Pea extracellular Cu/Zn-superoxide dismutase responsive to signal molecules from a fungal pathogen

We previously reported that the release of O₂ ⁻ from isolated pea cell walls was enhanced by a 70-kDa glycoprotein elicitor but was suppressed by mucin-type glycopeptide suppressors (supprescins A and B) prepared from pycnospore germination fluid of Mycosphaerella pinodes, causal agent of Mycosphaerella blight of pea. Here, we show that superoxide dismutase (SOD) in the apoplast fluid/cell wall of pea seedlings responds to the fungal elicitor and suppressor molecules. In a pharmacological study and with internal amino acid sequencing, the apoplastic SOD in a pea cultivar Midoriusui was found to be a Cu/Zn type SOD. We cloned a full-length cDNA of the Cu/Zn-SOD and designated it as PsCu/Zn-SOD1. An increase in PsCu/Zn-SOD1 mRNA and the PsCu/Zn-SOD1 protein was induced by treatment with the elicitor more intensively than by wounding. Such induction by the elicitor or wounding, however, was inhibited by the concomitant presence of supprescins. The SOD activity of recombinant PsCu/Zn-SOD1 was regulated directly by these signal molecules in a manner similar to their effect on the SOD activity in the apoplastic fluid and in the cell wall-bound proteins. Based on these findings, we discuss a role for PsCu/Zn-SOD1 in the pea defense response. The nucleotide sequence data of PsCu/Zn-SOD1 reported are available in the DDBJ/EMBL/GenBank databases under accession number AB189165.     

Cultivar identification of rice (Oryza sativa L.) by polymerase chain reaction method and its application to processed rice products

As the cultivars of rice markedly affect eating quality, processing suitability, and price, identification or differentiation of rice cultivar is very important. We developed suitable 14 STS (sequence-tagged site) primers for PCR (polymerase chain reaction), and it became possible to differentiate 60 Japanese dominant rice cultivars from each other using template DNA extracted and purified from rice grains. A multiplex primer set was shown to be useful to effectively differentiate rice cultivars produced in various countries by PCR. A novel multiplex primer set for PCR has been developed to differentiate KoshihikariBL, which is closely related with the premium cultivar, Koshihikari, in Japan. The application of the cultivar identification method by PCR method to commercially processed rice products was investigated. We developed an enzyme treatment method, in which the gelatinized starch is decomposed by the heat-stable alpha-amylase at 80 degrees C, followed by the hydrolysis of proteins by proteinase K with sodium dodecyl sulfate and purification of extracted DNAs by phenol/chloroform/iso-amyl alcohol. It became possible to identify the material rice cultivars of the commercially processed rice products, such as cooked rice, rice cake, or rice cracker, by a PCR method using template DNA prepared by the enzyme treatment method and novel multiplex primer sets.     

Resetting central and peripheral circadian oscillators in transgenic rats

In multicellular organisms, circadian oscillators are organized into multitissue systems which function as biological clocks that regulate the activities of the organism in relation to environmental cycles and provide an internal temporal framework. To investigate the organization of a mammalian circadian system, we constructed a transgenic rat line in which luciferase is rhythmically expressed under the control of the mouse Per1 promoter. Light emission from cultured suprachiasmatic nuclei (SCN) of these rats was invariably and robustly rhythmic and persisted for up to 32 days in vitro. Liver, lung, and skeletal muscle also expressed circadian rhythms, which damped after two to seven cycles in vitro. In response to advances and delays of the environmental light cycle, the circadian rhythm of light emission from the SCN shifted more rapidly than did the rhythm of locomotor behavior or the rhythms in peripheral tissues. We hypothesize that a self-sustained circadian pacemaker in the SCN entrains circadian oscillators in the periphery to maintain adaptive phase control, which is temporarily lost following large, abrupt shifts in the environmental light cycle.     

Plant regeneration from protoplasts of Iris hollandica Hort.

The effects of glucose concentrations, different sugars and combinations of 2,4-D and kinetin on cell division and colony formation were examined in cultures of protoplasts isolated enzymatically from suspension cultures of Iris hollandica N6 medium supplemented with 1 mg/l 2,4-D, 1 mg/l kinetin, 200 mg/l casein hydrolysate, 250 mg/l proline, 0.3– 0.5 M glucose and 20 g/l agarose was suitable for cell division and colony formation. When colonies formed were transferred to hormone-free MS medium, many shoots were induced. In addition, when induced shoots were transferred to MS medium with 1 mg/l NAA, root induction was observed. A plant regeneration system from protoplasts of I. hollandica was thus established.     

Characteristics of pregelatinized ae mutant rice flours prepared by boiling after preroasting

As ae mutant rice, such as EM10, lacks the starch branching enzyme IIb, its amylopectin contains more long-chain glucans than that of ordinary Indica and Japonica rice grains. Although boiled grains of ae rice cultivars are too hard and nonsticky for table rice, they are promising in terms of biofunctionality, such as prevention of diabetes. The present paper investigates the characterization of a novel group of four ae mutant rice cultivars (EM72, EM145, EM174, and EM189). They were subjected to the evaluation for their main chemical components, physical properties, and enzyme activities at different grain conditions (raw milled rice, roasted rice, boiled rice, and rice boiled after preroasting). These mutant rice grains are characterized by high apparent amylose, high protein and high glucose contents, high pasting temperature, high α-amylase activities, high resistant starch, and low degree of gelatinization. A novel method was developed to maintain the high resistant starch contents of gelatinized rice grains. Rice boild after preroasting showed a higher ratio of resistant starch and a lower amount of glucose than ordinary boiled rice. It became possible to produce high-quality and biofunctional pregelatinized rice flours by boiling with frozen fruits, such as tomatoes, after rice grains had been preroasted. These ae mutants were found to be suitable materials for rice/fruit or rice/vegetable products to serve as palatable, low-glucose, and high resistant starch rice products.     

Physiological characteristics of blue sac disease in chum salmon alevins

Fisheries Science - Blue sac disease (BSD) in salmonids results in the abnormal accumulation of ascites fluid and can often lead to mass mortality. However, the symptoms and causes of BSD remain...     

Morphological and photosynthetic responses of Quercus crispula seedlings to high-light conditions

We investigated morphological and photosynthetic responses of current-year seedlings of oak (Quercus crispula Blume) under high-light conditions. Quercus crispula seedlings were grown from seed in a relative photosynthetically active photon flux density (RPPFD) of 100, 10 or 2%. There was no difference in total dry mass between 100 and 10% RPPFD. At the end of the growing season, plants grown in 2% RPPFD had a lower total dry mass than those grown in 100 or 10% RPPFD. Seedlings grown in 100% RPPFD showed morphological acclimation, i.e., high root/shoot ratios and high leaf mass per area. De-epoxidation level in the xanthophyll cycle and activity of an antioxidant enzyme were highest in 100% RPPFD, but total chlorophyll concentration and photosynthetic rate were highest in 10% RPPFD. These results indicate that excess photons were generated in 100% RPPFD, leading to increased capacities for dissipation of received light energy through the xanthophyll cycle and for scavenging of reactive oxygen species through the water-water cycle. Nevertheless, a midday decrease in dark-adapted quantum yield of photosystem II (F(v)/F(m)) indicated that seedlings grown in 100% RPPFD were suffering from photoinhibition. We conclude that Q. crispula current-year seedlings have high morphological acclimation to high light but that photosynthetic efficiency cannot be maintained under high-light conditions even with a photoprotection system.     

Novel preparation method of template DNAs from wine for PCR to differentiate grape (Vitis vinifera L.) cultivar

Template DNAs were extracted from wine and purified for use as samples for PCR to differentiate grape cultivars. It has been pointed out that the authentication of grape material by PCR using wine as a material is very difficult. The problems are (1) decomposition of DNAs during fermentation; (2) contamination of DNAs from microorganisms such as yeast; (3) interference of DNA extraction by polysaccharides and polypeptides in the beverages; and (4) coexistence of PCR inhibitors, such as polyphenols. For this study was developed a novel preparation method of template DNA from wine to differentiate grape cultivars using PCR by (1) lyophilizing and pulverizing the fermented beverage to concentrate the DNAs; (2) decomposition of polysaccharides and proteins so as not to inhibit DNA extraction using heat-resistant amylase and proteinase K without DNA damage by endogenous DNase; and (3) separation of the template DNAs for PCR from PCR inhibitors, such as polyphenols, by purification using 70% EtOH extraction and isopropyl alcohol precipitation. To prevent the amplification of microorganisms' DNAs during PCR, suitable PCR primers closely related to the specific plant DNAs, such as chloroplast DNA and mitochondrial DNA, were selected. The sequences of the amplified DNAs by PCR were ascertained to be the same as those of grape materials.     

Quality Prediction of Rice Flour by Multiple Regression Model with Instrumental Texture Parameters of Single Cooked Milled Rice Grains

The purpose of this study was to develop highly accurate regression models with texture parameters of cooked milled rice grains for predicting pasting properties in terms of quality index of rice flour. Two methods were adopted as the texture measurement to acquire predictors for the models. In the calibration set, all the multiple regression models by a single‐grain method exhibited a higher R² than those by a three‐grain method. Each of the former models also showed a lower SEP and a higher RPD in the validation set. The prediction performance was best for consistency (RPD = 2.4). The single‐grain method was more advantageous for the pasting prediction. These results suggest that the models based on grain texture could predict rice flour quality.