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81.
Haruhiko Washida Aya Sugino Sachiyo Kaneko Naoko Crofts Chotipa Sakulsingharoj Dongwook Kim Sang-Bong Choi Shigeki Hamada Masahiro Ogawa Changlin Wang Asim Esen Thomas J.V. Higgins Thomas W. Okita 《The Plant journal : for cell and molecular biology》2009,60(1):146-155
The RNAs for the storage proteins of rice ( Oryza sativa ), prolamines and glutelins, which are stored as inclusions in the lumen of the endoplasmic reticulum (ER) and storage vacuoles, respectively, are targeted by specific cis -localization elements to distinct subdomains of the cortical ER. Glutelin RNA has one or more cis -localization elements (zip codes) at the 3' end of the RNA, whereas prolamine has two cis -elements; one located in the 5' end of the coding sequence and a second residing in the 3'-untranslated region (UTR). We had earlier demonstrated that the RNAs for the maize zeins ('prolamine' class) are localized to the spherical protein body ER (PB-ER) in developing maize endosperm. As the PB-ER localization of the 10-kDa δ-zein RNA is maintained in developing rice seeds, we determined the number and proximate location of their cis -localization elements by expressing GFP fusions containing various zein RNA sequences in transgenic rice and analyzing their spatial distribution on the cortical ER by in situ RT-PCR and confocal microscopy. Four putative cis -localization elements were identified; three in the coding sequences and one in the 3'-UTR. Two of these zip codes are required for restricted localization to the PB-ER. Using RNA targeting determinants we show, by mis-targeting the storage protein RNAs from their normal destination on the cortical ER, that the coded proteins are redirected from their normal site of deposition. Targeting of RNA to distinct cortical ER subdomains may be the underlying basis for the variable use of the ER lumen or storage vacuole as the final storage deposition site of storage proteins among flowering plant species. 相似文献
82.
The antimicrobial action of acriflavine, a quaternary ammonium compound, on Staphylococcus aureus was studied by electron microscopic observation. The bactericidal activity of acriflavine was dose-dependent over the 4 hr of exposure time. Scanning electron micrographs showed a wavy wrinkled cell surface following treatment with acriflavine. Transmission electron micrographs showed thickened cell walls following treatment with acriflavine. Acriflavine-induced cell wall thickness seemed to affect both the peripheral and cross walls, but was reversible after treatment removal. These findings indicate that cell wall thickness is a characteristic phenotype of S. aureus exposed to acriflavine. It is therefore believed that cell wall thickness plays an important role in the mechanism of action of acriflavine. 相似文献
83.
The application of the mutated acetolactate synthase gene from rice as the selectable marker gene in the production of transgenic soybeans 总被引:1,自引:0,他引:1
Makoto Tougou Noriko Yamagishi Noriyuki Furutani Koichiro Kaku Tsutomu Shimizu Yoshihito Takahata Jun-ichi Sakai Seiji Kanematsu Soh Hidaka 《Plant cell reports》2009,28(5):769-776
We investigated selective culturing conditions for the production of transgenic soybeans. In this culturing system, we used
the acetolactate synthase (ALS)-inhibiting herbicide-resistance gene derived from rice (Os-mALS gene) as a selectable marker gene instead of that derived from bacteria, which interfered with the cultivation and practical
usage of transgenic crops. T1 soybeans grown from one regenerated plant after selection of the ALS-targeting pyrimidinyl carboxy (PC) herbicide bispyribac-sodium
(BS) exhibited herbicide resistance, and the introduction and expression of the Os-mALS gene were confirmed by genetic analysis. The selective culturing system promoted by BS herbicide, in which the Os-mALS gene was used as a selectable marker, was proved to be applicable to the production of transgenic soybeans, despite the appearance
of escaped soybean plants that did not contain the Os-mALS transgene. 相似文献
84.
Mio Nakamura Koji Nomura Jun-ichi P. Abe Yousuke Degawa Makoto Kakishima 《Mycoscience》2009,50(6):448-451
A simple method for isolating the nuclei from Basidiobolus ranarum was established. To improve the yield and purity of nuclei, we investigated maceration methods, buffer composition, and centrifugation
conditions to establish an optimal procedure. Basidiobolus ranarum cultured for 5 days was enzymatically macerated and then homogenized and filtrated through stainless steel sieves. The crude
cell homogenate was loaded on a layer of buffer containing 50% glycerol and centrifuged at 1500 g. The resultant pellet contained pure nuclei. 相似文献
85.
86.
Shigeaki Ito Shigeki Hamada Hiroyuki Ito Hirokazu Matsui Tadahiro Ozawa Hidenori Taguchi Susumu Ito 《Biotechnology letters》2009,31(7):1065-1071
The cellobiose 2-epimerase from Ruminococcus albus (RaCE) catalyzes the epimerization of cellobiose and lactose to 4-O-β-d-glucopyranosyl-d-mannose and 4-O-β-d-galactopyranosyl-d-mannose (epilactose). Based on the sequence alignment with N-acetyl-d-glucosamine 2-epimerases of known structure and on a homology-modeled structure of RaCE, we performed site-directed mutagenesis
of possible catalytic residues in the enzyme, and the mutants were expressed in Escherichia coli cells. We found that R52, H243, E246, W249, W304, E308, and H374 were absolutely required for the activity of RaCE. F114
and W303 also contributed to catalysis. These residues protruded into the active-site cleft in the model (α/α)6 core barrel structure. 相似文献
87.
Abstract. We investigated the seasonal prevalence of reproductive activities and of the development of brooded propagules in an intertidal sea anemone, Anthopleura sp., on the rocky shore of Mutsu Bay, in northern Japan. A monthly examination of anemones, by dissection and histological techniques, revealed no sign of gonad development, but did reveal that they produce and internally brood propagules throughout the year. Release of propagules was observed in the field. This anemone population appears to be entirely asexual and agametic, and may persist solely through clonal propagation. 相似文献
88.
Phylogeny and distribution of extra-slow-growing Bradyrhizobium japonicum harboring high copy numbers of RSα, RSβ and IS1631 总被引:1,自引:0,他引:1
89.
The pineal hormone melatonin (N-acetyl-5-methoxytryptamine) exerts antigonadotropic effects in some mammalian species. To evaluate the effect of luteinizing hormone (LH) on melatonin release and its synthesizing enzyme activities in pineal glands, pineals of adult female rats undergoing diestrus were organ-cultured in a medium containing 10(-12), 10(-10) or 10(-8) M LH for 6 h. Melatonin release increased significantly in pineals cultured with 10(-12) and 10(-10) M LH, as compared to control values. Similarly, the activity of arylalkylamine N-acetyltransferase (NAT), the key regulatory enzyme in melatonin biosynthesis, was significantly higher in pineals cultured with 10(-12) and 10(-10) M LH for 6 h, while LH at 10(-8) M had no effect. Although LH at 10(-10) M increased pineal hydroxyindole-O-methyltransferase (HIOMT) activity, which catalyzes the final step of melatonin biosynthesis, LH at 10(-12) and 10(-8) M had no effect. These results demonstrate that at relatively low physiological levels, LH stimulates pineal melatonin synthesis and release, mainly by increasing NAT activity. 相似文献