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41.
Monotherapy with a novel intervenolin derivative,AS‐1934, is an effective treatment for Helicobacter pylori infection 下载免费PDF全文
42.
Hayashi Takahisa; Takeda Takumi; Ogawa Kozo; Mitsuishi Yasushi 《Plant & cell physiology》1994,35(6):893-899
Xyloglucan oligosaccharides were isolated with various degreesof polymerization (DP) and reduced with tritiated sodium borohydride.The 3H-oligosaccharides were tested for their ability to bindto amorphous and microcrystalline celluloses and to cellulosefilter paper. The time course of binding indicated that theradiolabeled oligosaccharides continued to be bound for at least1 h after heating at 120°C. The binding probably requiredthe organization of the oligosaccharides and celluloses by gradualannealing after heating. Although neither pentasaccharide (glucose:xylose, 3 : 2), heptasaccharide (glucose: xylose, 4 : 3) andnonasaccharide (glucose : xylose : galactose : fucose, 4 : 3: 1 : 1) failed to bind to the celluloses, binding occurredwith oligosaccharides with DP equivalent to more than four consecutive1,4-ß-glucosyl residues. The extent of binding tothe celluloses increased gradually from octasaccharide (glucose:xylose, 5 : 3) to hendecosanosaccharide (glucose/xylose, 12: 9), with the increase in the DP of 1,4-ß-glucosylresidues. The binding of reduced cello-dextrins to celluloserequired at least 4 consecutive 1,4-ß-glucosyl residues.The extent of binding of cellopentitol or cellohexitol to cellulosewas similar to that of hendecosanosaccharide, showing lowerbinding for xyloglucan oligosaccharides in spite of longer chainsof 1,4-ß-glucosyl residues. These findings suggestthat the mode of binding to cellulose of xyloglucan oligosaccharidesis different from that of cello-oligosaccharides. (Received February 18, 1994; Accepted June 1, 1994) 相似文献
43.
Plants have evolved various means for controlled and organized cell destruction, known as programmed cell death (PCD). In
plant immune responses against microbial infection, hypersensitive cell death as a form of PCD is a crucial event to prevent
the spread of biotrophic pathogens. Recent live cell imaging techniques have revealed dynamic features and significant roles
of cytoskeletons and the vacuole during defense responses and the PCD. Actin microfilaments (MFs) focus on the infection sites
and function as tracks for the polar transport of antimicrobial materials. To accomplish hypersensitive cell death, further
dynamic changes in cytoskeletons are induced. MFs play a role in the structural and functional regulation of the vacuole,
leading to execution of the PCD. We here overview spatiotemporal dynamic changes in the cytoskeletons and the vacuoles triggered
by signals from pathogens, and propose a hypothetical model for MF-regulated vacuole-mediated PCD in plant immunity. 相似文献
44.
Noguchi Takumi; Kamimura Yasumaro; Inoue Yorinao; Itoh Shigeru 《Plant & cell physiology》1999,40(3):305-310
A water-soluble Chl a/b-protein complex, CP668, from Chenopodiumalbum converts to another form of protein complex, CP743, uponlight illumination. Structural changes of pigments and proteinsupon photoconversion were studied using resonance Raman (RR)and Fourier transform infrared (FTIR) spectroscopies. RR spectraof CP668 and CP743 and a light-induced FTIR difference spectrumshowed that the macrocyle C=C bands of Chl a in CP668 considerablychanged upon conversion to the pigment (not chemically identifiedyet) in CP743. The C=C band pattern of the RR spectrum of CP743was similar to that of bacteriochlorophyll a, suggesting thatthe conjugated system of the CP743 pigment resembles a bacteriochlorinring. Judging from the C=O frequencies, the 131-keto C=O groupsof Chl a and b in CP668 are free from hydrogen bonding, whereasthe 132-ester C=O groups of both Chl a and b and the 7-formylC=O of Chl b in CP668 are hydrogen bonded. Upon conversion toCP743, interactions of the 131-keto and 132-ester C=O groupswere basically unaffected, demonstrating no drastic changesaround these C=O groups. FTIR spectra in the amide I' regionof CP668 and CP743 in D2O buffer showed a peak at 1,633 cm1,which represents a major component of ß-sheet conformation.Second-derivative spectra of the amide I' bands as well as alight-induced FTIR difference spectrum suggested that drasticchange in the protein conformation does not occur upon photoconversion. (Received November 1, 1998; Accepted December 24, 1998) 相似文献
45.
46.
Wei T Miyazaki N Uehara-Ichiki T Hibino H Shimizu T Netsu O Kikuchi A Sasaya T Iwasaki K Omura T 《Journal of molecular biology》2011,410(3):436-446
Examination of cultured insect vector cells that had been infected with Rice gall dwarf virus (RGDV), using transmission electron microscopy and confocal microscopy, revealed the presence of clusters of virus-coated mitochondria around viroplasms in which replication and assembly of RGDV occurred, suggesting a role for mitochondria in supplying the energy required for viral morphogenetic processes. Electron tomography revealed that RGDV particles on the surface of mitochondria are arrayed in an orderly but loose manner, unlike tightly packaged particles in vesicular compartments, suggesting the presence of counterpart molecules on the surface of mitochondria. The viral particles in close proximity to mitochondria were aligned along intermediate filaments, which might serve as scaffolds for the anchorage of these particles. RGDV has a putative mitochondrion-targeting sequence on the outer surface of the outer-capsid protein P8. The arrangement of RGDV particles around mitochondria suggests that the region of the P8 protein containing the mitochondrion-targeting sequence might attach to a molecule like a receptor on the outer mitochondrial membrane. Our analysis demonstrates the three-dimensional arrangement and molecular basis for the mitochondrial proximity of RGDV particles during viral replication. 相似文献
47.
Takashi Tanaka Keiko Kawamura Takumi Kitahara Hiroshi Kohda Osamu Tanaka 《Phytochemistry》1984,23(3):615-621
Previously, a sweet steviol bisglucoside named rubusoside was isolated from leaves of a Chinese Rubus spp. which was tentatively assigned as R. chingii. From leaves of Japanese Rubus chingii (Japanese name Gosho-Ichigo) which are not sweet, five ent-labdane-type diterpene glucosides named goshonosidies F1-5 were isolated instead of rubusoside and their structures were elucidated. The name ‘R. suavissimus’ has been proposed for the Chinese plant. 相似文献
48.
49.
Akihito Tanaka Knut Woltjen Katsuya Miyake Akitsu Hotta Makoto Ikeya Takuya Yamamoto Tokiko Nishino Emi Shoji Atsuko Sehara-Fujisawa Yasuko Manabe Nobuharu Fujii Kazunori Hanaoka Takumi Era Satoshi Yamashita Ken-ichi Isobe En Kimura Hidetoshi Sakurai 《PloS one》2013,8(4)
The establishment of human induced pluripotent stem cells (hiPSCs) has enabled the production of in vitro, patient-specific cell models of human disease. In vitro recreation of disease pathology from patient-derived hiPSCs depends on efficient differentiation protocols producing relevant adult cell types. However, myogenic differentiation of hiPSCs has faced obstacles, namely, low efficiency and/or poor reproducibility. Here, we report the rapid, efficient, and reproducible differentiation of hiPSCs into mature myocytes. We demonstrated that inducible expression of myogenic differentiation1 (MYOD1) in immature hiPSCs for at least 5 days drives cells along the myogenic lineage, with efficiencies reaching 70–90%. Myogenic differentiation driven by MYOD1 occurred even in immature, almost completely undifferentiated hiPSCs, without mesodermal transition. Myocytes induced in this manner reach maturity within 2 weeks of differentiation as assessed by marker gene expression and functional properties, including in vitro and in vivo cell fusion and twitching in response to electrical stimulation. Miyoshi Myopathy (MM) is a congenital distal myopathy caused by defective muscle membrane repair due to mutations in DYSFERLIN. Using our induced differentiation technique, we successfully recreated the pathological condition of MM in vitro, demonstrating defective membrane repair in hiPSC-derived myotubes from an MM patient and phenotypic rescue by expression of full-length DYSFERLIN (DYSF). These findings not only facilitate the pathological investigation of MM, but could potentially be applied in modeling of other human muscular diseases by using patient-derived hiPSCs. 相似文献
50.