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91.
Kato Ryoichi; Takatsuna Sachiko; Wada Tsuyoshi; Narihara Yumi; Suzuki Takashi 《Plant & cell physiology》1996,37(5):667-672
Five-mm sections of elongation zones of Zea mesocotyls wereincubated for designated periods with various concentrationsof IAA. In vitro protein phosphorylation in the soluble fraction(85,000 x g supernatant) prepared from the sections was analyzedby sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The phosphorylation of proteins in the soluble fraction thathad been prepared from sections incubated for 20 min in thepresence of 10{small tilde}s M IAA was greater than that inthe sections incubated for 20 min without IAA. The amount ofphosphorylation of proteins per protein became higher when higherconcentrations increased (10{small tilde}810{small tilde}5M).The growth of sections incubated in the presence of 10{smalltilde}8 M IAA or higher concentrations was greater than thatof sections incubated in the absence of IAA. The promotion ofgrowth by IAA was greater at higher concentrations of IAA. Proteinsin the soluble fraction, prepared from sections incubated for20 min in the presence of 10{small tilde}5 M IAA, were phosphorylatedin the presence of either 10 fM cAMP, 10 µM cGMP, 100µM W-7, 100 µM W-5, 20 µM H-7 or 20 µMHA1004. The calmodulin antagonist, W-7, and the inhibitor ofprotein kinase C, H-7, inhibited the phosphorylation of proteinsstimulated by incubation with IAA. These results suggest thatIAA promotes cell elongation via protein phosphorylation thatdepends on calmodulin-dependent protein kinase and protein kinaseC. (Received November 29, 1995; Accepted May 20, 1996) 相似文献
92.
We investigated the metabolism and translocation of two gibberellins(GAs), [3H]GA20 and [3H]GA1, which were applied at low concentrationto the cotyledons of Pharbitis nil (cv. Violet). Seedlings weregrown under three different photoperiodic conditions: continuouslight (CL-CL), continous light followed by short day conditions(CL-DT) and long day conditions followed by short day conditions(DT-DT). Translocation of the applied [3H]GAs from cotyledonsto hypocotyls was promoted by DT for all GAs examined. Whilethe conversion of the translocated [3H]GA1 to [3H]GA8 and itsconjugates was rapid in hypocotyl, the conversion of translocated[3H]GA20 to [3H]GA29 was slow. Radioactivity in epicotyls wasdetected much more rapidly on application of [3H]GA20 than of[3H]GA1, [3H]GA8 and [3H]GA29 and their conjugates. The conversionof [3H]GA20 to [3H]GA1 in the epicotyl was more rapid underCL-CL conditions. This result in consistent with the higherlevel of endogenous GA1 existing in epicotyls under CL-DT thanDT-DT conditions. However, when [3H]GA1 was applied to the cotyledon,only small amounts of [3H]GA8 and its conjugates were detectedin the epicotyl regardless of the photoperiodic conditions.This result may suggest that the translocation and metabolismof [3H]GA20 from cotyledons to epicotyl was faster under CL-CLthan DT-DT conditions and may correlate with the increased epicotylelongation of GA20 treated plants under CL-DT than DT-DT conditions. (Received June 28, 1995; Accepted November 2, 1995) 相似文献
93.
Two new loci for hybrid sterility in cultivated rice (Oryza sativa L.) 总被引:17,自引:0,他引:17
J. Wan Y. Yamaguchi H. Kato H. Ikehashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(2):183-190
Female gamete abortion in Indica-Japonica crosses of rice was earlier identified to be due to an allelic interaction at the S-5 locus on chromosome 6. Recently, in other crosses of rice, similar allelic interactions were found at loci designated as S-7 and S-8, located on chromosomes 7 and 6 respectively. All of them are independent of each other. At the S-5 locus, Indica and Japonica rice have S-5
i
and S-5
j
alleles respectively and Javanicas, such as Ketan Nangka, have a neutral allele S-5
n
.The S-5
i
/S-5
j
genotype is semi-sterile due to partial abortion of female gametes carrying S-5
j
, but both the S-5
n
/S-5
i
and S-5
n
/S-5
j
genotypes are fertile. The S-5
n
allele is thus a wide-compatibility gene (WCG), and parents homozygous for this allele are called wide-compatible varieties (WCV). Such parents when crossed with Indica or Japonica varieties do not show F1 hybrid sterility. Wide-compatible parents have been used to overcome sterility barriers in crosses between Indica and Japonica rice. However, a Javanica variety, Ketan Nangka (WCV), showed typical hybrid sterility when crossed to the Indian varieties N22 and Jaya. Further, Dular, another WCV from India, showed typical hybrid sterility when crossed to an IRRI line, IR2061-628-1-6-4-3(IR2061-628). By genetic analyses using isozyme markers, a new locus causing hybrid sterility in crosses between Ketan Nangka and the Indicas was located near isozyme loci Est-1 and Mal-1 on chromosome 4, and was designated as S-9. Another new locus for hybrid sterility in the crosses between Dular and the IR2061-628 was identified and was found linked to four isozyme loci, Sdh-1, Pox-2, Acp-1 and Acp-2, on chromosome 12. It was designated as S-15. On the basis of allelic interactions causing female-gamete abortion, two alleles were found at S-9, S-9
kn
in Ketan Nangka and S-9
i
in N22 and Jaya. In the heterozygote, S-9
kn
/S-9
i
, which was semisterile, female gametes carrying S-9
kn
were aborted. The hybrid of Dular and IR2061-628, with a genetic constitution of S-15
Du
/S-15
i
, was semi-sterile and the female gametes carrying S-15
Du
were aborted. A Japonica tester variety, Akihikari, and an Indica variety, IR36, were found to have neutral alleles, S-9
nand S-15
n, at these loci, in addition to S-7
nand at S-7. The accumulation of three neutral alleles into a breeding line should help solve the hybrid sterility problem in wide crosses of rice. 相似文献
94.
Masayoshi Yamaguchi Reiko Makino Noriaki Shimokawa 《Molecular and cellular biochemistry》1996,165(2):145-150
95.
The effect of -alany-L-histidinato zinc (AHZ) on bone cell function was investigated in osteoblastic MC3T3-E1 cells. Cells were cultured for 3 days at 37°C in a CO2 incubator in plastic dishes containing -modified minimum essential medium supplemented with 10% fetal bovine serum. After the cultures, the medium was exchanged for that containing 0.1% bovine serum albumin plus AHZ (10–7–10–5 M) or other reagents, and the cells were cultured further for appropriate periods of time. The presence of AHZ (10–7–10–5 M) produced a remarkable increase of alkaline phosphatase activity and protein concentration in osteoblastic cells. Thus increases were seen with the prolonged cultivation (12–21 days). With the culture of 1, 3 and 12 days, the effect of AHZ (10–6 M) to increase alkaline phosphatase activity and protein concentration was more intensive than the effect of zinc sulfate, (10–6 M). The AHZ effects were completely abolished by the presence of cycloheximide (10–6 M), indicating that AHZ stimulates protein synthesis in the cells. The present study suggests that AHZ has a stimulatory effect on cell differentiation, and that this effect is partly involved on protein synthesis in osteoblastic cells. 相似文献
96.
Morita Shimpei; Fukase Masami; Hoshino Kumiko; Fukuda Yoichi; Yamaguchi Masami; Morita Yuhei 《Plant & cell physiology》1994,35(7):1049-1056
A proteolytic activity directed against the 相似文献
97.
Thomas Pazdernik Robert Cross Stanley Nelson Yumi Kamijo Fred Samson 《Neurochemical research》1994,19(11):1393-1400
A poorly understood marked decrease (circa 50% of control) in local cerebral glucose utilization is caused by sublethal doses of NaCN. The decrease is global, occurring in essentially all brain regions and is entirely reversible within hours, leaving no obvious pathology. This event is not unique to NaCN in so far as a strikingly similar pattern of decreased glucose utilization occus with some other toxins. Nor can it be attributed to a direct action of NaCN since local application by microdialysis to the striatum produces a global depression. These results imply that some widely distributed system or substance is involved. We speculate the existence of a system possibly related to the reticular activating system that senses a fall in energy production and acts globally to make cells quiescent and thus would give some protection from excitotoxic driven damage.Special issue dedicated to Dr. Sidney Ochs. 相似文献
98.
John G. Frazier Harry L. Fierstine Sallie C. Beavers Federico Achaval Hiroyuki Suganuma Robert L. Pitman Yuichiro Yamaguchi Carlos Ma. Prigioni 《Environmental Biology of Fishes》1994,39(1):85-96
Synopsis Billfishes have long been known to impale a great variety of objects, but there are only two brief, obscure records of marine
turtles being speared. Details are presented on these two, as well as on two other confirmed records; data from two additional
unconfirmed records are also presented. In total, three species of marine turtles are known to have been impaled by three
species of billfishes; a fourth species of fish and a fourth species turtle are listed in an unconfirmed case. Records come
from the eastern and western Pacific as well as the eastern Atlantic. Of the four confirmed cases, the turtles survived in
two, and apparently died as an effect of the spearing in the other two. In three confirmed cases only the impaled rostrum
was encountered, and in one confirmed case the entire fish was found, with its rostrum piercing the turtle. There is no obvious
advantage — or clear disadvantage — involved in impaling turtles. It is argued that these attacks are accidental, and the
result of attempts made by the billfish to capture prey that are near the turtle. These spearings indicate that the chelonians
serve as shelters for prey animals on the high seas, and thus, are further evidence of the pelagic existence of marine turtles.
The impalings are evidence of a singular ecological role of the turtles — as live fish aggregation devices. 相似文献
99.
Tetsuya Matsumoto Mitsuo Kaku Kazuhiro Tateda Nobuhiko Furuya Yoichi Hirakata Keizo Yamaguchi 《Microbiology and immunology》1994,38(4):287-293
We evaluated antibody-coated bacteria (ACB) in expectorated sputum to discriminate contaminating or colonizing organisms from true pathogens. We examined 60 expectorated sputum samples from 51 patients with lower respiratory infections (chronic obstructive pulmonary disease 25, pneumonia 20, purulent tracheobronchitis 6). All samples were examined with quantitative culture and immunofluorescent demonstration of ACB. From the results of quantitative culture, we divided specimens into pathogen-isolated and pathogen-free samples. Among pathogen-isolated samples, in which we isolated accepted pathogenic organisms at ≥ 107 colony-forming units per ml, 16 of 23 samples were ACB-positive (69.5%). In contrast, among pathogen-free samples, in which we isolated accepted pathogens at < 107 colony forming units per ml or only upper respiratory flora, only 3 of 37 samples were ACB-positive (8.1%). The ACB-positive rate was significantly higher in pathogen-isolated than in pathogen-free samples (P < 0.001). Consequently, detecting ACB in expectorated sputum shows good potential as another criterion for distinguishing contaminating or colonizing organisms from true pathogens. 相似文献
100.
Safak Yalcin Hirohiko Kuratsune Koji Yamaguchi Teruo Kitani Koichi Yamanishi 《Microbiology and immunology》1994,38(7):587-590
Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome. 相似文献