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151.
Flap endonuclease 1 (FEN1) is a member of the family of structure-specific endonucleases implicated in regulation of DNA damage response and DNA replication. So far, knowledge on the role of FEN1 during viral infections is limited. Previous publications indicated that poxviruses encode a conserved protein that acts in a manner similar to FEN1 to stimulate homologous recombination, double-strand break (DSB) repair and full-size genome formation. Only recently, cellular FEN1 has been identified as a key component for hepatitis B virus cccDNA formation. Here, we report on a novel functional interaction between Flap endonuclease 1 (FEN1) and the human cytomegalovirus (HCMV) immediate early protein 1 (IE1). Our results provide evidence that IE1 manipulates FEN1 in an unprecedented manner: we observed that direct IE1 binding does not only enhance FEN1 protein stability but also phosphorylation at serine 187. This correlates with nucleolar exclusion of FEN1 stimulating its DSB-generating gap endonuclease activity. Depletion of FEN1 and inhibition of its enzymatic activity during HCMV infection significantly reduced nascent viral DNA synthesis demonstrating a supportive role for efficient HCMV DNA replication. Furthermore, our results indicate that FEN1 is required for the formation of DSBs during HCMV infection suggesting that IE1 acts as viral activator of FEN1 in order to re-initiate stalled replication forks. In summary, we propose a novel mechanism of viral FEN1 activation to overcome replication fork barriers at difficult-to-replicate sites in viral genomes. 相似文献
152.
Nicole Endlich Felix Kliewe Frances Kindt Katharina Schmidt Ahmed M. Kotb Nadine Artelt Maja T. Lindenmeyer Clemens D. Cohen Franziska Döring Andreas W. Kuss Kerstin Amann Marcus J. Moeller Nazanin Kabgani Antje Blumenthal Karlhans Endlich 《Journal of cellular and molecular medicine》2018,22(5):2656-2669
153.
154.
Michaela Fels Franziska Lüthje Alice Faux-Nightingale Nicole Kemper 《Journal of applied animal welfare science : JAAWS》2018,21(3):267-282
In this study, the possibility of introducing an elevated platform to a piglet pen was explored as a way of increasing available space and creating functional areas. On the platform, nine different manipulable materials were offered. In four batches, 40 weaned piglets were kept for five weeks in the two-level pen. Video recordings were taken two days per week. In the afternoon, more piglets were on the platform than in the morning or at night (7.2 ± 0.1 vs. 4.9 ± 0.1 vs. 0.6 ± 0.1 piglets/5 minutes; p < .05). The area under the platform was preferred more in the morning and at night than in the afternoon (18.5 ± 0.1 vs. 21.6 ± 0.2 vs. 12.5 ± 0.1 piglets/5 minutes; p < .05). Up to 36 piglets were counted there simultaneously, mainly in the recumbent position. On and under the platform, air velocity and ammonia concentration were within the recommended ranges. The study concluded that a two-level pen is a feasible option to increase space allowance and to create functional areas in a piglet pen. 相似文献
155.
Consequences of Sphaeropsis tip blight disease for the phytohormone profile and antioxidative metabolism of its pine host
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Bin Hu Hitoshi Sakakibara Mikiko Kojima Yumiko Takebayashi Johanna Bußkamp Gitta J. Langer Franziska S. Peters Jörg Schumacher Monika Eiblmeier Jürgen Kreuzwieser Heinz Rennenberg 《Plant, cell & environment》2018,41(4):737-754
Phytopathogenic fungi infections induce plant defence responses that mediate changes in metabolic and signalling processes with severe consequences for plant growth and development. Sphaeropsis tip blight, induced by the endophytic fungus Sphaeropsis sapinea that spreads from stem tissues to the needles, is the most widespread disease of conifer forests causing dramatic economic losses. However, metabolic consequences of this disease on bark and wood tissues of its host are largely unexplored. Here, we show that diseased host pines experience tissue dehydration in both bark and wood. Increased cytokinin and declined indole‐3‐acetic acid levels were observed in both tissues and increased jasmonic acid and abscisic acid levels exclusively in the wood. Increased lignin contents at the expense of holo‐cellulose with declined structural biomass of the wood reflect cell wall fortification by S. sapinea infection. These changes are consistent with H2O2 accumulation in the wood, required for lignin polymerization. Accumulation of H2O2 was associated with more oxidized redox states of glutathione and ascorbate pools. These findings indicate that S. sapinea affects both phytohormone signalling and the antioxidative defence system in stem tissues of its pine host during the infection process. 相似文献
156.
Xiao Guo Xiao-Huang Ren Franziska Eller Ming-Yan Li Ren-Qing Wang Ning Du Wei-Hua Guo 《Acta Physiologiae Plantarum》2018,40(4):79
A greenhouse experiment was conducted in which two leguminous species commonly used in the Yellow River Delta for vegetation restoration, Robinia pseudoacacia and Amorpha fruticosa, were subjected to five salt treatments: 0, 50, 100, 150, and 200 mmol L?1. We aimed to determine which of the two species would be better suited for growth in a saline environment, and whether the acclimation capacity to salinity resulted from an inherently higher phenotypic plasticity. The results showed that salinity affected most growth and biomass parameters but had no effects on most leaf traits and physiological parameters of the two species. Height, relative growth rate of crown area, root biomass, and leaf mass ratio of R. pseudoacacia were reduced by higher salinity, while A. fruticosa was not affected. Chlorophyll a-to-chlorophyll b ratio and total antioxidative capacity of A. fruticosa increased with higher salinity, whereas those of R. pseudoacacia remained unchanged. Root mass ratio and vitamin C concentration of both species were not affected by salinity, whereas vitamin C concentration of A. fruticosa was higher than that of R. pseudoacacia. The root-to-shoot ratio of A. fruticosa was higher than that of R. pseudoacacia in most salt treatments. Of all leaf traits, only leaf area differed between treatments. R. pseudoacacia generally exhibited a greater plasticity than A. fruticosa in response to salinity, but A. fruticosa was more resistant to the higher salinities than R. pseudoacacia, and was thus a better candidate for vegetation restoration in saline areas. 相似文献
157.
The protamine thynnine is an arginine-rich protein approximately 30 amino acids long with a tyrosine in the middle of its sequence. Its fluorescence decay kinetics can be described by a biexponential function with lifetimes of 0.52 and 2.1 ns, with almost equal preexponential factors. The fluorescence quencher CsCl does not affect the short lifetime but shifts the equilibrium between the long and short lifetime toward the short one and reduces the long lifetime. In nature, thynnine is found complexed with chromosomal DNA. In vitro complexes of thynnine with double-stranded (ds) DNA are stable at physiologic ionic strength but dissociate at high NaCl concentration. This dissociation can be monitored by steady-state fluorescence. From the salt concentration dependence of the dissociation of the complex of thynnine with ds-DNA 145 bp long, it can be concluded that only 4 of 21 possible full electrostatic bonds are involved in thynnine-DNA binding. In addition, the binding constant at 1M NaCl is of the order of 106, indicating a strong nonelectrostatic component in arginine-DNA binding. 相似文献
158.
The transcription factor prospero homeobox protein 1 is a direct target of SoxC proteins during developmental vertebrate neurogenesis
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159.
Correction to: Improving the baking quality of bread wheat by genomic selection in early generations
160.
Mathilde Arrivé Franziska Pinker Thalia Salinas‐Giegé Philippe Giegé 《The Plant journal : for cell and molecular biology》2016,87(3):270-280
The maturation of tRNA precursors involves the 5′ cleavage of leader sequences by an essential endonuclease called RNase P. Beyond the ancestral ribonucleoprotein (RNP) RNase P, a second type of RNase P called PRORP (protein‐only RNase P) evolved in eukaryotes. The current view on the distribution of RNase P in cells is that multiple RNPs, multiple PRORPs or a combination of both, perform specialised RNase P activities in the different compartments where gene expression occurs. Here, we identify a single gene encoding PRORP in the green alga Chlamydomonas reinhardtii while no RNP is found. We show that its product, CrPRORP, is triple‐localised to mitochondria, the chloroplast and the nucleus. Its downregulation results in impaired tRNA biogenesis in both organelles and the nucleus. CrPRORP, as a single‐subunit RNase P for an entire organism, makes up the most compact and versatile RNase P machinery described in either prokaryotes or eukaryotes. 相似文献