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1.
The arrangement of wall microtubules (MTs) in Pisum sativumroots was viewed immunofluorescently using cryosectioning. Mostcells in the tip region of pea roots (02 mm from tip)had wall MTs arranged transversely to the root axis. In theregion elongating at a higher rate (24 mm), wall MTsof epidermal, cortical and stelar cells were all transverselyarranged. In the region of about 5 mm from the tip, in whichcell elongation had already ceased, wall MTs in cortical cellschanged from a transverse to an oblique arrangement in relationto the root axis. Some cells had a crossed arrangement of wallMTs, which was interpreted as representing two sets of unidirectional,oblique wall MTs in opposite cell cortices of a single cell.This change was completed within a region of 1-mm width. Sinceroots elongated at a rate of 0.6 mm h1, it means thatthe arrangement of wall MTs changed within 2 h. An oblique arrangementof wall MTs was also observed in stelar cells. As the cellsaged, the oblique arrangement tended to change to a steeperor even a longitudinal one. (Received January 24, 1986; Accepted May 15, 1986) 相似文献
2.
Cells ofClosterium ehrenbergii expanded for about 4.5 hr after vegetative cell division and about 3 hr after sexual cell division. Short cells were produced by the sexual expansion. At the early stage of the vegetative and the sexual expansion, most microfibrils were deposited transversely to the cell axis on the inner surface of the new wall. Then, bundles of microfibrils, running in various directions, overlaid the transverse microfibrils already deposited, at the late stage of the both types of expansion. The pattern of microfibril deposition changed from the transverse to the bundled pattern about 4 hr after the vegetative and about 2 hr after the sexual cell division, respectively. The change of pattern of microfibril deposition seemed to be highly correlated with cessation of cell expansion. 相似文献
3.
Localization of anchor loci representing five hundred annotated rice genes to wheat chromosomes using PLUG markers 总被引:1,自引:0,他引:1
Goro Ishikawa Toshiki Nakamura Taizo Ashida Mika Saito Shuhei Nasuda Takashi R. Endo Jianzhong Wu Takashi Matsumoto 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(3):499-514
PCR-based Landmark Unique Gene (PLUG) markers are EST-PCR markers developed based on the orthologous gene conservation between
rice and wheat, and on the intron polymorphisms among the three orthologous genes derived from the A, B and D genomes of wheat.
We designed a total of 960 primer sets from wheat ESTs that showed high similarity with 951 single-copy rice genes. When genomic
DNA of Chinese Spring wheat was used as a template, 872 primer sets amplified one to five distinct products. Out of these
872 PLUG markers, 531 were assigned to one or more chromosomes by nullisomic-tetrasomic analysis. For each wheat chromosome,
the number of loci detected ranged from 32 for chromosome 6A to 73 for chromosome 7D, with an average of 48 loci per chromosome.
Several novel synteny perturbations were identified using deletion bin-mapping of markers. Furthermore, we demonstrated that
PLUG markers can be used as probes to simultaneously identify BAC clones that contain homoeologous regions from all three
genomes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss 下载免费PDF全文
Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
5.
Taizo Maeda Hiroshi Abe Kazuo Kakiki Tomomasa Misato 《Bioscience, biotechnology, and biochemistry》2013,77(5):700-709
Studies were conducted on the influence of Kitazin analogues on the incorporation of 14C-glucosamine into the mycelial cell wall fraction of Pyricularia oryzae. Compounds of thiolates and phosphates, both having in vitro inhibitory activities toward the mycelial growth, inhibited the incorporation, whereas those of thionates and dithioates, either having no fungitoxicity, did not inhibit the incorporation. Mycelia of P. oryzae treated with Kitazin-P (S-benzyl O,O′-diisopropyl phosphrothioate; IBP) accumulated about twice as much an amino sugar derivative as untreated ones. Mycelia treated with thiono or dithio analogues, which have no fungitoxicity, showed no accumulation. The accumulated substance gave a identical spot with authentic UDP-N-acetyl glucosamine on paper chromatograms developed with four solvent systems. 相似文献
6.
7.
Early Abortive Lysis by Phage BF23 in Escherichia coli K-12 Carrying the Colicin Ib Factor 总被引:8,自引:8,他引:8 下载免费PDF全文
Growth of phage BF23 was restricted in Escherichia coli K-12 strains carrying a colicin I factor (ColIb); most infected cells lysed early without producing progeny phages. Either addition of chloramphenicol before phage infection or ultraviolet irradiation of phage prevented early abortive lysis, an indication that certain phage functions are required for this phenomenon. Very little or no phage-induced lysozyme was synthesized in the infected ColI(+) cells. This result suggests that early abortive lysis was not due to the lysozyme action. A small fraction (0.05) of BF23-infected ColI(+) cells showed normal phage growth. This "escaped growth" may reflect the physiological state of the host bacteria rather than the heterogeneity of the infecting phage. Host-controlled modification was not observed. A phage mutant, BF23hI, able to grow on ColI(+) cells, was isolated and was characterized to be recessive to the wild-type BF23 in its ability to undergo early abortive lysis. Among the T series phages, T5 induced early abortive lysis, and growth of T5 was restricted upon infection to ColI(+) cells. These results and the other observations, including the occurrence of phenotypic mixing between BF23 and T5, suggest that these two phages are related to each other even though the receptor sites for BF23 and T5 are apparently different. 相似文献
8.
Difference between effects of sulfur dioxide (SO2) and ozone (O3) on groundnut plants (Arachis hypogaea L.) was studied by use of an exposure system of enzymatically-isolated mesophyll cells. SO2 inhibited photosynthesis of intact groundnut leaves but induced no visible injury on leaves. SO2 also inhibited photosynthesis of isolated mesophyll cells but did not kill the cells, suggesting that SO2 inhibits photosynthesis by attacking rather specifically the photosynthetic apparatus in chloroplasts. O3 inhibited photosynthesis of intact leaves and at the same time induced visible injury corresponding to the extent of photosynthesis
inhibition. O3 also inhibited photosynthesis of isolated mesophyll cells and killed the cells to the extent corresponding to photosynthesis
inhibition, suggesting that O3 inhibits photosynthesis not directly by attacking the photosynthetic apparatus but indirectly by killing cells. Since the
response of intact leaves to each pollutant resembled that of isolated mesophyll cells, the difference between responses of
intact leaves to both pollutants may considerably reflect that of mesophyll cells. 相似文献
9.
T. Togashi Taizo Motomura Terunobu Ichimura Paul Alan Cox 《Sexual plant reproduction》1999,12(3):158-163
The role of phototactic behavior of gametes was tested experimentally in the slightly anisogamous marine green alga Monostroma angicava Kjellman, and the effect of phototaxis on mating efficiency was discovered. Both male and female gametes showed positive
phototaxis in response to a white light source. In contrast, they did not respond to a red light source. Their swimming velocity
did not differ between these two illuminating light sources. It was, therefore, suggested that the search ability of the gamete
itself might not vary between phototactic and non-phototactic conditions. The number of zygotes formed during the mating process
may be expressed as the product of the number of encounters between male and female gametes and the fraction of encounters
that result in sexual fusion. In this study, with high densities of male and female gametes mixed in test tubes, almost all
minor (fewer in number) gametes fused sexually within 10 min. After dilution of the gamete suspensions by half, mating efficiency
in test tubes illuminated by white light from above was higher than that in dark controls. This suggests that male and female
gametes gathered at the water surface through their positive phototaxis, thus increasing the rate of encounters. Mating efficiency
also decreased if the test tubes were illuminated from above by white light and also shaken. Since negative phototaxis is
clearly shown in planozygotes, we suggest that positive phototaxis of male and female gametes in M. angicava is an adaptive trait for increasing the rate of gametic encounters rather than for the dispersal of zygotes as previously
reported for zoospores of some marine algae.
Received: 12 February 1999 / Revision accepted: 24 May 1999 相似文献
10.
In azuki bean (Azukia angularis = Vignia angularis) epicotylsections, 5 ? 104 M coumarin inhibited the incorporationof radioactivity from [U14C]glucose into the cellulosefraction by 35% in the absence of indole-3-acetic acid (IAA)and by 40% in the presence of 1 ? 104 M IAA. There wasno inhibitory effect on the incorporation of radioactivity intothe other fractions. Coumarin at 5 ? 104 M reversed thepromoting effect of 1 ? 105 M gibberellin A3 (GA) andthe inhibitory effect of 1 ? 105 M kinetin on IAA-inducedelongation of sections with no significant effects on IAA-inducedelongation. Neither GA nor kinetin had any appreciable effectson cellulose synthesis. No inhibition of cellulose syntheiswas observed with 1 ? 103 M colchichine, which has beenreported to have effects similar to those of coumarin on GA-or kinetin-affected stem elongation. Coumarin at 5 ? 104M was ineffectual in breaking up wall microtubules, while adisrupting effect on wall microtubules was clearly demonstratedwith 3 ? 104M colchicine. From these results, the possible involvement of cellulose synthesisin cell expansion controlled by GA or kinetin was suggested. (Received August 3, 1973; ) 相似文献