The P6 protein of Rice yellow stunt rhabdovirus (RYSV) is a virion structural protein that can be phosphorylated in vitro. However its exact function remains elusive. We found that P6 enhanced the virulence of Potato virus X (PVX) in Nicotiana benthamiana and N. tabacum plants, suggesting that it might function as a suppressor of RNA silencing. We examined the mechanism of P6-mediated silencing suppression by transiently expressing P6 in both N. benthamiana leaves and rice protoplasts. Our results showed that P6 could repress the production of secondary siRNAs and inhibit systemic green fluorescent protein RNA silencing but did not interfere with local RNA silencing in N. benthamiana plants or in rice protoplasts. Intriguingly, P6 and RDR6 had overlapping subcellular localization and P6 bound both rice and Arabidopsis RDR6 in vivo. Furthermore, transgenic rice plants expressing P6 showed enhanced susceptibility to infection by Rice stripe virus. Hence, we propose that P6 is part of the RYSV's counter-defense machinery against the plant RNA silencing system and plays a role mainly in affecting RDR6-mediated secondary siRNA synthesis. Our work provides a new perspective on how a plant-infecting nucleorhabdovirus may counteract host RNA silencing-mediated antiviral defense.

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The race to survive between plants and pathogens has been neverending during the long history of their co-evolution. Plants are exposed to a wide range of environmental microbes and have evolved sophisticated immune systems to defend against potential pathogens, including two layers of immunity: pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity

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Background: Anti-silencing function 1B histone chaperone (ASF1B) has been identified to compensate for growth defects and sensitivity to replication stress. Recent studies demonstrated that ASF1B plays an important role in the tumorigenesis of human cancer. However, its relationship with clinical outcome of cervical carcinoma is unknown. Therefore, we aimed to investigate the expression pattern and clinical significance of ASF1B in cervical cancer and its role in regulating invasion and metastasis of cervical cancer cell lines.Methods: Expression of ASF1B was analyzed in eight cervical cancer cell lines, and eight pairs of cervical cancer samples and the adjacent normal specimens, using real-time PCR and western blotting. Immunohistochemistry was used to analyze ASF1B expression in paraffin-embedded tissues from 147 cervical cancer patients. The association between ASF1B expression levels, clinicopathological parameters, and prognosis was analyzed statistically. Moreover, the biological function and potential mechanism of ASF1B in migration and invasion of cervical cancer cells were investigated by in vitro experiments and Western blotting.Results: ASF1B mRNA and protein levels were overexpressed in cervical cancer cell lines and tissues compared with normal cells and adjacent normal cervical specimens. In paraffin-embedded cervical carcinoma tissues, upregulation of ASF1B protein was identified in 86 (58.5%) of 147 cases, and was remarkably associated with pelvic lymph node metastasis, lymphovascular space involvement, property of surgical margin, FIGO stage, sqaumous cell carcinoma antigen and poor survival. Cox analysis demonstrated that ASF1B expression was an independent risk predictor for survival in patients with cervical carcinoma. Additionally, down-regulation of ASF1B significantly inhibited invasion and migration of cervical cancer cells. Moreover, it was demonstrated that ASF1B regulated the Wnt/β-catenin pathway in cervical carcinoma.Conclusions: This study suggested that ASF1B might serve as a important prognostic biomarker and therapeutic target for patients with cervical carcinoma.

Purposes: Currently, most researchers mainly analyzed COVID-19 pneumonia visually or qualitatively, probably somewhat time-consuming and not precise enough. This study aimed to excavate more information, such as differences in distribution, density, and severity of pneumonia lesions between males and females in a specific age group using artificial intelligence (AI)-based CT metrics. Besides, these metrics were incorporated into a clinical regression model to predict the short-term outcome.Methods: The clinical, laboratory information and a series of HRCT images from 49 patients, aged from 20 to 50 years and confirmed with COVID-19, were collected. The volumes and percentages of infection (POI) among bilateral lungs and each bronchopulmonary segment were extracted using uAI-Discover-NCP software (version R001). The POI in three HU ranges, (i.e. <-300, -300~49 and ≥50 HU representing ground-glass opacity (GGO), mixed opacity and consolidation), were also extracted. Hospital stay was predicted with several POIs after adjusting days from illness onset to admission, leucocytes, lymphocytes, c-reactive protein, age and gender using a multiple linear regression model.Results: Right lower lobes had the highest POI, followed by left lower lobes, right upper lobes, middle lobes and left upper lobes. The distributions in lung lobes and segments were different between the sexes. Men had a higher total POI and GGO of the lungs, but less consolidation than women in initial CT (all p<0.05). The total POI, percentage of consolidation on initial CT and changed POI were positively correlated with hospital stay in the model.Conclusion: Both men and women had characteristic distributions in lung lobes and bronchopulmonary segments. AI-based CT quantitative metrics can provide more precise information regarding lesion distribution and severity to predict clinical outcome.