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Abstract: Influenza A virus represents a significant health and economic threat to both humans and animals worldwide. The polymerase III human H1 promoter was used to express nine short hairpin RNAs (shRNAs) targeting nucleocapsid protein (NP) or the acidic component of polymerase complex (PA) genes of avian influenza virus. Tested shRNAs led to a decrease of up to 400 fold in infective titre and up to 80% in the level of viral NP and PA mRNAs in chicken CH-SAH cells (p <0.05). In mammalian MDCK cells a decrease of up to 106-fold in infective titre, and up to 90% in the level of viral mRNAs (p <0.05) was detected. While RNAi silencing played a major role in viral inhibition, transfection of any plasmid induced an antiviral interferon response in MDCK cells. In CH-SAH cells, no induction of IFN response was observed by constructs, and the IFN response was suppressed by influenza virus infection. Simultaneous induction of RNAi and IFN responses in CH-SAH cells resulted in 18,500-fold decrease in infective titre (p <0.05). We also identified novel efficient and conserved RNAi target site in the NP gene which can be used in antiviral cocktails of shRNAs to block the escape of influenza virus. [Copyright &y& Elsevier]

Abstract: Hyperforin is a pharmacologically active constituent of Hypericum perforatum (St. John’s wort). In vitro cultures of this medicinal plant were found to contain hyperforin and three related polyprenylated acylphloroglucinol derivatives. The accumulation of these compounds was coupled to shoot regeneration, with secohyperforin being the major constituent in morphogenic cultures. The structure of secohyperforin was elucidated online by LC-DAD, -MS, and -NMR. In multiple shoot cultures, the ratio of hyperforin to secohyperforin was strongly influenced by the phytohormones N 6-benzylaminopurine (BAP) and naphthalene-1-acetic acid (NAA). While increasing concentrations of BAP stimulated the formation of hyperforin, increasing concentrations of NAA elevated the level of secohyperforin. No differential stimulation was observed after elicitor treatment. Hyperforin and secohyperforin are proposed to arise from a branch point in the biosynthetic pathway. [Copyright &y& Elsevier]

Unravelling how species communities change along environmental gradients requires a dual understanding: the direct responses of the species to their abiotic surroundings and the indirect variation of these responses through biotic interactions. Here, we focus on the interactive relationships between plants and their symbiotic root‐associated fungi (RAF) along stressful abiotic gradients. We investigate whether variations in RAF community composition along altitudinal gradients influence plant growth at high altitudes, where both plants and fungi face harsher abiotic conditions. We established a translocation experiment between pairs of Bistorta vivipara populations across altitudinal gradients. To separate the impact of shifting fungal communities from the overall influence of changing abiotic conditions, we used a root barrier to prevent new colonization by RAF following translocation. To characterize the RAF communities, we applied DNA barcoding to the root samples. Through the utilization of joint species distribution modelling, we assessed the relationship between changes in plant functional traits resulting from experimental treatments and the corresponding changes in the RAF communities. Our findings indicate that RAF communities influence plant responses to stressful abiotic conditions. Plants translocated from low to high altitudes grew more when they were able to associate with the resident high‐altitude RAF compared to those plants that were not allowed to associate with the resident RAF. We conclude that interactions with RAF impact how plants respond to stressful abiotic conditions. Our results provide experimental support that interactions with RAF improve plant stress tolerance to altitudinal stressors such as colder temperatures and less nutrient availability. [ABSTRACT FROM AUTHOR]