Morpho-physiological and molecular mechanisms of phenotypic root plasticity for rice adaptation to water stress conditions

Different types of water stress severely affect crop production, and the plant root system plays a critical role in stress avoidance. In the case of rice, a cereal crop cultivated under the widest range of soil hydrologic conditions, from irrigated anaerobic conditions to rainfed conditions, phenotypic root plasticity is of particular relevance. Recently, important plastic root traits under different water stress conditions, and their physiological and molecular mechanisms have been gradually understood. In this review, we summarize these plastic root traits and their contributions to dry matter production through enhancement of water uptake under different water stress conditions. We also discuss the physiological and molecular mechanisms regulating the phenotypic plasticity of root systems.     

Correction: QTL mapping under salt stress in rice using a Kalarata–Azucena population

Euphytica - The color of flour and its end-use products is an important quality trait of wheat. Understanding the genetic basis of this trait is essential for improving wheat quality. In this...     

Role of adaptor TRIF in the MyD88-independent toll-like receptor signaling pathway

Stimulation of Toll-like receptors (TLRs) triggers activation of a common MyD88-dependent signaling pathway as well as a MyD88-independent pathway that is unique to TLR3 and TLR4 signaling pathways leading to interferon (IFN)-beta production. Here we disrupted the gene encoding a Toll/IL-1 receptor (TIR) domain-containing adaptor, TRIF. TRIF-deficient mice were defective in both TLR3- and TLR4-mediated expression of IFN-beta and activation of IRF-3. Furthermore, inflammatory cytokine production in response to the TLR4 ligand, but not to other TLR ligands, was severely impaired in TRIF-deficient macrophages. Mice deficient in both MyD88 and TRIF showed complete loss of nuclear factor kappa B activation in response to TLR4 stimulation. These findings demonstrate that TRIF is essential for TLR3- and TLR4-mediated signaling pathways facilitating mammalian antiviral host defense.     

Lack of exposed ice inside lunar south pole Shackleton Crater

The inside of Shackleton Crater at the lunar south pole is permanently shadowed; it has been inferred to hold water-ice deposits. The Terrain Camera (TC), a 10-meter-resolution stereo camera onboard the Selenological and Engineering Explorer (SELENE) spacecraft, succeeded in imaging the inside of the crater, which was faintly lit by sunlight scattered from the upper inner wall near the rim. The estimated temperature of the crater floor, based on the crater shape model derived from the TC data, is less than approximately 90 kelvin, cold enough to hold water-ice. However, at the TC's spatial resolution, the derived albedo indicates that exposed relatively pure water-ice deposits are not on the crater floor. Water-ice may be disseminated and mixed with soil over a small percentage of the area or may not exist at all.     

Formation of a one-dimensional array of oxygen in a microporous metal-organic solid

We report the direct observation of dioxygen molecules physisorbed in the nanochannels of a microporous copper coordination polymer by the MEM (maximum entropy method)/Rietveld method, using in situ high-resolution synchrotron x-ray powder diffraction measurements. The obtained MEM electron density revealed that van der Waals dimers of physisorbed O2 locate in the middle of nanochannels and form a one-dimensional ladder structure aligned to the host channel structure. The observed O-O stretching Raman band and magnetic susceptibilities are characteristic of the confined O2 molecules in one-dimensional nanochannels of CPL-1 (coordination polymer 1 with pillared layer structure).     

A membrane-anchored protein kinase involved in Brassica self-incompatibility signaling

Self-incompatibility (SI) response in Brassica is initiated by haplotype-specific interactions between the pollen-borne ligand S locus protein 11/SCR and its stigmatic S receptor kinase, SRK. This binding induces autophosphorylation of SRK, which is then thought to trigger a signaling cascade that leads to self-pollen rejection. A recessive mutation of the modifier (m) gene eliminates the SI response in stigma. Positional cloning of M has revealed that it encodes a membrane-anchored cytoplasmic serine/threonine protein kinase, designated M locus protein kinase (MLPK). Transient expression of MLPK restores the ability of mm papilla cells to reject self-pollen, suggesting that MLPK is a positive mediator of Brassica SI signaling.     

Gigantic photoresponse in 1/4-filled-band organic salt (EDO-TTF)2PF6

We report that the organic salt (EDO-TTF)2PF6 with 3/4-filled-band (1/4-filled in terms of holes), which forms an organic metal with strong electron and lattice correlation, shows a highly sensitive response to photoexcitation. An ultrafast, photoinduced phase transition from the insulator phase to the metal phase can be induced with very weak excitation intensity at near room temperature. This response makes the material attractive for applications in switching devices with room-temperature operation. The observed photo-induced spectroscopic change shows that this photoinduced phase transition process is caused by the cooperative melting of charge ordering assisted by coherent phonon generation.