The maize opaque2 (o2) mutant has a high nutritional value but it develops a chalky endosperm that limits its practical use. Genetic selection for o2 modifiers can convert the normally chalky endosperm of the mutant into a hard, vitreous phenotype, yielding what is known as quality protein maize (QPM). Previous studies have shown that enhanced expression of 27-kDa γ-zein in QPM is essential for endosperm modification. Taking advantage of genome-wide association study analysis of a natural population, linkage mapping analysis of a recombinant inbred line population, and map-based cloning, we identified a quantitative trait locus (qγ27) affecting expression of 27-kDa γ-zein. qγ27 was mapped to the same region as the major o2 modifier (o2 modifier1) on chromosome 7 near the 27-kDa γ-zein locus. qγ27 resulted from a 15.26-kb duplication at the 27-kDa γ-zein locus, which increases the level of gene expression. This duplication occurred before maize domestication; however, the gene structure of qγ27 appears to be unstable and the DNA rearrangement frequently occurs at this locus. Because enhanced expression of 27-kDa γ-zein is critical for endosperm modification in QPM, qγ27 is expected to be under artificial selection. This discovery provides a useful molecular marker that can be used to accelerate QPM breeding.B y 2030, the world population is predicted to reach 8.5 billion people. As a consequence, food production will need to be increased by more than 50% (1). However, the rate of food production has not kept pace with explosive population growth. Enhancing the nutritional quality of staple crops is one strategy for addressing the emerging food crisis (2, 3).Maize (Zea mays) is the highest-yielding crop in the world, but it cannot be used as the sole protein source for humans and monogastric livestock because its main storage proteins, zeins, are deficient in the essential amino acids, lysine and tryptophan (4). The poor protein quality of maize can be improved by the opaque2 (o2) mutation, which increases the lysine and tryptophan levels by decreasing the synthesis of zeins and compensatorily increasing other (nonzein) seed proteins. However, unfortunately, the chalky and soft texture of o2 kernels limits utilization of this mutant (5). The creation of quality protein maize (QPM) was based on modification of o2 by accumulating quantitative trait loci (QTLs), called o2 modifiers, that lead to a hard, vitreous endosperm (5, 6). The development of QPM has greatly improved the lives of people who suffer from malnutrition in the developing countries (7).Although QPM breeding has gone on more than 50 y, neither the mechanism nor the genetic components controlling endosperm modification are well understood. Seven o2 modifiers have been located on six chromosomes (8), including one, designated o2 modifier1 in bin 7.02 near the 27-kDa γ-zein locus, which has a major effect on endosperm modification; the other six loci contribute smaller effects (8). Coincidently, the RNA transcript and protein levels of 27-kDa γ-zein accu...

Background Berberine is an isoquinoline alkaloid extracted from various Berberis species which is widely used in East Asia for a wide range of symptoms. Recently, neuroprotective effects of berberine in Alzheimer’s disease (AD) animal models are being extensively reported. So far, no clinical trial has been carried out on the neuroprotective effects of berberine. However, a review of the experimental data is needed before choosing berberine as a candidate drug for clinical experiments. We conducted a systematic review on AD rodent models to analyze the drug effects with minimal selection bias. Methods Five online literature databases were searched to find publications reporting studies of the effect of berberine treatment on animal models of AD. Up to March 2018, 15 papers were identified to describe the efficacy of berberine. Results The included 15 articles met our inclusion criteria with different quality ranging from 3 to 5. We analyzed data extracted from full texts with regard to pharmacological effects and potential anti-Alzheimer’s properties. Our analysis revealed that in multiple memory defects animal models, berberine showed significant memory-improving activities with multiple mechanisms, such as anti-inflammation, anti-oxidative stress, cholinesterase (ChE) inhibition and anti-amyloid effects. Conclusion AD is likely to be a complex disease driven by multiple factors. Yet, many therapeutic strategies based on lowering β-amyloid have failed in clinical trials. This suggest that the threapy should not base on a single cause of Alzheimer’s disease but rather a number of different pathways that lead to the disease. Overall we think that berberine can be a promising multipotent agent to combat Alzheimer’s disease.

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Light-driven micromotor has become one of the research focuses in the past decade, and its motion behavior is usually controlled by light intensity, polarization, and light wavelength. Herein, the light incident angle is utilized to control the motion behavior of silica/Au/pentacene (SiO2/Au/PEN) spherical Janus micromotor. Under tilted irradiation, a single micromotor shows positive phototactic moving behavior without the addition of external chemical fuels, which relies on the photocatalytic reactions and the self-electrophoresis mechanism. Interestingly, when the incident light is tuned to the vertical angle, the SiO2/Au/PEN micromotor stops moving. Similarly, a number of SiO2/Au/PEN micromotors exhibit the same “on–off” motion change, which is dependent on the light incident angle. More interestingly, the “on–off” motion of the SiO2/Au/PEN microparticles under vertical light irradiation results in the formation of the agglomeration with position and size precisely controlled by light. In addition, the resulting aggregation exhibits light-controlled dynamic migration behavior. The incident angle control thus opens up new opportunities for the motion control of the micromotors for diverse applications.

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A highly air-sensitive seventeen-electron half-sandwich radical, [(C6Me6)Cr(CO)3](+), which has been long sought over 40 years, was isolated and structurally characterized. EPR spectroscopy and theoretical calculations indicate that the spin density mainly resides on the chromium atom. The radical can undergo a substitution reaction with PPh3 to form a more stable cation, [(C6Me6)Cr(CO)2(PPh3)](+). This work provides a direct observation of the radical process for CO-substitution reactions found in (arene)M(CO)3 (M = Cr, Mo, or W) systems, and suggests that other stable radicals of the type [(arene)M(CO)3](+) are accessible.

Three bis(triarylamine) dications bridged with 2,2'-bithienyl group (1), biphenyl group (2) and [2,2]paracyclophane (3) have been successfully isolated. The electronic structures of 1 - 3 show bridge dependence. Magnetic studies and DFT calculations show that dications 1 - 3 possess an open-shell singlet ground state with a thermally excited triplet state. Dication 3 has rather small singlet-triplet energy gap and could basically be regarded as a nearly pure diradical. Diradical dications 1 - 3 represent rare examples of diradicaloids with intramolecular long-range π-conjugation or π-π coupling interaction.

An air-stable N,N′-dihydroporphycene, the twoelectron reduced form of porphycene, possessing two quinoxaline moieties fused at meso positions, was prepared and characterized. Nuclear magnetic resonance (NMR) and ultraviolet−visible light (UV-vis) spectroscopic studies and single-crystal X-ray diffraction analyses support its formulation as a nonaromatic species. Upon treatment with tetrabutylammonium fluoride (TBAF) in chloroform, a color change is produced that is consistent with deprotonation. Selective detection of this anion is readily achieved.Letter pubs.acs.org/OrgLett