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Transposable elements (TEs) have long been regarded as ‘selfish DNA’, and are generally silenced by epigenetic mechanisms. However, work in the past decade has identified positive roles for TEs in generating genomic novelty and diversity in plants. In particular, recent studies suggested that TE-induced epigenetic alterations and modification of gene expression contribute to phenotypic variation and adaptation to geography or stress. These findings have led many to regard TEs, not as junk DNA, but as sources of control elements and genomic diversity. As a staple food crop and model system for genomic research on monocot plants, rice ( Oryza sativa ) has a modest-sized genome that harbors massive numbers of DNA transposons (class II transposable elements) scattered across the genome, which may make TE regulation of genes more prevalent. In this review, we summarize recent progress in research on the functions of rice TEs in modulating gene expression and creating new genes. We also examine the contributions of TEs to phenotypic diversity and adaptation to environmental conditions. [ABSTRACT FROM AUTHOR]

Cytosine methylation in plants occurs in the mCG, mCHG, and mCHH (where H = A, T, or C) sequence contexts and specific pathways maintain methylation in each one. A recent publication revealed that substantial heterogeneity of methylated cytosine levels exists in the CHG/CHH trinucleotide contexts, which is associated with chromomethyltranferase functions in the maintenance of methylation. [ABSTRACT FROM AUTHOR]

• For the first time, quaternary ammonium salt ionic liquid collector was synthesized and used in the flotation test of bauxite. • The synthesized ionic liquid collector can achieve the simultaneous desulfurization and desiliconization. • The optimal results that the recovery rate of Al 2 O 3 is 50.8%, Al/Si is 3.24, and the grade of S is 0.67% can be obtained in the concentrate. An quaternary ammonium ionic liquid (1401) was synthesized through tetradecyl dimethyl benzyl ammonium chloride and sodium isobutyl xanthate. Firstly, it was used as a flotation collector for reverse flotation of silicates and sulfur from diaspore-type high-sulfur and high silicon bauxite. Results demonstrated that maximum Al 2 O 3 recovery of 50.8% were achieved, the sulfur content and the ratio of A/S were 0.65% and 3.24. The results showed the 1401 has a stronger collecting ability and selectivity for diaspore compared with dodecyl trimethyl ammonium chloride and N-butyl xanthate. The adsorption mechanism of 1401 on the surface of diaspore, kaolinite and pyrite was studied by Fourier transform infrared spectroscopy (FTIR), zeta potential and X-ray photoelectron spectroscopy (XPS) analysis. Results indicated that physical adsorption was occurred between the 1401 and the surface of diaspore, kaolinite, and the adsorption amount on the surface of kaolinite is much greater than that of diaspore. And the chemisorption between the 1401 and pyrite was occurred and suggested that 1401 was preferred to adsorb on the surface of diaspore and pyrite. These results indicate that the quaternary ammonium ionic liquid 1401 can be used as the collector for reverse flotation of diaspore, providing new ideas for the utilization of bauxite. [ABSTRACT FROM AUTHOR]