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11.
Ishikawa Keiko; Kamada Hiroshi; Yamaguchi Isomaro; Takahashi Nobutaka; Harada Hiroshi 《Plant & cell physiology》1988,29(3):461-466
Carrot and tobacco plants were transformed with Agrobacteriumtumefaciens harboring wild-type, aux or cyt Tiplasmids. In tobacco, these wild and mutant Ti plasmids inducedthe formation of non-morphogenic galls, galls with shoots, andgalls with roots, respectively. In carrot, however, transformationwith any of these plasmids resulted in only the formation ofamorphous tumors. Determination of IAA and cytokinin contentsshowed that in tobacco, significantly high amounts of cytokininsor IAA are present in the cells transformed with Ti plasmidspossessing cytokinin or IAA biosynthetic genes, respectively.In carrot, cytokinin contents were also high in the cells transformedwith Ti plasmids having cytokinin biosynthetic genes, whereasIAA contents of the cells were similar regardless of the plasmidsused for transformation. These results suggest that the mechanism regulating IAA metabolismmay be different in tobacco and carrot. (Received June 25, 1987; Accepted February 1, 1988) 相似文献
12.
IAA biosynthetic activity was examined in cultured carrot tissuestransformed with Agrobacterium tumefaciens harboring wild-type,aux or cyt Ti plasmids. In vitro IAAM hydrolaseactivities in tissues transformed with wild-type, and cytTi plasmids were 3.09 and 19.82 nmol/g proteins/30 min, respectively,but not detectable when aux Ti plasmids were used. Theactivity of IAA biosynthesis, determined by the incorporationof radioactivity into IAA in tissues fed with [14C]-tryptophan,was 34.13, 10.92 and 32.47 pmol/g fr wt/30 min in tissues transformedwith wild type, aux and cyt Ti plasmids, respectively.The incorporation of radioactivity into the IAAM fraction wasdetected only in the tissues transformed with wild type andcyt Ti plasmids. These results showed that the T-DNAencoded pathway of IAA biosynthesis was active in tissues transformedwith wild-type and cyth Ti plasmids, and that the activity ofIAA biosynthesis in those tissues was higher than that in tissuestransformed with the aux Ti plasmid. (Received March 16, 1988; Accepted July 31, 1988) 相似文献
13.
Oncogenic transformation by fractionated doses of neutrons 总被引:1,自引:0,他引:1
R C Miller D J Brenner C R Geard K Komatsu S A Marino E J Hall 《Radiation research》1988,114(3):589-598
Oncogenic transformation was assayed after C3H 10T1/2 cells were irradiated with monoenergetic neutrons; cells were exposed to 0.23-, 0.35-, 0.45-, 5.9-, and 13.7-MeV neutrons given singly or in five equal fractions over 8 h. At the biologically effective neutron energy of 0.45 MeV, enhancement of transformation was evident with some small fractionated doses (below 1 Gy). When transformation was examined as a function of neutron energy at 0.5 Gy, enhancement was seen for cells exposed to three of the five energies (0.35, 0.45, and 5.9 MeV). Enhancement was greatest for cells irradiated with 5.9-MeV neutrons. Of the neutron energies examined, 5.9-MeV neutrons had the lowest dose-averaged lineal energy and linear energy transfer. This suggests that enhancement of transformation by fractionated low doses of neutrons may be radiation-quality dependent. 相似文献
14.
15.
Keiko Mori Kazuho Hirata Masaru Kawabuchi Manabu Nakashima Takeshi Watanabe 《Immunogenetics》1991,33(2):101-107
A monoclonal antibody (mAb) TP-3 has been established by immunizing rats with the BALB/c mouse thymic epithelial cell line TEL-2. The TP-3 antigen is expressed on stroma cells of thymus, spleen, and lymph node in syngeneic BALB/c mice (H-2
d
). This antigen is also expressed at a low level on the cell surface of immature thymocytes, and at a high level on mature T and B cells. In allogeneic mice such as C57BL/6 (H-2
b
) or C3H (H-2
k
), no cells expressed the TP-3 antigen. Using H-2 congenic mice, reactivity with mAb TP-3 was found to map to a region of H-2D
d
L
d
or between D
d
and Qa, suggesting that TP-3 is a major histocompatibility complex (MHC) class I antigen. However, immunoprecipitation analysis indicated that this antigen is not identical to the classical mouse class I molecules in terms of molecular size, antigenicity, and tissue distribution. 相似文献
16.
Michiaki Morohashi Keiko Tsuchiya Takashi Mita Masaru Kawamura 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(1):69-72
Summary An inhibitory activity to (Na,K)ATPase was found in cell extracts of the brine shrimp, Artemia salina, irrespective of its developmental stages. Organic solvent extraction together with gas chromatographic analysis reveals that the inhibitory activity is due to long-chain, non-esterified fatty acids and their derivatives. Unsaturated fatty acids, especially with cis-configuration, are more effective in inhibition than saturated ones.Abbreviations ATPase
adenosine triphosphatase
- EDTA
ethylenediamine-tetraacetate
- TLC
thin-layer chromatography 相似文献
17.
Weng Kong Sung Masanobu Komatsu Georgiana M. Jagiello 《Molecular reproduction and development》1986,14(3):245-254
A combination of autoradiography and air-dried techniques was used to calculate the duration of the major meiotic stages in the first wave of spermatogenesis in the newborn mouse. The data indicated that the entry into meiosis occurred asynchronously over 2 days, and the time required for each stage and the total cycle was constant. These time intervals were nearly identical with those estimated for adult animals in the present study and by other authors. 相似文献
18.
Polymorphism of soluble aconitase was investigated in 152 Japanese placentae. The allelic frequencies were ACONS1 = 0.951 and ACONS2 = 0.049. ACONS2 appears to be rather high among Orientals including Japanese, while ACONS4 seems to be characteristic for Negroids. 相似文献
19.
W Nakamura K Komatsu K Kageyama 《Comptes rendus des séances de la Société de biologie et de ses filiales》1985,179(4):558-562
Comparison was made between the effects of local irradiation of gamma rays, s. c. injection of cis-diamminedichloroplatinum (II) (CDDP), systemic hyperthermia and their combinations on the i. m. transplanted murine mastocytoma. Increase of the mean survival time (M. S. T.) by a factor of 1.72 and of 1.68 was achieved by a single irradiation at 20 Gy, given on day 5 after transplantation, and by injections of CDDP at 2 mg/kg, given s. c. on days 5 and 12 after transplantation, respectively. Increase of M. S. T. by a factor of 1.10 which was achieved with systemic hyperthermia of 41.8 degrees C of the core body temperature for 5 min, given twice, on days 5 and 12 after transplantation, was not statistically significant. The most effective one among all possible combinations within the 3 modalities was that of radiation and CDDP. Increase of M. S. T. was by a factor of 4.01. 相似文献
20.
M. Nakamura M. Oda Y. Yonei N. Tsukada H. Komatsu K. Kaneko M. Tsuchiya 《Histochemistry and cell biology》1985,83(6):479-487
Summary The muscarinic cholinergic innervation of the rat gastric mucosa was investigated by localizing the muscarinic receptors using a tritiated muscarinic antagonist, pirenzepine. Radioautography was performed by freeze drying stomach tissue, which was then embedded in Epon and wet sectioned with ethylene glycol, and dry mounting on emulsion film by the wire-loop method to prevent loss of the labelled substance during fixation and the radioautographic procedure. Light and electron microscopy showed that the specific pirenzepine-binding sites were localized predominantly on parietal cells, chief cells and perivascular plexuses. Analysis of the grain distribution on parietal cells revealed that the silver grains corresponding to the pirenzepine-binding sites were mainly on the basolateral plasma membrane. On the other hand, the surface mucous or mucous neck cells had few pirenzepine-binding sites. 相似文献