Cloning and characterization of microRNAs from wheat (Triticum aestivum L.)

A small RNA library was used to identify 58 miRNAs from 43 miRNA families from wheat (Triticum aestivum L.), and 46 potential targets were predicted

Ladder-like energy-relaying exciplex enables 100% internal quantum efficiency of white TADF-based diodes in a single emissive layer.

Development of white organic light-emitting diodes based on purely thermally activated delayed fluorescence with a single-emissive-layer configuration has been a formidable challenge. Here, we report the rational design of a donor-acceptor energy-relaying exciplex and its utility in fabricating single-emissive-layer, thermally activated delayed fluorescence-based white organic light-emitting diodes that exhibit 100% internal quantum efficiency, 108.2 lm W-1 power efficiency, and 32.7% external quantum efficiency. This strategy enables thin-film fabrication of an 8 cm × 8 cm thermally activated delayed fluorescence white organic light-emitting diodes (10 inch2) prototype with 82.7 lm W-1 power efficiency and 25.0% external quantum efficiency. Introduction of a phosphine oxide-based acceptor with a steric group to the exciplex limits donor-acceptor triplet coupling, providing dual levels of high-lying and low-lying triplet energy. Transient spectroscopic characterizations confirm that a ladder-like energy relaying occurs from the high-lying triplet level of the exciplex to a blue emitter, then to the low-lying triplet level of the phosphine oxide acceptor, and ultimately to the yellow emitter. Our results demonstrate the broad applicability of energy relaying in multicomponent systems for exciton harvesting, providing opportunities for the development of third-generation white organic light-emitting diode light sources

Data from: Genome-wide mapping of targets of maize histone deacetylase hda101 reveals its function and regulatory mechanism during seed development

Histone deacetylases (HDACs) control histone acetylation levels by removing acetyl group from lysine residues. Maize (Zea mays) HDAC HDA101 influences several aspects of development, including kernel size; however, the molecular mechanism by which HDA101 affects kernel development remains unknown. In this study, we find HDA101 regulates the expression of transfer cell-specific genes, suggesting their mis-regulation may be associated with defects in differentiation of transfer cells and smaller kernels of hda101 mutants. To investigate HDA101 function during early stages of seed development, we performed genome-wide mapping of HDA101 binding sites. We observed that HDA101 mainly targets highly and intermediately expressed genes. Although loss of HDA101 can induce histone hyper-acetylation of its direct targets, this often does not involve variation in transcription. A small subset of inactive genes that must be negatively regulated during kernel development are also targeted by HDA101 and its loss leads to hyper-acetylation and increased expression of these genes. Finally, we report HDA101 interacts with members of different chromatin remodeling complexes, such as NFC103/MSI1 and SNL1/SIN3-like co-repressors. Taken together, our results reveal a complex genetic network regulated by HDA101 during seed development and provide insights into the different mechanisms of HDA101-mediated regulation of transcriptionally active and inactive genes

The Wheat NAC Transcription Factor TaNAC2L Is Regulated at the Transcriptional and Post-Translational Levels and Promotes Heat Stress Tolerance in Transgenic Arabidopsis

<div><p>Heat stress poses a serious threat to global crop production. In efforts that aim to mitigate the adverse effects of heat stress on crops, a variety of genetic tools are being used to develop plants with improved thermotolerance. The characterization of important regulators of heat stress tolerance provides essential information for this aim. In this study, we examine the wheat (<i>Triticum aestivum</i>) NAC transcription factor gene <i>TaNAC2L</i>. High temperature induced <i>TaNAC2L</i> expression in wheat and overexpression of <i>TaNAC2L</i> in <i>Arabidopsis thaliana</i> enhanced acquired heat tolerance without causing obvious alterations in phenotype compared with wild type under normal conditions. <i>TaNAC2L</i> overexpression also activated the expression of heat-related genes in the transgenic Arabidopsis plants, suggesting that TaNAC2L may improve heat tolerance by regulating the expression of stress-responsive genes. Notably, TaNAC2L is also regulated at the post-translational level and might be degraded via a proteasome-mediated pathway. Thus, this wheat transcription factor may have potential uses in enhancing thermotolerance in crops.</p></div

Expression of six stress marker genes in <i>TaNAC2L</i> transgenic Arabidopsis plants and wild type (WT) under normal and heat stress conditions.

<p>The transcript levels of <i>DREB2A</i>, <i>DREB2B</i>, <i>AtCYP18-1</i>, <i>RD17</i>, <i>HSP26</i>.<i>5</i>, <i>LEA</i>, <i>AtGolS1</i>, <i>HSP70</i>, <i>AtHsfA3</i>, and <i>RD29A</i> were determined by quantitative RT-PCR. Values represent the mean ± SD of three independent experiments and were normalized to <i>ACTIN</i>.</p

Transcript and protein levels of TaNAC2L in the <i>drip1 drip2</i> double mutant background.

<p><i>TaNAC2L</i> was highly transcribed in three independent siblings of <i>TaNAC2L</i>-overexpressed lines crossed with the <i>drip1 drip2</i> double mutant; the absence of DRIP1 and DRIP2 failed to block the degradation of the TaNAC2L protein.</p

Hypocotyl elongation of <i>TaNAC2L</i>-overexpressing transgenic Arabidopsis plants.

<p>A. Levels of the <i>TaNAC2L</i> transcript in the wild type (WT) and 20 transgenic Arabidopsis lines according to real-time quantitative PCR analyses. B. Hypocotyl elongation of WT and transgenic plants (#13) after growth for 2.5 days in the dark at 22°C. Seedling treatments included: 1) maintained at 22°C; 2) treated at 38°C for 90 min; 3) treated at 45°C for 2 h; 4) first treated at 38°C for 90 min followed by 2 h at 22°C and then 2 h at 45°C. For all treatments, seedlings were returned to 22°C for 2.5 days and then photographed. The quantitative analysis of the hypocotyl length of the wild-type and transgenic plants is presented below the photographs.</p

The frequency of conserved miRNAs present in the sequenced small RNA library

<p><b>Copyright information:</b></p><p>Taken from "Cloning and characterization of microRNAs from wheat (L.)"</p><p>http://genomebiology.com/2007/8/6/R96</p><p>Genome Biology 2007;8(6):R96-R96.</p><p>Published online 1 Jun 2007</p><p>PMCID:PMC2394755.</p><p></p