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The ability to fight or flee from a threat relies on an acute adrenergic surge that augments cardiac output, which is dependent on increased cardiac contractility and heart rate. This cardiac response depends on [beta]-adrenergic-initiated reversal of the small RGK G protein Rad-mediated inhibition of voltage-gated calcium channels ([Ca.sub.v]) acting through the [Ca.sub.v][beta] subunit. Here, we investigate how Rad couples phosphorylation to augmented [Ca.sup.2+] influx and increased cardiac contraction. We show that reversal required phosphorylation of [Ser.sup.272] and [Ser.sup.300] within Rad's polybasic, hydrophobic C- terminal domain (CTD). Phosphorylation of [Ser.sup.25] and [Ser.sup.38] in Rad's N-terminal domain (NTD) alone was ineffective. Phosphorylation of [Ser.sup.272] and [Ser.sup.300] or the addition of 4 Asp residues to the CTD reduced Rad's association with the negatively charged, cytoplasmic plasmalemmal surface and with [Ca.sub.v][beta], even in the absence of [Ca.sub.v][alpha], measured here by FRET. Addition of a posttranslationally prenylated CAAX motif to Rad's C-terminus, which constitutively tethers Rad to the membrane, prevented the physiological and biochemical effects of both phosphorylation and Asp substitution. Thus, dissociation of Rad from the sarcolemma, and consequently from [Ca.sub.v][beta], is sufficient for sympathetic upregulation of [Ca.sup.2+] currents., Introduction Calcium influx through voltage-gated L-type [Ca.sup.2+] channels ([Ca.sub.v]1.2) is an essential link in the chain of signals that trigger the contraction of every heartbeat. Norepinephrine released from sympathetic neurons [...]

The g-C3N4/Ag/Bi2O2CO3 nanosheets were synthesized using a mixture of precursors containing melamine and nitrates of silver and bismuth through a simple one-pot synthesis strategy. In the presence of ammonium nitrate, g-C3N4/Ag/Bi2O2CO3 composite catalysts with different silver mass ratios were prepared, and the photodegradation performance of the composite samples was evaluated by photodegradation of tetracycline hydrochloride (TC) under simulated solar light irradiation. The synthesized composites were characterized by XPD, XPS, FT-IR, TEM, UV–vis DRS and PL. It was found that the g-C3N4/Ag/Bi2O2CO3 catalyst with Ag mass ratio of 4% exhibited the highest catalytic activity, and the degradation effect was more than 9 times that of pure C3N4 and nearly 5 times that of g-C3N4/Bi2O2CO3.In addition, cyclic experiments showed that g-C3N4/Ag/Bi2O2CO3 composites had certain stability. The photocatalytic performance of the g-C3N4/Ag/Bi2O2CO3 composites was attributable to the heterogeneous junction of Bi2O2CO3 and g-C3N4 and the surface plasmon resonance effect (SPR) of Ag nanoparticles. The energy levels of Bi2O2CO3 and g-C3N4 were properly matched to form a heterojunction, which promoted the separation and transfer of photogenerated electrons and holes, thereby improving the photocatalytic performance. The Ag surface plasmon resonance (SPR) effect not only accelerated the separation and transmission of electron–hole pairs, but also enhanced the absorption of visible light. Finally, based on the above basis, a possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Powdery mildew is a severe wheat disease that causes substantial yield losses in wheat production worldwide. The Chinese wheat landrace Changanhongmai (CAHM) exhibits high resistance to the physiological race E09 of powdery mildew. In this study, we characterized the powdery mildew resistance gene in CAHM, and developed molecular markers for wheat marker-assisted selection. To investigate the genetic characteristics of this resistant gene, we developed F1 plants, F2 generation population, and F2:3 families by crossing CAHM with SY225 (Shaanyou '225' as susceptible male parent). Genetic analysis demonstrated that all F1 plants were resistant to the disease, while the ratio of resistant to susceptible plants was 3: 1 in both the F2 population and F2:3 families, indicating that CAHM is inherited in a manner of a single dominant powdery mildew resistance gene, which was tentatively designated as PmCAHM. By using bulk segregation analysis, we constructed a genetic map encompassing Xgwm273, Xwmc626, Xgwm11, Xgwm18, Xgdm28, Xgpw7812, Xgpw5195, Xwmc694, and PmCAHM. Among these markers, Xgpw7812 and Xgpw5195 are flanking markers that are tightly linked to PmCAHM at a genetic distance of 2.5 cM and 8.4 cM, respectively. Furthermore, nullisomic-tetrasomic analysis revealed that PmCAHM is located on chromosome 1B. These results indicate that PmCAHM differs from the internationally recognized powdery mildew resistance genes in both location and source. In addition, a new germplasm/line NW1748 with stronger powdery mildew resistance and large grains was developed from the cross and backcross populations of Fengyou1718 (FY1718)/CAHM/5/FY 1718. Therefore, PmCAHM can serve as a novel powdery mildew resistance source for breeding of wheat by using NW1748 as the donor in the future. [ABSTRACT FROM AUTHOR]

[Ca.sup.2+] channel [beta]-subunit interactions with pore-forming [alpha]-subunits are long-thought to be obligatory for channel trafficking to the cell surface and for tuning of basal biophysical properties in many tissues. Unexpectedly, we demonstrate that transgenic expression of mutant [[alpha].sub.1C] subunits lacking capacity to bind [Ca.sub.V][beta] can traffic to the sarcolemma in adult cardiomyocytes in vivo and sustain normal excitation-contraction coupling. However, these [beta]-less [Ca.sup.2+] channels cannot be stimulated by [beta]-adrenergic pathway agonists, and thus adrenergic augmentation of contractility is markedly impaired in isolated cardiomyocytes and in hearts. Similarly, viral-mediated expression of a [beta]-subunit-sequestering peptide sharply curtailed [beta]-adrenergic stimulation of WT [Ca.sup.2+] channels, identifying an approach to specifically modulate [beta]-adrenergic regulation of cardiac contractility. Our data demonstrate that [beta] subunits are required for [beta]-adrenergic regulation of [Ca.sub.V]1.2 channels and positive inotropy in the heart, but are dispensable for [Ca.sub.V]1.2 trafficking to the adult cardiomyocyte cell surface, and for basal function and excitation-contraction coupling., Introduction In heart cells, [Ca.sup.2+] influx via [Ca.sub.V]1.2 channels mediates excitation-contraction (E-C) coupling, controls action potential duration, and regulates gene expression. [Ca.sub.V]1.2 channels are multi-subunit proteins composed minimally of a [...]

Novel Ag/Fe2O3/BiOI Z-scheme heterostructures are first fabricated through a facile hydrothermal method. The composition and properties of as-synthesized Ag/Fe2O3/BiOI nanocomposites are characterized by powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, UV-Vis diffuse reflectance spectra, etc. The Ag/Fe2O3/BiOI systems exhibit remarkable degradation performance for tetracycline (TC). In particular, the composite (Ag/Fe2O3/BiOI-2) shows the highest efficiency when the contents of Ag and α-Fe2O3 are 2 wt% and 15%, respectively. The effects of operating parameters, including the solution pH, H2O2 concentration, TC concentration, and catalyst concentration, on the degradation efficiency are investigated. The photo-Fenton mechanism is studied, and the results indicated that •O2− is the main active specie for TC degradation. The enhanced performance of Ag/Fe2O3/BiOI heterostructures may be ascribed to the synergic effect between photocatalysis and the Fenton reaction. The formation of Ag/Fe2O3/BiOI heterojunction is beneficial to the transfer and separation of charge carriers. The photo-generated electrons accelerate the Fe2+/Fe3+ cycle and create the reductive reaction of H2O2. This research reveals that the Ag/Fe2O3/BiOI composite possesses great potential in wastewater treatment. [ABSTRACT FROM AUTHOR]

α-Synuclein (α-Syn) is a major biomarker of Parkinson's disease (PD). Concentration detection of α-Syn in cerebrospinal fluid and plasma of patients are used as a clue for early PD detection. Herein, we propose a thin-film transistor (TFT) biosensor based on an indium gallium zinc oxide (IGZO) thin film fabricated by the sol-gel method. The IGZO TFT biosensor is used for the early detection of PD after surface functionalization for α-Syn. The surface functionalization worked on the surface of the extended gate indium tin oxide sensing platform instead of the channel layer of TFT. Depending on concentrations of α-Syn in human cerebrospinal fluid and plasma, we diluted six different concentrations of α-Syn for detection, ranging from 1 pg ml−1 to 100 ng ml−1. The result shows that the biosensor exhibits high sensitivity and selectivity for α-Syn, a reliable sensing performance with a sensitivity of 189.9 mV dec−1, and a coefficient of determination R2 of 99.7% between 10 pg ml−1 and 100 ng ml−1. [ABSTRACT FROM AUTHOR]