understanding of the TME is required to improve the prognosis of patients with cervical cancer (CC). This study conducted single‐cell RNA and TCR sequencing of six‐paired tumors and adjacent normal tissues to map the CC immune landscape. T and NK cells were highly enriched in the tumor area and transitioned from cytotoxic to exhaustion phenotypes. Our analyses suggest that cytotoxic large‐clone T cells are critical effectors in the antitumor response. This study also revealed tumor‐specific germinal center B cells associated with tertiary lymphoid structures. A high‐germinal center B cell proportion in patients with CC is predictive of improved clinical outcomes and is associated with elevated hormonal immune responses. We depicted an immune‐excluded stromal landscape and established a joint model of tumor and stromal cells to predict CC patients' prognosis. The study revealed tumor ecosystem subsets linked to antitumor response or prognosis in the TME and provides information for future combinational immunotherapy.
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.