Regenerating plants from in vitro culture of Erigeron breviscapus leaves

A protocol to efficiently achieve plant regeneration from leaf explants of Erigeron breviscapus (Compositae) has been developed. Leaf explants produced calli on Murashige and Skoog’s (1962) basal medium (MS) supplemented with 6-benzylaminopurine (BAP) (0.4 mM) and 2,4-dichlorophenoxyacetic acid (2,4-D) (0.4-22.6 mM) under a 16-h photoperiod. Direct adventitious shoots were induced from leaf explants on MS medium containing BAP (22.2 mM) and IAA (5.7 mM) under the light treatment. The effect of the dark incubation on shoot regeneration from leaves indicated that 15 days of darkness permitted a higher regeneration frequency (82.6%) on the medium supplemented with BAP (4.4 mM) and indole-3- acetic acid (IAA) (0.6 mM). Regenerated shoots were rooted on MS medium with or without naphthaleneacetic acid (NAA). Plantlets were cultivatable in the greenhouse after acclimatization

Antioxidant treatment enhances human mesenchymal stem cell anti-stress ability and therapeutic efficacy in an acute liver failure model

published_or_final_versio

SUMO-2 promotes mRNA translation by enhancing interaction between eIF4E and eIF4G

Small ubiquitin-like modifier (SUMO) proteins regulate many important eukaryotic cellular processes through reversible covalent conjugation to target proteins. In addition to its many well-known biological consequences, like subcellular translocation of protein, subnuclear structure formation, and modulation of transcriptional activity, we show here that SUMO-2 also plays a role in mRNA translation. SUMO-2 promoted formation of the active eukaryotic initiation factor 4F (eIF4F) complex by enhancing interaction between Eukaryotic Initiation Factor 4E (eIF4E) and Eukaryotic Initiation Factor 4G (eIF4G), and induced translation of a subset of proteins, such as cyclinD1 and c-myc, which essential for cell proliferation and apoptosis. As expected, overexpression of SUMO-2 can partially cancel out the disrupting effect of 4EGI-1, a small molecule inhibitor of eIF4E/eIF4G interaction, on formation of the eIF4F complex, translation of the cap-dependent protein, cell proliferation and apoptosis. On the other hand, SUMO-2 knockdown via shRNA partially impaired cap-dependent translation and cell proliferation and promoted apoptosis. These results collectively suggest that SUMO-2 conjugation plays a crucial regulatory role in protein synthesis. Thus, this report might contribute to the basic understanding of mammalian protein translation and sheds some new light on the role of SUMO in this process. © 2014 Chen et al

Controllable Synthesis of Single-Crystalline CdO and Cd(OH)2Nanowires by a Simple Hydrothermal Approach

Single-crystalline Cd(OH)2 or CdO nanowires can be selectively synthesized at 150 °C by a simple hydrothermal method using aqueous Cd(NO3)2 as precursor. The method is biosafe, and compared to the conventional oil-water surfactant approach, more environmental-benign. As revealed by the XRD results, CdO or Cd(OH)2 nanowires can be generated in high purity by varying the time of synthesis. The results of FESEM and HRTEM analysis show that the CdO nanowires are formed in bundles. Over the CdO-nanowire bundles, photoluminescence at ~517 nm attributable to near band-edge emission of CdO was recorded. Based on the experimental results, a possible growth mechanism of the products is proposed

A diagnosis of the plasma waves responsible for the explosive energy release of substorm onset

During geomagnetic substorms, stored magnetic and plasma thermal energies are explosively converted into plasma kinetic energy. This rapid reconfiguration of Earth’s nightside magnetosphere is manifest in the ionosphere as an auroral display that fills the sky. Progress in understanding of how substorms are initiated is hindered by a lack of quantitative analysis of the single consistent feature of onset; the rapid brightening and structuring of the most equatorward arc in the ionosphere. Here, we exploit state-of-the-art auroral measurements to construct an observational dispersion relation of waves during substorm onset. Further, we use kinetic theory of high-beta plasma to demonstrate that the shear Alfven wave dispersion relation bears remarkable similarity to the auroral dispersion relation. In contrast to prevailing theories of substorm initiation, we demonstrate that auroral beads seen during the majority of substorm onsets are likely the signature of kinetic Alfven waves driven unstable in the high-beta magnetotail