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591.
The taxon currently known asSargassum sagamianum is shown to include forms that are distinguishable from each other at specific level.S. sagamianum Yendo (sensu stricto) has a conical holdfast, branched upright stem, main branches triquetrous with sharp edges, leaves with sparsely serrate margins, and triquetrous female receptacles which mature in autumn.S. yamadae Yoshida et T. Konno spec. nov. has a creeping stem adhering to the substratum by attaching discs forming later a solid discoid holdfast, and simple spatulate receptacles which mature in spring to early summer.S. okamurae Yoshida et T. Konno spec. nov. is characterized by a creeping stem adhering by small attaching discs, its flat branches, linear lanceolate leaves with entire margins, and forked receptacles which mature in late autumn.S. yezoense (Yamada) Yoshida et T. Konno stat. nov. is considered as a distinct species with its creeping stem with a few attaching discs, its leaves not retroflexed, by its main branch having rounded edges, and simple spatulate receptacles maturing in summer. 相似文献
592.
Marilyn M. Belarmino Toshinori Abe Takeo Sasahara 《Plant Cell, Tissue and Organ Culture》1996,46(3):195-202
Experiments were conducted to asymmetrically fuse protoplasts from sweet potato (Ipomoea batatas L. Lam.) and its wild relativesI. trifida Don. andI. lacunosa L. Protoplasts of sweet potato were treated with iodoacetamide, whereas those ofI. trifida Don. andI. lacunosa L. were irradiated with X-rays. The asymmetric protoplast fusion was carried out by the electrofusion method and by polyethylene glycol treatment. Electrically-fused protoplasts initiated cell division, and then formed calli earlier than the polyethylene glycol-fused protoplasts. Plant regeneration occurred only in electrofused calli, suggesting that polyethylene glycol had some toxic effect on plant regeneration ability. Analysis of peroxidase isozymes confirmed the interspecific hybrid characteristics of both the fusion-derived calli and regenerated plants. 相似文献
593.
594.
Whole-genome characterization of lung adenocarcinomas lacking alterations in the RTK/RAS/RAF pathway
Jian Carrot-Zhang Xiaotong Yao Siddhartha Devarakonda Aditya Deshpande Jeffrey S. Damrauer Tiago Chedraoui Silva Christopher K. Wong Hyo Young Choi Ina Felau A. Gordon Robertson Mauro A.A. Castro Lisui Bao Esther Rheinbay Eric Minwei Liu Tuan Trieu David Haan Christina Yau Toshinori Hinoue Marcin Imielinski 《Cell reports》2021,34(5):108707
595.
Masamoto Kazumori; Kinoshita Toshinori; Shimazaki Ken-ichiro 《Plant & cell physiology》1993,34(6):935-938
Photosynthetic pigments of Vicia guard cell protoplasts (GCPs)from abaxial epidermis were analyzed by reverse-phase HPLC.Violaxanthin decreased and zeaxanthin increased in GCPs afterlight illumination. The epoxidation state of GCPs decreasedfrom 0.82 (dark) to 0.37 (light), suggesting operation of thexanthophyll cycle in GCPs of Vicia faba. (Received March 15, 1993; Accepted May 10, 1993) 相似文献
596.
The effect of gossypol on energy metabolism of round spermatids of rats was examined. When spermatids were treated with various concentrations of gossypol for 30 min at 32 degrees C, a biphasic response (stimulation at low concentrations and inhibition at high concentrations) was seen in pyruvate and CO2 production from lactate. At the early period of incubation, gossypol at even high concentrations stimulated CO2 production to an extent similar to that stimulated by 2,4-dinitrophenol (DNP). At longer periods of incubation, however, the rates of CO2 production from lactate dropped to those seen in the rotenone-treated cells. The rates of oxygen consumption were not increased further by DNP when cells were pretreated with gossypol. The adenosine triphosphate (ATP) content in spermatids was reduced markedly, although lactate oxidation to CO2 and mitochondrial respiration were stimulated by gossypol. These results suggest that gossypol probably exerts its effect on spermatids by uncoupling respiratory chain and oxidative phosphorylation. 相似文献
597.
Shimazaki Ken-ichiro; Omasa Kenji; Kinoshita Toshinori; Nishimura Mitsuo 《Plant & cell physiology》1993,34(8):1321-1327
Blue light-dependent proton extrusion in guard cell protoplastsfrom Vicia faba and light-dependent stomatal opening in theepidermis of Commelina benghalensis are inhibited by the calmodulin(CaM) antagonist, N-(6-aminohexyl)-5-chloro-l-naphthalenesulfononamide(W-7) and the myosin light chain kinase (MLCK) inhibitor, 1-(5-iodonaphthalene-1-sulfonyl)-lH-hexahydro-1,4-diazepine (ML-7) [Shimazaki, K., Kinoshita, T.and Nishimura, M. (1992) Plant Physiol. 99: 1416]. We now suggestthat the inhibition occurs in the blue light signaling pathwaywithout affecting the proton pump. Addition of fusicoccin (FC),an activator of H+-ATPase, to the protoplasts and the epidermiswhose blue light-dependent proton extrusion and light-dependentstomatal opening had been inhibited by W-7 and ML-7, inducedboth proton extrusion and stomatal opening, respectively. Bluelight-dependent proton extrusion was inhibited by K-252a, awide-range inhibitor of protein kinases, and KT5926, a selectiveinhibitor of MLCK. FC induced proton extrusion in the presenceof K-252a and KT5926. In contrast, phenylmercuric acetate (PMA),carbonyl cyanide-m-chlorophenylhydrazone (CCCP) and N, N'-dicyclohexylcarbodiimide(DCCD) inhibited both the proton extrusion and stomatal opening,but FC did not induce the responses. These results suggest thatW-7, ML-7, K-252a and KT5926 inhibit the signal transductionprocess by which the perception of blue light is transducedinto activation of the proton pump in guard cells, and thatMLCK or MLCK-like protein is involved in the blue light responseof stomata. The possibility that calcium-dependent, calmodulinindependent protein kinase [Harper, J.F. et al. (1991) Science252: 951] functions rather than MLCK in the blue light responseof stomata should be noted, however. (Received July 23, 1993; Accepted September 30, 1993) 相似文献
598.
Ovarian cells of pregnant rats were cultured with synthetic progestins (R5020, R2323), dexamethasone and RU486. Progesterone and 20 alpha-hydroxy-pregn-4-en-3-one (20 alpha-dihydroprogesterone) in the medium were measured by specific radioimmunoassay. Both R5020 and R2323 increased concentrations of these intrinsic progestins. RU486 decreased concentrations of progesterone, however, the addition of R5020 or R2323 counteracted this action. Immature hypophysectomized rats treated with pregnant mare serum gonadotropin (PMS) and human chorionic gonadotropin (hCG) were administered with RU486; the serum levels of progesterone and 20 alpha-dihydroprogesterone tended to decrease. R5020 and R2323 inhibited the effect of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), whereas RU486 did not. Inhibition of the cholesterol side chain cleavage enzyme (CSCC) by RU486 was more marked than that by R5020 or R2323. These results show that RU486 decreases progesterone synthesis in cultured ovarian cells. A part of the mechanism may involve an inhibition of CSCC. 相似文献