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【Background and objective】 Drought and soil salinization are two common abiotic stresses facing agricultural production worldwide. Plants develop various strategies to grow under these stresses, and the purpose of this paper is to investigate how winter wheat at seedling stage adjusts the hydraulic conductance of its roots as a response to change in water and salt stresses. 【Method】 The experiment was conducted in hydroponic culture, using the ultra-high variety Yannong 1212 as the model plant. Water stress was created by polyethylene glycol (PEG) and NaCL was used as a proxy for soil salinization. There were three treatments: 2% of PEG6000, 0.1% of NaCl, and 2% of PEG6000+0.1% NaCl. Wheat grown in Hoagland nutrient solution without abiotic stresses was taken as the control. For each treatment, we measured the root hydraulic conductivity and analyzed its relationship with environmental factors using stepwise regression method. 【Result】 ① Water stress and salt stress, working alone or in combination, reduced plant height and leaf area significantly, though the level of the significance varied with treatment. ② Compared with the control, water stress and salt stress working alone increased root-shoot ratio by 12% and 14% respectively, while their combination reduced this ratio by 6%; ③ Salt stress and water stress, working separately or in combination, increased Na+/K+ ratio in both leaves and roots, despite that the effect of water stress was not significant. ④ Water stress and salt stress and their combination significantly reduced total nitrogen content in the leaves, and reduced the root hydraulic conductivity by 58%, 51% and 93%, respectively, compared with the control. 【Conclusion】 Water and salt stresses reduced root hydraulic conductivity of the wheat at seedling stage, and the leaf area was positively correlated with the root hydraulic conductivity.

Objective To investigate the effects and mechanisms of miR-198 on the proliferation, apoptosis and invasion of cervical cancer cells. Methods HeLa cells were transfected with miR-198 mimic and the mRNA levels between miR-198 and mitogen-activated protein kinase 1(MAPK1) were measured by qRT-PCR. The relationship of miR-198 and MAPK1 was determined by luciferase reporter assay. pcDNA3.0-MAPK1 (pc-MAPK1) and miR-198 mimic transfection was performed, and cell proliferation, apoptosis and invasion abilities were measured by CCK-8 assay, flow cytometry and Transwell assay, respectively. Western blot was performed for protein levels. Results The level of miR-198 was increased and the mRNA level of MAPK1 was decreased by miR-198 mimic. The result of luciferase reporter assay indicated that there was binding site of MAPK1 on miR-198. Overexpression of miR-198 significantly inhibited the proliferation and invasion, and induced the apoptosis of HeLa cells. In addition, miR-198 mimic down-regulated the expressions of ribosomal S6 kinase 2 (RSK2), c-Myc and c-fos. pc-MAPK1 attenuated the effects of miR-198 mimic on cell proliferation, apoptosis, invasion and downstream proteins expression of MAPK1 in HeLa cells. Conclusion Overexpression of miR-198 inhibits the proliferation, invasion and induces the apoptosis of cervical cancer cells through targeting MAPK1.

This study assessed the influence of information literacy training on graduate students' self-rated ability to search using academic databases and the internet to find information, as well as their objective information literacy skills through a survey in 2017 at the University of Windsor. After controlling for a comprehensive set of covariates, there was not a statistically significant difference in self-rated searching ability between students with training and those without any training. However, the trained students' average objective assessment scores in the five dimensions of information literacy were significantly higher than those of students without any training at the significant level [alpha]=0.05.

Transcription initiation has long been considered a primary regulatory step in gene expression. Recent work, however, shows that downstream events, such as transcription elongation, can also play important roles.1-3 A well-characterized example from animals is promoter-proximal pausing, where transcriptionally engaged Pol II accumulates 30-50 bp downstream of the transcription start site (TSS) and is thought to enable rapid gene activation.2 Plants do not make widespread use of promoter-proximal pausing; however, in a phenomenon known as 3' pausing, a significant increase in Pol II is observed near the transcript end site (TES) of many genes.4-6 Previous work has shown that 3' pausing is promoted by the BORDER (BDR) family of negative transcription elongation factors. Here we show that BDR proteins play key roles in gene repression. Consistent with BDR proteins acting to slow or pause elongating Pol II, BDR-repressed genes are characterized by high levels of Pol II occupancy, yet low levels of mRNA. The BDR proteins physically interact with FPA,7 one of approximately two dozen genes collectively referred to as the autonomous floral-promotion pathway,8 which are necessary for the repression of the flowering time gene FLOWERING LOCUS C (FLC).9-11 In early-flowering strains, FLC expression is repressed by repressive histone modifications, such as histone H3 lysine 27 trimethylation (H3K27me3), thereby allowing the plants to flower early. These results suggest that the repression of transcription elongation by BDR proteins may allow for the temporary pausing of transcription or facilitate the long-term repression of genes by repressive histone modifications.

Background The growth habit (GH), also named the branching habit, is an important agronomic trait of peanut and mainly determined by the lateral branch angle (LBA). The branching habit is closely related to peanut mechanized farming, pegging, yield, and disease management. Objectives However, the molecular basis underlying peanut LBA needs to be uncovered. Methods In the present study, an erect branching peanut mutant, eg06g, was obtained via 60Co γ-ray-radiating mutagenesis of a spreading-type peanut cultivar, Georgia-06G (G06G). RNA-seq was performed to compare the transcriptome variation of the upper sides and lower sides of the lateral branch of eg06g and G06G. Results In total, 4908 differentially expressed genes (DEGs) and 5833 DEGs were identified between eg06g and G06G from the lower sides and upper sides of the lateral branch, respectively. GO, KEGG, and clustering enrichment analysis indicated that the carbohydrate metabolic process, cell wall organization or biogenesis, and plant hormone signal transduction were mainly enriched in eg06g. Conclusions Further analysis showed that the genes involved in starch biosynthesis were upregulated in eg06g, which contributed to amyloplast sedimentation and gravity perception. Auxin homeostasis and transport-related genes were found to be upregulated in eg06g, which altered the redistribution of auxin in eg06g and in turn triggered apoplastic acidification and activated cell wall modification-related enzymes, leading to tiller angle establishment through the promotion of cell elongation at the lower side of the lateral branch. In addition, cytokinin and GA also demonstrated synergistic action to finely regulate the formation of peanut lateral branch angles. Collectively, our findings provide new insights into the molecular regulation of peanut LBA and present genetic materials for breeding peanut cultivars with ideotypes. [ABSTRACT FROM AUTHOR]