Epithelial Cells Derived from Swine Bone Marrow Express Stem Cell Markers and Support Influenza Virus Replication In Vitro

ABSTRACT The mechanisms regulating the synthesis of mRNA, cRNA, and viral genomic RNA (vRNA) by the influenza A virus RNA-dependent RNA polymerase are not fully understood. Previous studies in our laboratory have shown that virion-derived viral ribonucleoprotein complexes synthesize both mRNA and cRNA in vitro and early in the infection cycle in vivo. Our continued studies showed that de novo synthesis of cRNA in vitro is more sensitive to the concentrations of ATP, CTP, and GTP than capped-primer-dependent synthesis of mRNA. Using rescued recombinant influenza A/WSN/33 viruses, we now demonstrate that the 3′-terminal sequence of the vRNA promoter dictates the requirement for a high nucleoside triphosphate (NTP) concentration during de novo-initiated replication to cRNA, whereas this is not the case for the extension of capped primers during transcription to mRNA. In contrast to some other viral polymerases, for which only the initiating NTP is required at high concentrations, influenza virus polymerase requires high concentrations of the first three NTPs. In addition, we show that base pair mutations in the vRNA promoter can lead to nontemplated dead-end mutations during replication to cRNA in vivo. Based on our observations, we propose a new model for the de novo initiation of influenza virus replication.

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Cryptoporic acid E from Cryptoporus volvatus inhibits influenza virus replication in vitro

Antiviral Research ◽

10.1016/j.antiviral.2017.02.010 ◽

2017 ◽

Vol 143 ◽

pp. 106-112 ◽

Cited By ~ 5

Author(s):

Li Gao ◽

Jiayuan Han ◽

Jianyong Si ◽

Junchi Wang ◽

Hexiang Wang ◽

...

Keyword(s):

Influenza Virus ◽

Virus Replication ◽

Influenza Virus Replication

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Focal Adhesion Kinase Inhibition Contributes to Tumor Cell Survival and Motility in Neuroblastoma Patient-Derived Xenografts

Scientific Reports ◽

10.1038/s41598-019-49853-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Laura L. Stafman ◽

Adele P. Williams ◽

Raoud Marayati ◽

Jamie M. Aye ◽

Hooper R. Markert ◽

...

Keyword(s):

Stem Cell ◽

Tumor Cell ◽

Cell Survival ◽

Cell Lines ◽

Human Condition ◽

Migration And Invasion ◽

Stem Cell Markers ◽

Cell Markers ◽

Cycle Arrest

Abstract Patient-derived xenografts (PDXs) provide an opportunity to evaluate the effects of therapies in an environment that more closely resembles the human condition than that seen with long-term passage cell lines. In the current studies, we investigated the effects of FAK inhibition on two neuroblastoma PDXs in vitro. Cells were treated with two small molecule inhibitors of FAK, PF-573,228 (PF) and 1,2,4,5-benzentetraamine tetrahydrochloride (Y15). Following FAK inhibition, cell survival and proliferation decreased significantly and cell cycle arrest was seen in both cell lines. Migration and invasion assays were used to determine the effect of FAK inhibition on cell motility, which decreased significantly in both cell lines in the presence of either inhibitor. Finally, tumor cell stemness following FAK inhibition was evaluated with extreme limiting dilution assays as well as with immunoblotting and quantitative real-time PCR for the expression of stem cell markers. FAK inhibition decreased formation of tumorspheres and resulted in a corresponding decrease in established stem cell markers. FAK inhibition decreased many characteristics of the malignant phenotype, including cancer stem cell like features in neuroblastoma PDXs, making FAK a candidate for further investigation as a potential target for neuroblastoma therapy.

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