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In this study, a methylation-sensitive amplification polymorphism analysis system was used to analyze DNA methylation level in three cotton accessions. Two disease-sensitive near-isogenic lines, PD94042 and IL41, and one disease-resistant Gossypium mustelinum accession were exposed to Verticillium wilt, to investigate molecular disease resistance mechanisms in cotton. We observed multiple different DNA methylation types across the three accessions following Verticillium wilt exposure. These included hypomethylation, hypermethylation, and other patterns. In general, the global DNA methylation level was significantly increased in the disease-resistant accession G. mustelinum following disease exposure. In contrast, there was no significant difference in the disease-sensitive accession PD94042, and a significant decrease was observed in IL41. Our results suggest that disease-resistant cotton might employ a mechanism to increase methylation level in response to disease stress. The differing methylation patterns, together with the increase in global DNA methylation level, might play important roles in tolerance to Verticillium wilt in cotton. Through cloning and analysis of differently methylated DNA sequences, we were also able to identify several genes that may contribute to disease resistance in cotton. Our results revealed the effect of DNA methylation on cotton disease resistance, and also identified genes that played important roles, which may shed light on the future cotton disease-resistant molecular breeding.

Ultrathin high-quality Bi2Te3 and Bi2Se3 topological insulator nanoplates are prepared on n-type and p-type silicon (111) substrates via vapor phase deposition method forming topological insulator–silicon heterostructures. The quantitative results obtained by Kelvin probe force microscopy indicate that the work function and Fermi level of both Bi2Te3 and Bi2Se3 nanoplates depend on the substrates, which are ascribed to the charge exchange that exists at the interface between nanoplates and silicon substrates with different doping. Our results provide an effective strategy to tune electronic properties of TI nanostructures through topological insulator–silicon heterostructures.

RNA editing can alter individual nucleotides in primary transcripts, which can cause the amino acids encoded by edited RNA to deviate from the ones predicted from the DNA template. We investigated RNA editing sites of protein-coding genes from the chloroplast genome of cotton. Fifty-four editing sites were identified in 27 transcripts, which is the highest editing frequency found until now in angiosperms. All these editing sites were C-to-U conversion, biased toward ndh genes and U_A context. Examining published editotypes in various angiosperms, we found that RNA editing mostly converts amino acid from hydrophilic to hydrophobic and restores evolutionary conserved amino acids. Using bioinformatics to analyze the effect of editing events on protein secondary and three-dimensional structures, we found that 21 editing sites can affect protein secondary structures and seven editing sites can alter three-dimensional protein structures. These results imply that 24 editing sites in cotton chloroplast transcripts may play an important role in their protein structures and functions.

A total of 624-day-old Arbor Acres male broilers were used to investigate the relative bioavailabilities of supplemental organic manganese sources for broilers fed high calcium diets. The broilers were randomly allotted to six replicate cages (eight chicks per cage) for each of 13 treatments in a completely randomized design involving a 4×3 factorial arrangement of treatments (four sources of Mn×three levels of added Mn, plus the control with no added Mn). Dietary treatments included the high calcium basal diet (the Control, containing 18.5 g Ca/kg and 20 mg Mn/kg) and the basal diet supplemented with 60, 120, or 180 mg Mn/kg as Mn sulphate (MnSO4·H2O) or Mn methionine E (Mn Met E) with weak chelation strength [formation quotient (Qf) = 3.2, containing 82.7 g Mn/kg], Mn amino acid B (Mn AA B) with moderate chelation strength (Qf = 45.3, containing 64.8 g Mn/kg), or Mn amino acid C (Mn AA C) with strong chelation strength (Qf = 115.4, containing 78.6 g Mn/kg). Heart manganese-containing superoxide dismutase (MnSOD) mRNA level and heart Mn concentration increased as supplemental dietary Mn increased (P

Most recently 't Hooft has postulated (G. 't Hooft, Class. Quantum Grav.16, 3263 (1999)) that quantum states at the "atomic scale" can be understood as equivalence classes of primordial states governed by a dissipative deterministic theory underlying quantum theory at the "Planck scale". Defining invariant subspaces clearly for primordial states according to a given evolution, we mathematically reformulate 't Hooft's theory as a quotient space construction with the time-reversible evolution operator induced naturally. With this observation and some analysis, 't Hooft's theory is generalized beyond his case where the evolution at the "Planck scale" is a power of a one-time-step evolution or the time is discrete.

Based on the Born-Oppenhemer approximation, the concept of adiabatic quantum entanglement is introduced to account for quantum decoherence of a quantum system due to its interaction with a large system of one or a few degrees of freedom. In the adiabatic limit, it is shown that the wave function of the total system formed by the quantum system plus the large system can be factorized as an entangled state with correlation between adiabatic quantum states and quasi-classical motion configurations of the large system. In association with a novel viewpoint about quantum measurement, which has been directly verified by most recent experiments [e.g., S. Durr et al., Nature 33, 359 (1998)], it is shown that the adiabatic entanglement is indeed responsible for the quantum decoherence and thus can be regarded as a “clean” quantum measurement when the large system behaves as a classical object. By taking the large system respectively to be a macroscopically distinguishable spatial variable, a high spin system and a harmonic oscillator with a coherent initial state, three illustrations are presented with their explicit solutions in this paper.

Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is an adult-onset myopathy characterized by distal lower limb weakness, calf hypertrophy and progressive decline in ambulation. The disease is caused by mutations in Tcap, a z-disc protein of skeletal muscle, although the precise mechanisms resulting in clinical symptoms are unknown. To provide a model for preclinical trials and for mechanistic studies, we generated knockout (KO) mice carrying a null mutation in the Tcap gene. Here we present the first report of a Tcap KO mouse model for LGMD2G and the results of an investigation into the effects of Tcap deficiency on skeletal muscle function in 4- and 12-month-old mice. Muscle histology of Tcap-null mice revealed abnormal myofiber size variation with central nucleation, similar to findings in the muscles of LGMD2G patients. An analysis of a Tcap binding protein, myostatin, showed that deletion of Tcap was accompanied by increased protein levels of myostatin. Our Tcap-null mice exhibited a decline in the ability to maintain balance on a rotating rod, relative to wild-type controls. No differences were detected in force or fatigue assays of isolated extensor digitorum longus (EDL) and soleus (SOL) muscles. Finally, a mechanical investigation of EDL and SOL indicated an increase in muscle stiffness in KO animals. We are the first to establish a viable KO mouse model of Tcap deficiency and our model mice demonstrate a dystrophic phenotype comparable to humans with LGMD2G.

Ethnopharmacological relevance Acanthopanax senticosus (Rupr.et Maxim.) Harms, classified into the family of Araliaceae, is used in a variety of diseases in traditional Chinese system of medicine including hypertension, ischemic heart disease and hepatitis. Materials and methods Different doses (75 mg/kg, 150 mg/kg and 300 mg/kg) of aqueous extracts of Acanthopanax senticosus Harms were evaluated for the antioxidant activity against oxidative stress in mice induced by tert-butyl hydroperoxide (t-BHP) through observating histopathology of the liver and detecting antioxidant enzyme activity, concentration of antioxidant, and related gene and protein expression. Results Acanthopanax senticosus Harms aqueous extracts (ASE) attenuated the morphological injury of liver induced by t-BHP and increased the activity of antioxidant enzymes and the ratio of GSH/GSSG in serum and liver homogenates. Medium and high doses of ASE also elevated the gene expression of NF-E2-related factor-2 (Nrf2), but not CuZnSOD, MnSOD, catalase (CAT), glutathione peroxidase (GPx) and GCLC. Protein expression results showed that Nrf2 and the antioxidant enzymes were all increased significantly by medium and high doses of ASE. Conclusion The present results indicated that ASE protect against oxidative stress which may be generated via the induction of Nrf2 and related antioxidant enzymes.

Electron-nuclear double resonance (ENDOR) spectroscopy has been applied to Cu(II)-doped l -histidine deuterochloride monodeuterohydrate single crystals at 4.2 K. Detailed analysis of the ENDOR spectra allowed the determination of the principal values and direction cosines of the hyperfine coupling, and nuclear quadropole coupling tensors for two 14 N and the 35 Cl nuclei. Also, we evaluated the asymmetry parameters η for those nuclei. The assignment of the tensors to the molecular frame enabled us to identify one of the nitrogen nuclei, N1, as belonging to the amino group, and N3 as one of the imidazole nitrogen atoms. The analysis of the data also shows that the Cu(II) site has octahedral symmetry and it possesses C 2 symmetry along the C(I)Cu(II)Cl(II) axis. Theoretical calculations of the two 14 N and the 35 Cl quadrupole coupling constants, and the charge distributions in the bonds, were performed using the Townes-Dailey approximation. In addition we calculated theoretical values for the components of the g tensor using the method introduced by Lin (J. Mag. Reson., 68 (1986) 146) in which the complete energy matrix including, the ligand field, electron—electron repulsion, and spin—orbit coupling are simultaneously diagonalized. To evaluate the ligand-field matrix elements, the angular overlap model (AOM) was used. The theoretical calculations are in excellent agreement with the experimental values.

In this paper, three criteria which judge the origin of the Lienard system to be a center are given.