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831.
Protoplasts prepared from an embryogenic cell suspension culture of fennel gave rise to somatic embryoids directly through unequal cell divisions of enlarged, ellipsoidal cells, when embedded in hormone-free LS agarose medium. On the other hand, protoplasts embedded in LS agarose medium containing 2,4-D and kinetin proliferated through unpolarized cell divisions to form calli, which gave somatic embryoids on the surface upon transfer onto the same medium. In either case, somatic embryoids germinated to develop into normal plantlets when cultured on hormone-free LS agar medium under illumination. 相似文献
832.
Jun Hai Kunitoshi Uchida Shotaro Nishimura Shoji Tabata 《Bioscience, biotechnology, and biochemistry》2020,84(10):2121-2127
ABSTRACT Transient receptor potential vanilloid 1 (TRPV1), a nociceptive cation channel, is known to play roles in regulating the energy metabolism (EM) of the whole body. We previously reported that TRPV1 antagonists such as AMG517 enhanced EM in mice, however, these mechanisms remain unclear. The aim of this study was to explore the mechanisms underlying the enhancement of EM by AMG517, a selective TRPV1 antagonist, in mice. Respiratory gas analysis indicated that intragastric administration of AMG517 enhanced EM along with increasing locomotor activity in mice. Next, to clarify the possible involvement with afferent sensory nerves, including the vagus, we desensitized the capsaicin-sensitive sensory nerves of mice by systemic capsaicin treatment. In the desensitized mice, intragastric administration of AMG517 did not change EM and locomotor activity. Therefore, this study indicated that intragastric administration of AMG517 enhanced EM and increased locomotor activity via capsaicin-sensitive sensory nerves, including vagal afferents in mice. 相似文献
833.
Variation in the productivity of berberine between clonal cell lines derived from a culture strain of Thalictrum minus. var. hypoleucum was investigated during the period of successive transfer generations. There was a correlation between berberine productivity and growth in these clonal cultures. Although no significant difference was found in the secretory function as well as the qualitative pattern of alkaloids, there was wide variation in the yield of berberine among the clones. Some of the cell lines have shown a high stability throughout the successive subculturing, whereas the other lines tended to either decrease or increase the productivity continually before they have become more or less stable at low or high levels. After eight months of subculturing, one of the high-producing cell lines yielded 0.76 g of berberine per liter in 14 days of culture strain. In view of variations observed in both primary and secondary clones, the possible cause of the quantitative variation in berberine production in Thalictrum cultures is discussed.Abbreviations LS
Linsmaier and Skoog (1965)
- 2,4-D
2,4-dichlorophenoxyacetic acid
- BA
6-benzyladenine 相似文献
834.
The transduction of sodium salts occurs through a variety of mechanisms,
including sodium influx through amiloride-sensitive sodium channels,
anion-dependent sodium movement through intercellular junctions and
unidentified amiloride-insensitive mechanisms. Characterizations of sodium
transport in lingual epithelium mounted in Ussing chambers have focused
almost exclusively on epithelia containing only fungiform taste buds. In
the present study we have investigated sodium transport by measuring
NaCl-induced short-circuit current from lingual epithelia containing
fungiform, foliate, vallate and palatine taste buds in the hamster and the
rat. All areas show measurable sodium transport, yet significant
differences were noted between the epithelia from the rat and the hamster
and among the different epithelia within a single species in terms of
current density, transepithelial resistance and mucosal amiloride
sensitivity. In general, epithelia from the anterior tongue were of a lower
resistance and transported sodium more effectively than from the posterior
tongue. Moreover, fungiform- and vallate-containing epithelia in the rat
had a greater current density than did the corresponding tissues in the
hamster. Amiloride sensitivity also differed between the rat and the
hamster. In the hamster all gustatory areas showed some amiloride
sensitivity, while in the rat the vallate-containing epithelia were devoid
of amiloride- sensitive sodium transport. The results are consistent with
the interpretation that all chemosensitive areas may participate in the
detection of salts but the degree of salt transport and the mechanism of
transport is variable among different lingual epithelia and different
species.
相似文献
835.
Different strains of callus cultures of Lithospermum erythrorhizon showed wide variations in the production of shikonin derivatives. From these cultures, two high pigment-producing strains, whose content of shikonin derivatives are stable and similar to that of intact plant root, have been established by repeated selection. 相似文献
836.
837.
A novel chemotype (C type) having a lemon-like odor segregated out in the F2 progeny of a cross between PK and PL chemotypes ofPerilla frutescens. Chemical analysis of C-type plants revealed that geranial was the major component of essential oils in the leaves. Genetic analysis suggested that geranial is accumulated by individuals homozygous for two pairs of recessive, polymeric genes,fr
1 andfr
2, which are incapable of converting geranial into perillene. 相似文献
838.
839.
A total of 17 Pl and TAC clones each representing an assigned region of chromosome 5 were isolated from P1 and TAC genomic libraries of Arabidopsis thaliana Columbia, and their nucleotide sequences were determined. The length of the clones sequenced in this study summed up to 1,081,958 bp. As we have previously reported the sequence of 9,072,622 bp by analysis of 125 P1 and TAC clones, the total length of the sequences of chromosome 5 determined so far is now 10,154,580 bp. The sequences were subjected to similarity search against protein and EST databases and analysis with computer programs for gene modeling. As a consequence, a total of 253 potential protein-coding genes with known or predicted functions were identified. The positions of exons which do not show apparent similarity to known genes were also assigned using computer programs for exon prediction. The average density of the genes identified in this study was 1 gene per 4277 bp. Introns were observed in 74% of the potential protein genes, and the average number per gene and the average length of the introns were 4.3 and 168 bp, respectively. The sequence data and gene information are available on the World Wide Web database KAOS (Kazusa Arabidopsis data Opening Site) at http://www.kazusa.or.jp/arabi/. 相似文献
840.
The release of the benzylisoquinoline alkaloid berberine from cultured cells of Thalictrum minus into the medium proved to be temperature-dependent and was suppressed by such inhibitors of the plasma membrane-bound ATPase as vanadate and diethylstilbestrol. These results indicate that berberine is secreted through an energy-requiring process located in the plasma membrane of berberine-producing T. minus cells. This is the first finding that a secondary metabolite of plant cell culture is secreted by an active transport system.Abbreviations BAP
6-benzylaminopurine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- DES
diethylstilbestrol
- DMSO
dimethyl sulfoxide
- LS
Linsmaier and Skoog (1965)
- NAA
1-naphthaleneacetic acid 相似文献