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161.
Daisuke Fujita Leodegario A. Ebron Etsuko Araki Hiroshi Kato Gurdev S. Khush John E. Sheehy Tanguy Lafarge Yoshimichi Fukuta Nobuya Kobayashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(6):1233-1240
Tillering is one of the most important agronomic traits related to grain production in rice (Oryza sativa L.). A japonica-type variety, Aikawa 1, is known to have low-tiller number. The detailed location of a low-tillering gene,
Ltn, which has been localized on chromosome 8 in Aikawa 1, was confirmed by molecular mapping. Using BC5F2 individuals derived from a cross between IR64 and Aikawa 1, the low-tillering gene was mapped to an interval defined by SSR
markers ssr5816-3 and A4765. This was designated as Ltn because there was no reported gene for tillering in the region of chromosome 8. Through high-resolution linkage analysis,
the candidate region of Ltn was located between DNA markers ssr6049-23 and ind6049-1 corresponding to 38.6 kbp on the Nipponbare genome sequence. These DNA markers, which were tightly linked to Ltn, are useful for marker-assisted selection in breeding studies. 相似文献
162.
Assiminea affinis (Mousson ms) Böttger, 1887(=A. queenslandica [Pilsbry ms] Thiele, 1927), a previously unrecognised Australian assimineid species, is described anatomically and allocated to the genus Taiwanassiminea Kuroda and Habe, 1950, first described from Taiwan. This is the first record of the genus from Australia. Taiwanassiminea affinis is found in slightly brackish waters in the upper tidal reaches of the larger rivers from northern Queensland to the Shoalhaven River in the southern half of New South Wales. The terrestrial Cyclotropis Tapparone-Canefri, 1883, which has somewhat similar shell and radular characters, is redefined and several species (Assiminea bedaliensis Rensch, 1934; Paludinella javana Thiele, 1927; Assiminea lentula, A. riparia and A. sororcula, all Benthem Jutting, 1963) previously included in Cyclotropis are transferred to Taiwanassiminea. 相似文献
163.
Takei Y Kadomatsu K Itoh H Sato W Nakazawa K Kubota S Muramatsu T 《The Journal of biological chemistry》2002,277(26):23800-23806
Oligodeoxynucleotides modified at both 5'- and 3'-ends with inverted thymidine (5'-,3'-inverted T) were introduced as new reagents for antisense strategies. These modifications were performed to make the oligodeoxynucleotides resistant to nucleases. The effectiveness of these oligodeoxynucleotides was evaluated in terms of inhibition of synthesis of midkine (MK), a heparin-binding growth factor, and consequent inhibition of growth of CMT-93 mouse rectal carcinoma cells. 5'-,3'-Inverted T antisense MK suppressed synthesis of MK by CMT-93 cells and their growth in culture. Furthermore, 5'-,3'-inverted T oligodeoxynucleotides exhibited less cytotoxicity and better stability than phosphorothioate oligodeoxynucleotides. When 5'-,3'-inverted T antisense MK was mixed with atelocollagen, and injected into CMT-93 tumors pregrown in nude mice, tumor growth was markedly suppressed as compared with tumors injected with sense controls. The suppressive effect of 5'-,3'-inverted T antisense MK on tumor growth was stronger than that of phosphorothioate antisense MK. These findings indicated the usefulness of inverted thymidine-modified antisense oligodeoxynucleotides as a new reagent instead of phosphorothioate-modified oligodeoxynucleotides. 相似文献
164.
Tomohiro Asai Takuma Tsuzuku Shoya Takahashi Ayaka Okamoto Takehisa Dewa Mamoru Nango Kenji Hyodo Hiroshi Ishihara Hiroshi Kikuchi Naoto Oku 《Biochemical and biophysical research communications》2014
Lipid nanoparticles (LNP) modified with cell-penetrating peptides (CPP) were prepared for the delivery of small interfering RNA (siRNA) into cells. Lipid derivatives of CPP derived from protamine were newly synthesized and used to prepare CPP-decorated LNP (CPP-LNP). Encapsulation of siRNA into CPP-LNP improved the stability of the siRNA in serum. Fluorescence-labeled siRNA formulated in CPP-LNP was efficiently internalized into B16F10 murine melanoma cells in a time-dependent manner, although that in LNP without CPP was hardly internalized into these cells. In cells transfected with siRNA in CPP-LNP, most of the siRNA was distributed in the cytoplasm of these cells and did not localize in the lysosomes. Analysis of the endocytotic pathway indicated that CPP-LNP were mainly internalized via macropinocytosis and heparan sulfate-mediated endocytosis. CPP-LNP encapsulating siRNA effectively induced RNA interference-mediated silencing of reporter genes in B16F10 cells expressing luciferase and in HT1080 human fibrosarcoma cells expressing enhanced green fluorescent protein. These data suggest that modification of LNP with the protamine-derived CPP was effective to facilitate internalization of siRNA in the cytoplasm and thereby to enhance gene silencing. 相似文献
165.
Histone dynamics in living cells revealed by photobleaching 总被引:5,自引:0,他引:5
Kimura H 《DNA Repair》2005,4(8):939-950
166.
The ultrastructure of the purified and lyophilized endotoxin from Escherichia coli O111 was observed by ultrathin sectioning. Onion-like globular membrane structures were observed in addition to rod-like and ribbon-like structures, indicating the existence of a globular membrane structure even in the dried state. 相似文献
167.
168.
Cationic liposome-mediated gene delivery: biophysical study and mechanism of internalization 总被引:12,自引:0,他引:12
Almofti MR Harashima H Shinohara Y Almofti A Baba Y Kiwada H 《Archives of biochemistry and biophysics》2003,410(2):246-253
To identify factors affecting cationic liposome-mediated gene delivery efficiency, we studied the relationship between the biophysical characteristics of liposome/DNA complexes (lipoplexes) at different (+/-) charge ratios, their structures as monitored by atomic force microscopy (AFM), and their mechanism(s) of internalization into the cells. Significant changes were observed in the particle size and zeta potential of liposomes and their structures assessed by AFM upon addition of DNA, which depended on (+/-) charge ratios. AFM images showed that lipoplexes were formed from extensively fused and apparently homogeneous lipid particles encapsulating DNA. Lipoplexes were found to internalize the cells through the endocytosis pathway. Lipoplex-cell fusion was found to occur mainly at the plasma membrane level; however, this lipoplex-cell membrane fusion was found to be essential for the uptake of the large particles. A new perspective for the internalization of large lipoplex particles into cytoplasm is discussed. 相似文献
169.
170.