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1.
The seasonal change in petal color and pigmentation of 29 commercial Eustoma cultivars was studied. The flowers are basically divided into four groups according to the major anthocyanidin phenotype in association with petal coloration, i.e., delphinidin (Dp)-based (purple flower), cyanidin (Cy)-based (reddish purple flower), pelargonidin (Pg)-based (pink flower), and none (white flower) groups. The constitution of petal anthocyanidins was not changed by forcing treatment in most of the flowers. Lightness (L*) and chroma (C*, color saturation) showed a change along with the increase/decrease of hue angle difference (ΔH*), thus simultaneously the chromatic tonalities tended to move to redder and bluer, respectively. Floral pigment clustering described two flower groups in a dendrogram, based on anthocyanidin constitutions as phenetic markers, which are apparently the Dp- and Pg-based phenotypes of anthocyanidin syntheses. The Cy-based flowers made a subcluster with the Pg-based flowers, indicating a close relationship in the biosynthesis of the two anthocyanidins, and suggesting the Dp- and Pg-syntheses complement one another.  相似文献   
2.
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452 were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably 2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines.  相似文献   
3.
Stabilization of the levels of active oxygen species (AOS) is important to the survival of organisms. To clarify the system controlling levels of AOS in plants, this study used an electron spin resonance (ESR) method to directly measure superoxide radical (O(2)(.-)) scavenging activities in the wild-type Arabidopsis thaliana (Col and Ler ecotypes), two anthocyanin mutants (tt3 and ttg1), and an ascorbic acid mutant (vtc1). Under ordinary growth conditions, Arabidopsis contained superoxide-scavenging activity (SOSA) of approximately 300-500 SOD units/g of fresh weight. The ESR pattern indicated that most (40-50%) of this activity was due to ascorbic acid. For the analysis of SOSA under conditions of oxidative stress, synthesis of AOS was induced by gamma-irradiation. The radical scavenging activity in irradiated plants increased approximately 10-fold following an associated increase in the accumulation of ascorbic acid and anthocyanin. The accumulation of ascorbic acid and anthocyanin was suppressed by treatment with an antioxidant before irradiation and was induced by treatment with a radical-generating reagent. The contributions of ascorbic acid and anthocyanin to the total superoxide radical scavenging activity differed among ecotypes. In the Ler ecotype, ascorbic acid accumulated at twice the level of that in the Col ecotype, and induction of anthocyanin was half that in Col. To confirm the activity of ascorbic acid and anthocyanin against AOS stress, the viability of the wild type and mutants (tt2, tt3,tt5, ttg1, and vtc1) was examined after gamma-irradiation. Only the plants in which ascorbic acid and anthocyanin were induced had the ability to grow and flower.  相似文献   
4.
We previously identified a novel gonad-specific expression gene (Gse) and investigated its expression during gametogenesis in the mouse testis and ovary. In this study, we generated a polyclonal antibody to GSE protein and determined the profiles of the protein's expression in germ cells and preimplantation embryos in detail using immunocytochemical and immunofluorescence staining. In a Western blot analysis, the anti-GSE antibody recognized long and short isoforms (approximately 27.6 kDa and 23.1 kDa) of the protein in the mouse testis and the long isoform in the ovary. In the mouse testis, GSE protein was expressed in spermatocytes I in the pachytene stage, round spermatids, and elongated spermatids. In the mouse ovary, the protein was located in the cytoplasm and nucleus of all oocytes regardless of the stage of the ovarian follicles. In preimplantation embryos from the pronuclear to blastocyst stage, however, GSE protein was mainly detected in the nuclei of cells. At the blastocyst stage, the protein was confirmed to have accumulated in the inner cell mass (ICM), whereas it had mostly disappeared from the trophectoderm (TE). These findings suggest that GSE protein may play a role in the establishment of nuclear totipotency and may be associated with early lineage specification.  相似文献   
5.
The viscoelastic properties and molecular structure of the starch isolated from waxy (amylose-free) hexaploid wheat (WHW) (Triticum aestivum L.) were examined. WHW starch generally had lower gelatinization onset temperature, peak viscosity, and setback than the starch isolated from normal hexaploid wheat (NHW). Differential scanning calorimetry (DSC) showed that WHW starch had higher transition temperatures (To, Tp, and Tc) and enthalpy (ΔH) than NHW starch. However, when compared on the basis of amylopectin (AP) content, ΔH of WHW starch was almost statistically identical to that of its parental varieties. Typical A-type X-ray diffraction patterns were observed for the starches of WHW and its parental varieties. Somewhat higher crystallinity was indicated for WHW starch. WHW starch was also characterized by having greater retrogradation resistance. The high-performance size-exclusion chromatography (HPSEC) of amylopectin showed that each amylopectin yielded two fractions after debranching. Although WHW amylopectin had somewhat long B chains, little difference was observed in the ratio of Fr.III/ Fr.II between WHW and its parental varieties.  相似文献   
6.

Backgrounds

The aim of this study was to confirm the propagation of various canine distemper viruses (CDV) in hamster cell lines of HmLu and BHK, since only a little is known about the possibility of propagation of CDV in rodent cells irrespective of their epidemiological importance.

Methods

The growth of CDV in hamster cell lines was monitored by titration using Vero.dogSLAMtag (Vero-DST) cells that had been proven to be susceptible to almost all field isolates of CDV, with the preparations of cell-free and cell-associated virus from the cultures infected with recent Asian isolates of CDV (13 strains) and by observing the development of cytopathic effect (CPE) in infected cultures of hamster cell lines.

Results

Eleven of 13 strains grew in HmLu cells, and 12 of 13 strains grew in BHK cells with apparent CPE of cell fusion in the late stage of infection. Two strains and a strain of Asia 1 group could not grow in HmLu cells and BHK cells, respectively.

Conclusion

The present study demonstrates at the first time that hamster cell lines can propagate the majority of Asian field isolates of CDV. The usage of two hamster cell lines suggested to be useful to characterize the field isolates biologically.  相似文献   
7.
Ethanol was produced from the hydrolysate collected as a water-soluble (WS) portion and a residue after hot-compressed water (HCW) treatment of Japanese beech with and without fractionation. Simultaneous saccharification with β-xylosidase and isomerization with xylose isomerase followed by fermentation with Saccharomyces cerevisiae were applied to the WS portion; simultaneous saccharification with cellulase and fermentation with S. cerevisiae was applied to the residue. Integration of the processes for the WS portion and the residue was investigated to improve the conversion efficiency throughout the whole process. The ethanol yield in the integrated process without fractionation was comparable with that for the process with fractionation. Ethanol yields were improved for both of the processes by modifying the operation pattern in which cellulase was added prior to fermentation of the residue.  相似文献   
8.
Sweet wheat (SW), which lacks functional granule-bound starch synthase I (GBSSI) and starch synthase IIa (SSIIa), accumulates high levels of free sugars in immature seeds. Here, we examined the effects of the lack of these two enzymes on mature kernel composition. Whole grain flour of SW had higher levels of sugars, particularly maltose, slightly higher ash and protein content, approximately two to three times higher lipid levels, and about twice as much total dietary fiber as parental or wild-type lines. Considerably higher levels of low-molecular-weight soluble dietary fiber (LMW-SDF), largely consisting of fructan, were also detected in SW. Although there were no differences in total amino acid levels, the free amino acid content of SW was approximately 4-fold higher than that of wild type, and the levels of certain free amino acids such as proline were particularly high. Thus, we were able to clearly demonstrate that the lack of GBSSI and SSIIa caused dramatic changes in mature seed composition in SW. These compositional changes suggest that SW flour may provide health benefits when used as a food ingredient.  相似文献   
9.
More than 7000 red algae species have been classified. Although most of them are underused, they are a protein-rich marine resource. The hydrolysates of red algal proteins are good candidates for the inhibition of the angiotensin-I-converting enzyme (ACE). The ACE is one of the key factors for cardiovascular disease, and the inhibition of ACE activity is related to the prevention of high blood pressure. To better understand the relationship between the hydrolysates of red algal proteins and the inhibition of ACE activity, we attempted to identify novel ACE inhibitory peptides from Pyropia pseudolinearis. We prepared water soluble proteins (WSP) containing phycoerythrin, phycocyanin, allophycocyanin, and ribulose 1,5-bisphosphate carboxylase/oxygenase. In vitro analysis showed that the thermolysin hydrolysate of the WSP had high ACE inhibitory activity compared to that of WSP. We then identified 42 peptides in the hydrolysate by high-performance liquid chromatography and mass spectrometry. Among 42 peptides, 23 peptides were found in chloroplast proteins. We then synthesized the uncharacterized peptides ARY, YLR, and LRM and measured the ACE inhibitory activity. LRM showed a low IC50 value (0.15 μmol) compared to ARY and YLR (1.3 and 5.8 μmol). In silico analysis revealed that the LRM sequence was conserved in cpcA from Bangiales and Florideophyceae, indicating that the novel ACE inhibitory peptide LRM was highly conserved in red algae.  相似文献   
10.
Indian dwarf wheat (Triticum aestivum L. ssp. sphaerococcum (Perc.) Mac Key, synonym: T. sphaerococcum Perc.) is endemic to southern Pakistan and northwestern India. It was one of the main winter crops grown by ancient Indian cultures. However, it disappeared from the record during the early twentieth century, especially after the Green Revolution brought modern wheat varieties into India and Pakistan. Whether or not Indian dwarf wheat is presently cultivated has been unclear. Here we report on the rediscovery of the cultivation of this wheat in northern Karnataka and southern Maharashtra in India. Molecular genetic analysis of the chloroplast DNA of the two specimens collected at location 3 revealed that both samples have a unique haplotype that is specific to Indian dwarf wheat. We found this wheat at three locations in 2010, but at only one of the three locations in 2011. Therefore, the future survival of this subspecies is uncertain. Further ethnobotanical research is urgently needed to conserve this unique genetic resource for the future.  相似文献   
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