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21.
Cloning and expression of flavonol synthase from Petunia hybrida 总被引:10,自引:0,他引:10
Timothy A. Holton Filippa Brugliera Yoshikazu Tanaka 《The Plant journal : for cell and molecular biology》1993,4(6):1003-1010
Flavonols are important co-pigments in flower colour and are also essential for pollen tube growth. In petunia, flavonol synthesis is controlled by the Fl locus. Flavonol synthase (FLS) belongs to the 2-oxoglutarate-dependent dioxygenase family. Dioxygenase gene fragments were amplified by PCR on cDNA made from FlFl and flfl flowers using degenerate primers designed from conserved dioxygenase sequences. A petunia petal cDNA library was screened for clones that hybridized more strongly to the Fl PCR products than the fl PCR products. A full-length cDNA clone identified by this screening exhibited FLS activity when expressed in yeast. FLS gene expression is developmentally regulated during flower development. Antisense expression of an FLS cDNA clone in petunia markedly reduced flavonol synthesis in petals. RFLP mapping showed that the FLS gene is linked to Fl , suggesting that Fl is the structural gene for FLS. 相似文献
22.
Kazunori Yokoi Yoshiaki Yasumizu Naganari Ohkura Koei Shinzawa Daisuke Okuzaki Nene Shimoda Hideya Ando Nanako Yamada Manabu Fujimoto Atsushi Tanemura 《Pigment cell & melanoma research》2023,36(5):355-364
Vitiligo is a common depigmentation disorder characterized by the selective loss of melanocytes. In our daily clinic experience, we noticed that the skin tightness of hypopigmented lesions would be more evident in comparison to that of uninvolved perilesional skin in vitiligo patients. Therefore, we hypothesized that collagen homeostasis might be maintained in vitiligo lesions, irrespective of the substantial excessive oxidative stress that occurs in association with the disease. We found that the expression levels of collagen-related genes and anti-oxidative enzymes were upregulated in vitiligo-derived fibroblasts. Abundant collagenous fibers were observed in the papillary dermis of vitiligo lesions in comparison to uninvolved perilesional skin by electron microscopy. The production of matrix metalloproteinases that degraded collagen fibers was suppressed. The deposition of acrolein adduct protein, which is a product of oxidative stress, was significantly reduced in vitiligo dermis and fibroblasts. As part of the mechanism, we found upregulation of the NRF2 signaling pathway activity, which is an important defense system against oxidative stress. Taken together, we demonstrated that the anti-oxidative action and collagen production were upregulated and that the collagen degeneration was attenuated in vitiligo dermis. These new findings may provide important clues for the maintenance of antioxidant ability in vitiligo lesions. 相似文献
23.
Motohiro Matsuura Shinji Saito Yoshikazu Hirai Haruki Okamura 《European journal of biochemistry》2003,270(19):4016-4025
Production of nitric oxide (NO) in response to bacterial lipopolysaccharide (LPS) was investigated using cultures of mouse peritoneal exudate cells (PEC) and the macrophage cell line RAW264.7. In the presence of anti-(interferon-gamma) (IFN-gamma), NO production was markedly suppressed in the PEC culture but not in the RAW264.7 culture. In the PEC culture, LPS induced both IFN-gamma production and activation of IFN response factor-1, which leads to the gene expression of inducible NO synthase, but neither was induced in the culture of RAW264.7 cells. In addition to anti-(IFN-gamma), antibodies against interleukin (IL)-12 and IL-18 showed a suppressive effect on LPS-induced NO production in the PEC culture, and these antibodies in synergy showed strong suppression. Stimulation of the PEC culture with IL-12 or IL-18 induced production of IFN-gamma and NO, and these cytokines, in combination, exhibited marked synergism. Stimulation of the culture with IFN-gamma induced production of NO, but not IL-12. The macrophage population in the PEC, prepared as adherent cells, responded well to LPS for IL-12 production, but weakly for production of IFN-gamma and NO. The macrophages also responded well to IFN-gamma for NO production. For production of IFN-gamma by stimulation with LPS or IL-12 + IL-18, nonadherent cells were required in the PEC culture. Considering these results overall, the indirect pathway, through the production of intermediates (such as IFN-gamma-inducing cytokines and IFN-gamma) by the cooperation of macrophages with nonadherent cells, was revealed to play the main role in the LPS-induced NO production pathway, as opposed to the direct pathway requiring only a macrophage population. 相似文献
24.
Yoshikazu Nagata Tadashi Tetsukawa Takanori Kobayashi Ken-ichi Numachi 《Ichthyological Research》1996,43(2):117-124
Eleven populations of the rosy bitterling,Rhodeus ocellatus, from different localities in Japan, were genetically compared at 16 protein-coding loci using starch-gel electrophoresis.
Two loci,Ldh-2 andPgdh, were demonstrated as diagnostic markers for the identification of two subspecies;R. ocellatus kurumeus, which is native to Japan, andR. ocellatus ocellatus, which was introduced from China. The two subspecies were distinguished by the complete substitution of different alleles
between them. Population ofR. ocellatus kurumeus occurring in Yao City, Osaka, and in Kanzaki, Saga Prefecture were genetically closely related to each other (genetic distance:
D=0.056) but distantly so toR. ocellatus ocellatus from Saitama Prefecture (D=0.202 or 0.265). Electrophoretic analyses also elucidated the existence of hybrid populations
of the two subspecies. The populations ofR. ocellatus kurumeus in Yao City had lower genetic variability and a lower incidence of white coloration on the ventral fins than populations
of the same in Saga Prefecture. The present study strongly implies that the introduction of the foreign freshwater fishes
with subspecific differentiation, into the original range of indigenous subspecies, should be averted not to bring the genetic
pollution. 相似文献
25.
26.
Nobuhiro Kanno Minoru Sato Eizou Nagahisa Yoshikazu Sato 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,114(4):409-416
This is the first report of the purification of tauropine dehydrogenase (NAD: tauropine oxidoreductase) from a polychaete worm. In the sandwormArabella iricolor Montagu (Polychaet: Errantia), two forms of TaDH were detected: major component (pl = 7.5) and minor one (pI = 6.4). The major TaDH component was purified to homogeneity by means of (NH4)2SO4 precipitation, anion-exchange, affinity, chromatofocusing and hydrophobic chromatography, and characterized. From the molecular mass of 43.7 kDa obtained by rapid gel-filtration and that of 43.5 kDa by SDS-PAGE, the sandworm enzyme appeared to be a monomeric protein. Maximum rates of reduction of pyruvate and oxidation of tauropine were observed at pH 7.0 and 8.5, respectively. Pyruvate and taurine were preferred substrate for the enzyme. Apparent Km values determined using constant co-substrate concentrations were: 35.7 mM, 0.34 mM, and 0.036 mM for taurine, pyruvate and NADH, respectively, in the tauropine synthesizing reaction; and 4.8 mM and 0.051 mM for tauropine and NAD+, respectively, in the tauropine oxidizing reaction. The tauropine synthesizing reaction was subject to substrate inhibition by pyruvate: maximum rate was observed at 2.5–3.0 mM (inhibitory range of pyruvate concentration producing half-maximal rate was 26.8 mM). 相似文献
27.
Yoshikazu Horie Toshimitu Fukiharu Kazuko Nishimura Hideaki Taguchi Duan Li Wang Ruoyu Li 《Mycoscience》1996,37(3):323-329
Emericella miyajii, a new species isolated from Chinese soil, is described and illustrated. It is characterized by pale orange to brownish orange
colonies on malt extract agar, subglobose to broadly elliptical ascospores with defective four equatorial crests and smooth
convex walls, and with anAspergillus anamorph.Emericella undulata is also described as an uncommon species from Chinese soil. 相似文献
28.
29.
Cloning of murine Stat6 and human Stat6, Stat proteins that are tyrosine phosphorylated in responses to IL-4 and IL-3 but are not required for mitogenesis. 总被引:24,自引:5,他引:19 下载免费PDF全文
30.
Purification and characterization of M3 protein expressed on the surface of group A streptococcal type 3 strain C203 总被引:2,自引:0,他引:2
Kyongsu Hong Yoshikazu Komurasaki Hideyuki Kobayashi Hiromichi Ishikawa Kozo Inoue 《FEMS immunology and medical microbiology》1995,12(1):73-82
Abstract Monoclonal antibodies (mAbs) have been produced by immunizing BALB/C mice with whole M+ bacteria in incomplete Freund adjuvant and the resulting mAbs for M3 protein have been selected by an indirect immuno-fluorescent technique using formaldehyde-fixed M+ and M− bacteria. Four mAbs reacted with a 65 kDa protein in an extract obtained from the cell wall of M+ bacteria after treatment with N -acetyl muramidase and lysozyme. The purified 65 kDa protein neutralized the phagocytic activity of rabbit anti-M3 antibody. The N-terminal amino acid sequence of the 65 kDa protein was identical with that of protein generated by the M3 gene which has been previously cloned and sequenced. The evidence indicates that the 65 kDa protein is M3 protein. The M3 protein bound not only human fibrinogen but also human serum albumin (HSA). When the M3 protein was purified by gel-filtration and ion-exchange chromatography in the absence of phenylmethyl sulfonyl fluoride (PMSF), four fragments (35 kDa, 32 kDa, 30 kDa, and 25 kDa) in addition to the intact molecule appeared. N-terminal amino acid sequence analysis showed that 35 kDa and 25 kDa fragments were ANAAD and DARSV, respectively, being identical at positions 1–5 and 198–202 to the M3 gene derived protein. Therefore, the 35 kDa and 25 kDa fragments, which were presumed to be cleavage products, may be derived from the C-terminal part and N-terminal part of the intact molecule, respectively. When the effect of purified M3 protein in the bactericidal activity of normal human blood in the presence of M− bacteria was investigated, the M3 protein was responsible for the organism's resistance to attack by phagocytic cells. 相似文献