Myostatin inhibits differentiation of bovine preadipocyte

We investigated the effect of myostatin on the differentiation of bovine preadipocyte. Stromal-vascular cells containing preadipocytes were prepared from perirenal adipose tissue of approximately 30-month-old Japanese Black steers. After confluence, the differentiation was induced by 1-methyl-3-isobutyl-xanthine, dexamethasone, insulin, and troglitasone for 2 days, and then subsequently cultured for 6 days. The cells were treated with myostatin during the induction of differentiation (the early phase of differentiation) or throughout the differentiation period. We measured the terminal differentiation markers such as glycerol-3-phosphate dehydrogenase activity, lipid accumulation, and the expression of adipocyte fatty acid-binding protein mRNA at the end of cultures. The treatment with myostatin throughout the differentiation period severely suppressed the induction of all differentiation markers. The treatment with myostatin in the early phase of differentiation also suppressed the induction of terminal differentiation markers but three-fold higher dose of myostatin was required for the suppression compared with its treatment throughout the differentiation period. Myostatin treatment reduced the expression of peroxisome proliferator-activated receptor (PPAR) gamma mRNA and interfered with the induction of CCAAT/enhancer binding protein (C/EBP) alpha mRNA. We also observed that follistatin stimulates preadipocyte differentiation in the presence of myostatin. These results suggest that myostatin inhibits bovine preadiopocyte differentiation through suppressing PPARgamma and C/EBPalpha mRNA expressions and that follistatin counteracts the suppressive effect of myostatin.     

Vanillin production from native softwood lignin in the presence of tetrabutylammonium ion

Vanillin is one of the industrially important compounds that can be produced from lignin. This study presents production of vanillin and vanillic acid (oxidized form of vanillin) through aerobic oxidation of Japanese cedar (Cryptomeria japonica) at 120 °C for 72 h in aqueous alkali solutions with several Bu₄N⁺ and OH^? concentrations (1.25, 2.50, and 3.75 mol/L), where Bu₄N⁺ is an enhancer of the vanillin formation reported in our previous study. The concentrations of Bu₄N⁺ and OH^? were adjusted by the additions of Bu₄NCl and solid NaOH into the base medium Bu₄NOH·30H₂O, which forms 1.25 mol/L aqueous solution of Bu₄NOH at the elevated temperature. Vanillin and vanillic acid were produced with the maximum yields of 21.0 and 1.7 wt% (lignin-base), respectively, at the 1.25 mol/L Bu₄N⁺ and 3.75 mol/L OH^? concentrations. This vanillin yield is close to that obtained by the alkaline nitrobenzene oxidation (26.5 wt%), indicating significantly high selectivity of our lignin degradation with Bu₄N⁺ toward vanillin formation. We also proposed a novel Bu₄NOH·30H₂O-free reaction medium, where Bu₄NOH·30H₂O as the base medium were substituted with an aqueous solution of Bu₄NCl and NaOH to avoid using expensive Bu₄NOH·30H₂O. The treatment of the Japanese cedar with this alternative medium exhibited the moderately decreased vanillin yield of 14.6 wt%, which is, however, much higher than the vanillin yield obtained with a simple 1.25 mol/L NaOH solution.     

QTL mapping of fruit nutritional and flavor components in tomato (<Emphasis Type="Italic">Solanum lycopersicum</Emphasis>) using genome-wide SSR markers and recombinant inbred lines (RILs) from an intra-specific cross

Fruit nutritional and flavor components are important targets for breeding new cultivars of tomato (Solanum lycopersicum L.). We developed 108 recombinant inbred lines (the K39 RILs) in the F₆ generation from a cross between two phenotypically different breeding lines, K03 and K09. A linkage map was constructed using 172 genome-wide simple sequence repeat markers, 3 single-nucleotide polymorphism markers, and 2 phenotypic markers. The K39 RIL map consists of 12 linkage groups (LGs) and covers a genetic distance of 1089 cM. We measured the fruit soluble solids content (SSC), titratable acidity (TA), glutamic acid content (GLU), and lycopene content (LYC) of each line in four generations (F₆, F₈, F₁₀, F₁₁), β-carotene content (CAR) in two generations, and pH in one generation. By composite interval mapping that considered yearly variations in components as non-genetic effects, we detected three quantitative trait loci (QTLs) for SSC, four for TA, two for CAR, and one each for GLU, LYC, and pH. Among them, we found two QTLs for TA in LGs 6 and 11, those for GLU and LYC were candidates for novel QTLs. QTLs detected in this study were clustered in five LGs, but we observed no apparent trade-off relationships among the QTLs in each LG. Being derived from an intra-specific cross of tomato breeding materials, these QTLs can be used in practical breeding for improving fruit quality with low risk of linkage drag.     

Incorporation of fallow weed increases phosphorus availability in a farmer’s organic rice fields on allophanic Andosol in eastern Japan

ABSTRACT

We investigated the amount of soil phosphorus (P) in a farmer’s paddy fields under organic farming (OF) for various periods from 0 to 22 years as well as other farmers’ fields under conventional farming. All the fields are located in allophanic Andosol with long history of P fertilizer application, and some of them have been converted to OF across years. After conversion to OF, P was supplied only with winter fallow weeds mainly Foxtail (Alopecurus aequalis), rice residues (rice bran and straw), and guano. We determined total-P (Tot-P) and plant-available P (Av-P), which consists of Truog-P (Tru-P) and Bray-2-P under reducing condition with ascorbic acid (Asc-P), in soils of each field. For both Av-Ps, the ratio to Tot-P increased across years under OF following quadratic functions with both linear and quadratic terms being statistically significant. The ratios showed little changes for the initial 15 (Tru-P) or 10 (Asc-P) years and increased rapidly thereafter. These temporal changes in Av-P were consistent with the rapid increase of the amount of P accumulated in the winter fallow weeds and incorporated in the fields after beginning of OF. These results led us to the hypothesis that the incorporation of winter weeds has contributed to the increase of Av-P in the organic fields across years. We tested this hypothesis by investigating temporal changes of Av-P after suspending the weed incorporation for 2 consecutive years in plots of the organic fields. Both Av-Ps were significantly greater in plots with continued weed incorporation (CWI) than those in plots with its suspension. We further found that the increase of Asc-P in plots with CWI was 4.9-fold the input of total P in the incorporated weeds. This suggests that the incorporation of winter fallow weeds enhanced soil-P availability beyond the supply of P accumulated in the weeds.     

Estimation of rice protein content before harvest using ground-based hyperspectral imaging and region of interest analysis

Protein content, which represents rice taste quality, must be estimated in order to create a harvesting plan as well as next year’s basal dressing fertilizer application plan. Ground-based hyperspectral imaging with high resolution (1 × 1 mm per pixel) was used for estimating the protein content of brown rice before harvest. This paper compares the estimation accuracy of rice protein content estimation models generated from the mean reflectances of five regions of interest (ROIs): the overall target area, dark area (less illuminated parts of the rice plants), canopy area (leaves, yellow leaves, and ears), leaf area, and ear and yellow leaf area. The size of the target sampling area was 0.85 × 0.85 m. An R + G + B histogram and a GNDVI–NDVI image were used to separate the target area into the individual ROIs. The values of the coefficient of determination R ² and the root mean square error of prediction (RMSE) were similar for each model: R ² ranged from 0.83 to 0.86 and RMSE ranged from 0.27 to 0.30% for all models except for the dark area model, where R ² = 0.76 and RMSE = 0.35%. There were no significant differences in the magnitude of the estimation error among all models. This result indicates that it is not necessary to obtain an image with a ground resolution that is greater than 0.85 × 0.85 m per pixel to estimate rice protein content before harvest. This result should provide useful information when deciding the altitude of platforms for imaging rice fields.     

Influence of weed management measures on glyphosate resistance and endophyte infection in naturalized Italian ryegrass (Lolium multiflorum)

Recently, glyphosate‐resistant Italian ryegrass (Lolium multiflorum Lam.) was found on rice paddy levees in a western region of Shizuoka Prefecture, Japan. Naturalized populations of Italian ryegrass are frequently infected with fungal Epichloë endophytes. Endophytes often confer benefits to their host grasses. This study investigated the influence of five weed management treatments on glyphosate resistance and endophyte infection in Italian ryegrass that was growing on paddy levees where glyphosate‐resistant individuals were dominant. The weed management treatments were: (i) mowing once before the grass flowered; (ii) mowing once during flowering; (iii) mowing twice during flowering; (iv) glyphosate application before flowering; and (v) no treatment. The seeds were collected from the treatment plots in 2013 and 2014. The seeds were examined for endophyte infection and the seedlings that had been grown from the seeds were tested for the frequency of glyphosate resistance. The seedlings that had been derived from the glyphosate treatment showed higher frequencies of glyphosate resistance than those seedlings that had been derived from all the other treatments. Endophytes were found in all populations of the seeds from the paddy levees, with higher infection rates in the seeds that had been derived from the glyphosate treatment and the twice‐mowed treatment. There was a significant relationship between the endophyte infection frequency in the seeds and glyphosate resistance in the seedlings that had been grown from the same populations. The results indicate that where glyphosate herbicides are frequently used, selection for glyphosate‐resistant Italian ryegrass occurs, and along with this, the frequency of endophyte infection also increases.     

Rapid and low-cost diagnosis of <Emphasis Type="Italic">Japanese yam mosaic virus</Emphasis> infection in Chinese yam (<Emphasis Type="Italic">Dioscorea polystachya</Emphasis>) leaves by a print-capture RT-PCR

A rapid diagnostic method for Japanese yam mosaic virus (JYMV) infection in Chinese yam (Dioscorea polystachya) by a print-capture RT-PCR was developed. The cut surface of a rolled leaf of a JYMV-infected Chinese yam was stamped onto a nitrocellulose membrane. The clipped membrane was boiled in eluting solution to elute the RNA for use as the template in RT-nested PCR. Although JYMV RNA was detectable in most infected plants in the first PCR of the print-capture RT-PCR, it was detected from all samples in the nested PCR. The tissue-printed membranes could be preserved for at least 3 months at 4?°C for JYMV detection.     

Reduction of dietary lysine increases free glutamate content in chicken meat and improves its taste

Taste is a crucial factor of meat quality, and amino acids are important taste‐active components in meat. Here, the effects of dietary lysine (Lys) content on taste‐active components in meat, especially free glutamate (Glu), were investigated. Twenty‐eight‐day‐old broilers (Gallus gallus) were fed diets with graded Lys content of 90% or 100% of the recommended Lys requirement, (according to the National Research Council, 1994 ) for 10 days. Free amino acid content in meat and sensory scores of meat soup were estimated. Free Glu content, the main taste‐active component of meat, was significantly increased by a reduction of dietary Lys. Compared with the Lys 100% group (control), free Glu concentrations of meat were increased by 35.7% in the Lys 90% group (P < 0.05). In addition, free glycine, valine, isoleucine, leucine, histidine and threonine concentrations of meat were significantly increased in the Lys 90% group (P < 0.05). Sensory evaluation of meat soup made from the Lys 100% and 90% groups indicated different meat tastes. Sensory scores of taste intensity, umami and kokumi tastes were significantly higher in the Lys 90% group. These results suggest that a reduction of dietary lysine increased free glutamate content in meat and improved its taste.