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81.
Takahashi H Kobayashi T Sato-Nara K Tomita KO Ezura H 《Journal of experimental botany》2002,53(368):415-422
Antibodies against melon ethylene receptor, Cm- ERS1 was prepared. Cm-ERS1 protein formed a disulphide-linked homodimer and it was present in microsomal membranes but not in soluble fractions. Cm-ERS1 protein was present at high levels in melon fruit during early developmental stages. This transition pattern was also observed in another melon cultivar. 相似文献
82.
Sagane Y Watanabe T Kouguchi H Sunagawa H Obata S Oguma K Ohyama T 《Biochemical and biophysical research communications》2002,292(2):434-440
The nontoxic-nonhemagglutinin (NTNHA) component, in both isolated form and the neurotoxin (NT)/NTNHA complexed form, was prepared protease-free from toxin complexes produced by Clostridium botulinum type D strain 4947. NTNHA in both preparations was found to be spontaneously converted to the nicked NTNHA form leading to 15- and 115-kDa fragments with the excision of several amino acid residues at specific sites on SDS-PAGE during long-term incubation, while that of the NT/NTNHA/hemagglutinin complexed form remained unnicked single-chain polypeptides under the same conditions. Considering that the NTNHA preparation contained small amounts of the nicked form of NTNHA and the addition of trypsin accelerated the cleavage, it is speculated that a nicked form of NTNHA remaining after the purification and/or NTNHA itself catalyzes the cleavage of intact NTNHA. 相似文献
83.
The yeast Candida boidinii PEP4 and PRB1 genes, encoding proteinase A (PrA) and proteinase B (PrB), respectively, have been cloned and their primary structures were analyzed. The open reading frames of the PEP4 gene (1263 bp encoding a protein of 420 amino acids) and the PRBI gene (1683 bp encoding a protein of 560 amino acids) were found. The deduced amino acid sequences of PrA and PrB are very similar to Saccharomyces cerevisiae PrA and PrB (64% and 61% identities, respectively). Both PEP4 and PRBI genes were disrupted in the C. boidinii genome by one-step gene disruption. The resultant pep4delta and the pep4delta prb1delta strains lost protease activity when compared with the wild-type original strain. The constructed C. boidinii strains are expected to be useful hosts for heterologous protein production. 相似文献
84.
Michishita E Matsumura N Kurahashi T Suzuki T Ogino H Fujii M Ayusawa D 《Bioscience, biotechnology, and biochemistry》2002,66(4):877-879
We tested various thymidine analogues for induction of a senescence-like phenomenon in HeLa cells. CldU, BrdU, and IdU similarly induced the morphology of senescent cells and typical senescence markers. Thymidine analogues other than 5-halogenated forms caused only cell death. BrdU efficiently killed the cells in cooperation with irradiation with light and a brief treatment with Hoechst 33258, but CldU did not at all. 5-Halogenated thymidine analogues were thus shown to be specific inducers of cellular senescence in mammalian cells. 相似文献
85.
Kazuo Sasaki Tatsuaki Ishise Koichiro Shimomura Toshihiro Kobayashi Yoshikatsuo Matsubayashi Youji Sakagami Hironori Umetsu Hiroshi Kamada 《Plant Growth Regulation》2002,36(1):87-90
Phytosulfokine (PSK)- is a sulphated pentapeptide, isolated fromthe medium of cultured Asparagus officinalis mesophyllcells, that promotes cell proliferation. It is a putative key factor inconditioned medium required for the growth of low-density plant cell cultures.The present study investigates the effect of PSK- on growth and tropanealkaloid production in Atropa belladonna hairy rootstransformed with Agrobacterium
rhizogenes (MAFF 03-01724). Although the growth rates ofhairy roots cultured in medium with orwithout PSK- for 4 weeks did not show any differences, the productivityof tropane alkaloids, especially of hyoscyamine, was enhanced by10–7 or 10–8 M PSK-. Inaddition, the content of tropane alkaloids in transformed roots treated withPSK- was 1.4 times higher than that of untreated roots after 4 weeks ofculture. The time course of growth and tropane alkaloid production inAtropa belladonna transformed roots suggested thatPSK- influenced the growth of transformed roots during the activegrowingphase, but not tropane alkaloid production. 相似文献
86.
Regulation of angiogenesis by the aging suppressor gene klotho 总被引:5,自引:0,他引:5
Fukino K Suzuki T Saito Y Shindo T Amaki T Kurabayashi M Nagai R 《Biochemical and biophysical research communications》2002,293(1):332-337
Advanced age is a major risk factor of peripheral artery disease. We examined the effects of the aging-suppressor gene klotho on angiogenesis in response to ischemia by introducing ischemic hindlimb model in mice heterozygously deficient for the klotho gene and in wild type mice. Blood flow recovery as assessed by laser doppler perfusion imaging and angiogenesis as assessed by density of PECAM-1/CD31-positive positive capillaries were markedly impaired in mice heterozygously deficient for the klotho gene (both <0.05). Our findings show that the aging-suppressor gene klotho affects angiogenesis and the possibility that age-related impairment of angiogenesis might be regulated by the klotho gene. Our results present a new possibility of therapeutic angiogenesis for patients of advanced age. 相似文献
87.
The obesity in bilateral ovariectomized rats is related to a decrease in the expression of leptin receptors in the brain. 总被引:4,自引:0,他引:4
Mitsuhiro Kimura Minoru Irahara Toshiyuki Yasui Seiichiro Saito Michiko Tezuka Shuji Yamano Masaharu Kamada Toshihiro Aono 《Biochemical and biophysical research communications》2002,290(4):1349-1353
We investigated the expression levels of leptin receptors in the brain of ovariectomized (OVX) rats. The mean expression level of ob mRNA in adipose tissues of OVX rats was significantly (P < 0.01) lower than that in the SHAM operation group rats, and the mean body weight of OVX rats was significantly (P < 0.01) greater than that in the SHAM group rats. However, there were no differences between serum leptin concentrations in these two groups. The mean level of leptin receptor (OB-R) mRNA expression in the brain tissue and the mean level of long form type OB-R (OB-RL) mRNA expression in the hypothalamus of the OVX rats were significantly (P < 0.05) lower than those in the SHAM group rats. These changes were cancelled by supplementation with 17 beta-estradiol in OVX rats. These results suggested that not only changes in the expression level of ob mRNA in adipose tissue and the serum leptin concentration but also changes in the OB-R mRNA in the brain are involved in the body weight increase in OVX rats and that a decrease in OB-R makes transmission of signals to suppress the amount of food intake difficult, thus leading to an increase in body weight. 相似文献
88.
89.
Thelephantins D-H: five p-terphenyl derivatives from the inedible mushroom Thelephora aurantiotincta
Ngoc Quang D Hashimoto T Hitaka Y Tanaka M Nukada M Yamamoto I Asakawa Y 《Phytochemistry》2003,63(8):919-924
Five p-terphenyl derivatives named thelephantins D-H (1-5) together with nine known compounds, thelephantins A-C (6-8), ganbajunin E (9), p-hydroxylbenzoic acid (10), ganbajunin C (11), thelephorin A (12), 2-O-methylatromentin (13) and atromentin (14), were isolated from the methanolic extract of fruit bodies of the Thelephoraceous Basidiomycete Thelephora aurantiotincta. Their structures were elucidated by high-resolution MS, 2D NMR, IR and UV spectroscopic analysis. 相似文献
90.
The hydrodistillation products of the liverwort Bazzania japonica were separated by preparative gas chromatography (GC) and investigated by spectroscopic methods. Seven unknown compounds were isolated and identified by GC-MS and NMR. Four of them, the norsesquiterpene hydrocarbons 4-epi-11-nor-aristola-1(10),11-diene (1), 4-epi-11-nor-aristola-1,9,11-triene (2), 4-epi-11-nor-aristola-9,11-diene (3), and one oxygenated sesquiterpene, (-)-aristol-1(10)-en-12-ol (5) are new natural compounds, and one, (+)-himachala-2,4-diene (7), has for the first time been isolated from liverworts. The absolute configurations of 5 and 7 were derived by chemical correlation reactions and/or enantioselective GC using cyclodextrin phases. 1, 2 and 3 have identical absolute configuration. 相似文献