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1.
Formation of a Tree having a Low Lignin Content 总被引:2,自引:0,他引:2
Received 30 September 2001/ Accepted in revised form 26 October 2001 相似文献
2.
Kenji Tomioka Kenji Yamada Shinya Yokoyama Yoshihiko Chiba 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(3):291-298
The coupling mechanism between the bilaterally paired optic lobe circadian pacemakers in the cricket Gryllus bimaculatus was investigated by recording locomotor activity, under constant light or constant red light, after the optic nerve was unilaterally severed.
These results suggest that the 2 optic lobe pacemakers weakly couple to one another and that the cricket maintains a stable temporal structure in its behavior through the phase-dependent mututal inhibition of activity and the phase-dependent freerunning period modulation. 相似文献
1. | The majority (about 70%) of the animals showed a locomotor rhythm with 2 rhythmic components; one freerunning with a period of 25.33 ± 0.41 (SD) h and the other with 24.36 ± 0.37 (SD) h under constant light (Fig. 3A). |
2. | Removal of the intact side optic lobe abolished the longer period component (Fig. 4A), while the operation on the operated side caused a reverse effect (Fig. 4B), indicating that the longer and the shorter period components are driven by the pacemaker on the intact and the operated side, respectively. |
3. | The activity driven by a pacemaker was inhibited during the subjective day of the contralateral pacemaker (circadian time 0–10, Fig. 5). |
4. | The freerunning periods of the two components were not constant but varied as a function of the mutual phase angle relationship (Figs. 3A, 7, 8). |
3.
Kimio Fukami Shinya Nishimura Masamichi Ogusa Miki Asada Toshitaka Nishijima 《Hydrobiologia》1997,358(1-3):245-249
A continuous culture system for a benthic food diatom Nitzschia sp. wasestablished by using properties of high nutrient and clean of deep seawater(DSW). DSW collected from 320 m depth in Muroto City, Japan, was introducedinto a glass-pipe bioreactor (14 cm length, 3 cm diam.) containing glassbeads of 0.5 cm diam. as substrata for the alga, and it was incubated at18°C · 80Em–2sec–1 · L:D=14:10. The chlorophyll a yield of benthicdiatoms in a reactor as a unit of surface area of the substratum was only0.001–0.003 g cm–2 when the flow rate of DSW was 0(batch culture conditions). However, when DSW was supplied continuously to areactor, the yield increased to 1.4 g-chl.a cm–2 alongwith the increase in flow rate of DSW. Moreover, amounts of chl.a washed outof the system were negligible, 0.0014 to 0.0045%, even though theflow rate of DSW was as much as 25 times h–1, suggesting thatsloughing of benthic diatoms from the substratum was minimized. Although theyield of diatoms fluctuated significantly at the time that the DSW wascollected, the variation could be minimized by increasing the flow rate ofDSW. These results indicate that the continuous culturing system with DSWsupports the stable and effective mass culture of benthic food diatom. 相似文献
4.
Shinya Nomoto Michiaki Takasaki Hiroshi Naraoka Kaoru Harada 《Origins of life and evolution of the biosphere》1984,14(1-4):123-130
Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere. 相似文献
5.
Noriyuki Nakayama Issay Narumi Shinya Nakamoto Hiroshi Kihara 《Biotechnology letters》1992,14(8):649-652
Summary A new shuttle vector was constructed by inserting a 3.1 kbp-DNA fragment from thermophilicBacillus sp. plasmid pIH41 intoEscherichia coli plasmid pUC18. The resultant hybrid replicates in bothE. coli andB. stearothermophilus. This vector has ten unique restriction sites within a part oflacZ gene. Insertion of foreign DNA into these sites can be readily detected by a coloration method. 相似文献
6.
Growth of the hydrocarbon-rich microalga Botryococcus braunii in secondarily treated sewage 总被引:6,自引:0,他引:6
Shigeki Sawayama Tomoaki Minowa Yutaka Dote Shinya Yokoyama 《Applied microbiology and biotechnology》1992,38(1):135-138
Summary A hydrocarbon-rich green microalga, Botryococcus braunii, was able to grow well in secondarily treated sewage (STS) from domestic waste-water in a batch system. The growth in STS from domestic waste-water was as good as in the common artificial medium of modified Chu 13 and its hydrocarbon contents were high enough at 53% and 40% compared with 58% in the case of the modified Chu 13 medium. B. braunii utilized nitrate from 7.67 or 4.48 mg/l to a level below detection of < 0.01 mg/l in STS. After this consumption of nitrate, nitrite was consumed, and ammonium was not. Phosphate, even at an extremely low concentration, was also consumed by B. braunii. These results show the possibility of using STS as a medium to grow B. braunii and for removal of nitrogen and phosphorus by algal consumption in STS.Correspondence to: S. Yokoyama 相似文献
7.
A system suitable for ultraviolet imaging densitometry of two-dimensional electrophoretic gels that are unstained is described, together with its applications. A flying-spot densitometer linked with a personal computer was used for data acquisition, generation of mapping data, and image processing. Randomly distributed zones of proteins on two-dimensional gels were detected at 280 nm without being stained by two-dimensional scanning, and the densitometric value of each pixel (0.2 x 0.2 mm) was memorized by the computer, which generated a mapping pattern with density contours. The amount and densitometric value of cytochrome c had a linear relationship in the range of 2-200 micrograms. Zone locations of bovine liver proteins separated on two-dimensional gels were indicated on a map expressed in X-Y coordinates, and the pIs and molecular weights could be calculated from the map by use of pI and molecular weight markers on the same gel. 相似文献
8.
Downregulation of p‐COUMAROYL ESTER 3‐HYDROXYLASE in rice leads to altered cell wall structures and improves biomass saccharification 下载免费PDF全文
Yuri Takeda Yuki Tobimatsu Steven D. Karlen Taichi Koshiba Shiro Suzuki Masaomi Yamamura Shinya Murakami Mai Mukai Takefumi Hattori Keishi Osakabe John Ralph Masahiro Sakamoto Toshiaki Umezawa 《The Plant journal : for cell and molecular biology》2018,95(5):796-811
p‐Coumaroyl ester 3‐hydroxylase (C3′H) is a key enzyme involved in the biosynthesis of lignin, a phenylpropanoid polymer that is the major constituent of secondary cell walls in vascular plants. Although the crucial role of C3′H in lignification and its manipulation to upgrade lignocellulose have been investigated in eudicots, limited information is available in monocotyledonous grass species, despite their potential as biomass feedstocks. Here we address the pronounced impacts of C3′H deficiency on the structure and properties of grass cell walls. C3′H‐knockdown lines generated via RNA interference (RNAi)‐mediated gene silencing, with about 0.5% of the residual expression levels, reached maturity and set seeds. In contrast, C3′H‐knockout rice mutants generated via CRISPR/Cas9‐mediated mutagenesis were severely dwarfed and sterile. Cell wall analysis of the mature C3′H‐knockdown RNAi lines revealed that their lignins were largely enriched in p‐hydroxyphenyl (H) units while being substantially reduced in the normally dominant guaiacyl (G) and syringyl (S) units. Interestingly, however, the enrichment of H units was limited to within the non‐acylated lignin units, with grass‐specific γ‐p‐coumaroylated lignin units remaining apparently unchanged. Suppression of C3′H also resulted in relative augmentation in tricin residues in lignin as well as a substantial reduction in wall cross‐linking ferulates. Collectively, our data demonstrate that C3′H expression is an important determinant not only of lignin content and composition but also of the degree of cell wall cross‐linking. We also demonstrated that C3′H‐suppressed rice displays enhanced biomass saccharification. 相似文献
9.
Vasculogenesis, the in-situ assembly of angioblast or endothelial progenitor cells (EPCs), may persist into adult life, contributing to new blood vessel formation. However, EPCs are scattered throughout newly developed blood vessels and cannot be solely responsible for vascularization. Here, we identify an endothelial progenitor/stem-like population located at the inner surface of preexisting blood vessels using the Hoechst method in which stem cell populations are identified as side populations. This population is dormant in the steady state but possesses colony-forming ability, produces large numbers of endothelial cells (ECs) and when transplanted into ischaemic lesions, restores blood flow completely and reconstitutes de-novo long-term surviving blood vessels. Moreover, although surface markers of this population are very similar to conventional ECs, and they reside in the capillary endothelium sub-population, the gene expression profile is completely different. Our results suggest that this heterogeneity of stem-like ECs will lead to the identification of new targets for vascular regeneration therapy. 相似文献
10.
Ren Shimamoto Naoki Amano Tomoko Ichisaka Akira Watanabe Shinya Yamanaka Keisuke Okita 《PloS one》2014,9(4)
It has been shown that DNA demethylation plays a pivotal role in the generation of induced pluripotent stem (iPS) cells. However, the underlying mechanism of this action is still unclear. Previous reports indicated that activation-induced cytidine deaminase (Aid, also known as Aicda) is involved in DNA demethylation in several developmental processes, as well as cell fusion-mediated reprogramming. Based on these reports, we hypothesized that Aid may be involved in the DNA demethylation that occurs during the generation of iPS cells. In this study, we examined the function of Aid in iPS cell generation using Aid knockout (Aid−/−) mice expressing a GFP reporter under the control of a pluripotent stem cell marker, Nanog. By introducing Oct3/4, Sox2, Klf4 and c-Myc, Nanog-GFP-positive iPS cells could be generated from the fibroblasts and primary B cells of Aid−/− mice. Their induction efficiency was similar to that of wild-type (Aid+/+) iPS cells. The Aid−/− iPS cells showed normal proliferation and gave rise to chimeras, indicating their capacity for self-renewal and pluripotency. A comprehensive DNA methylation analysis showed only a few differences between Aid+/+ and Aid−/− iPS cells. These data suggest that Aid does not have crucial functions in DNA demethylation during iPS cell generation. 相似文献