An ultrastructural study of pyrenoids inLeptosiropsis torulosa

Summary The ultrastructure of the mature pyrenoid of the chaetophoracean algaLeptosiropsis torulosa is unlike any described for the green algae. The nucleus is surrounded by the pyrenoid, with only the endoplasmic reticulum interrupting the encircling pyrenoid. The pyrenoid possesses only the appressed plastid membranes that are in contact with the nucleus, with no traversing thylakoids present.     

Removal of heavy metals from industrial wastewater using microbial fuel cell

Removal efficiency of gold from a solution of pure tetrachloroaurate ions was investigated using microbial fuel cell (MFC) technology. The effects of type of catholyte solution and initial gold concentration on the removal efficiency were considered. Due to its presence at high levels in the gold wastewater, the effect of copper ions on the removal efficiency of the gold ions was also studied. The effects of pH and initial biomass concentration on the gold removal efficiency was also determined. The results showed that after 5 h contact time, 95% of gold removal efficiency from a wastewater containing 250 ppm of initial gold ions at ambient temperature using 80 g/L yeast concentration was achieved. After 48 h of the cell''s operation under the same condition, 98.86% of AuCl₄ ^– ions were successfully removed from the solution. At initial gold concentration in the waste solution of 250 ppm, pH 2, and initial yeast concentration of 80 g/L, 100% removal efficiency of the gold was achieved. On the other hand, the most suitable condition for copper removal was found at a pH of 5.2, where 53% removal efficiency from the waste solution was accomplished.     

Trade-offs in the genetic control of functional and nutritional quality traits in UK winter wheat

A complex network of trade-offs exists between wheat quality and nutritional traits. We investigated the correlated relationships among several milling and baking traits as well as mineral density in refined white and whole grain flour. Our aim was to determine their pleiotropic genetic control in a multi-parent population over two trial years with direct application to practical breeding. Co-location of major quantitative trait loci (QTL) and principal component based multi-trait QTL mapping increased the power to detect QTL and revealed pleiotropic effects explaining many complementary and antagonistic trait relationships. High molecular weight glutenin subunit genes explained much of the heritable variation in important dough rheology traits, although additional QTL were detected. Several QTL, including one linked to the TaGW2 gene, controlled grain size and increased flour extraction rate. The semi-dwarf Rht-D1b allele had a positive effect on Hagberg falling number, but reduced grain size, specific weight, grain protein content and flour water absorption. Mineral nutrient concentrations were lower in Rht-D1b lines for many elements, in wholemeal and white flour, but potassium concentration was higher in Rht-D1b lines. The presence of awns increased calcium content without decreasing extraction rate, despite the negative correlation between these traits. QTL were also found that affect the relative concentrations of key mineral nutrients compared to phosphorus which may help increase bioavailability without associated anti-nutritional effects of phytic acid. Taken together these results demonstrate the potential for marker-based selection to optimise trait trade-offs and enhance wheat nutritional value by considering pleiotropic genetic effects across multiple traits.Subject terms: Plant breeding, Quantitative trait, Genetic variation     

Antagonism of microRNA-122 in mice by systemically administered LNA-antimiR leads to up-regulation of a large set of predicted target mRNAs in the liver

MicroRNA-122 (miR-122) is an abundant liver-specific miRNA, implicated in fatty acid and cholesterol metabolism as well as hepatitis C viral replication. Here, we report that a systemically administered 16-nt, unconjugated LNA (locked nucleic acid)-antimiR oligonucleotide complementary to the 5′ end of miR-122 leads to specific, dose-dependent silencing of miR-122 and shows no hepatotoxicity in mice. Antagonism of miR-122 is due to formation of stable heteroduplexes between the LNA-antimiR and miR-122 as detected by northern analysis. Fluorescence in situ hybridization demonstrated uptake of the LNA-antimiR in mouse liver cells, which was accompanied by markedly reduced hybridization signals for mature miR-122 in treated mice. Functional antagonism of miR-122 was inferred from a low cholesterol phenotype and de-repression within 24 h of 199 liver mRNAs showing significant enrichment for miR-122 seed matches in their 3′ UTRs. Expression profiling extended to 3 weeks after the last LNA-antimiR dose revealed that most of the changes in liver gene expression were normalized to saline control levels coinciding with normalized miR-122 and plasma cholesterol levels. Combined, these data suggest that miRNA antagonists comprised of LNA are valuable tools for identifying miRNA targets in vivo and for studying the biological role of miRNAs and miRNA-associated gene-regulatory networks in a physiological context.     

Genetic Screens Identify Host Factors for SARS-CoV-2 and Common Cold Coronaviruses

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