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51.
Loutfy N El-Tayeb MA Hassanen AM Moustafa MF Sakuma Y Inouhe M 《Journal of plant research》2012,125(1):173-184
Salicylic acid (SA) controls growth and stress responses in plants. It also induces drought tolerance in plants. In this paper,
four wheat (Triticum aestivum L.) cultivars with different drought responses were treated with SA in three levels of drain (90, 60, 30% of maximum field
capacity) to examine its interactive effects on drought responses and contents of osmotic solutes that may be involved in
growth and osmotic adjustment. Under drought condition, the cultivars Geza 164 and Sakha 69 had the plant biomass and leaf
relative water content (LRWC) greater than the cultivars Gemaza 1 and Gemaza 3. In all cultivars, drought stress decreased
the biomass, LRWC, and the contents of inorganic solutes (Ca, K, Mg) and largely increased the contents of organic solutes
(soluble sugars and proline). By contrast, SA increased the biomass, LRWC and the inorganic and organic solute contents, except
proline. Correlation analysis revealed that the LRWC correlated positively with the inorganic solute contents but negatively
with proline in all cultivars. SA caused maximum accumulations of soluble sugars in roots under drought. These results indicated
that SA-enhanced tolerance might involve solute accumulations but independently of proline biosynthesis. Drought-sensitive
cultivars had a trait lowering Ca and K levels especially in shoots. Possible functions of the ions and different traits of
cultivars were discussed. 相似文献
52.
Sayaka Sukegawa Ryuta Sakuma Seiga Ohmine Hiroaki Takeuchi Yasuhiro Ikeda Shoji Yamaoka 《PloS one》2014,9(10)
Old world monkey TRIM5α is a host factor that restricts human immunodeficiency virus type-1 (HIV-1) infection. Previously, we reported that rhesus macaque TRIM5α (RhTRIM5α) restricts HIV-1 production by inducing degradation of precursor Gag. Since suppressor of cytokine signaling 1 (SOCS1) is known to enhance HIV-1 production by rescuing Gag from lysosomal degradation, we examined if SOCS1 is involved in RhTRIM5α-mediated late restriction. Over-expression of SOCS1 restored HIV-1 production in the presence of RhTRIM5α to a level comparable to that in the absence of RhTRIM5α in terms of titer and viral protein expression. Co-immunoprecipitation studies revealed that SOCS1 physically interacted with RhTRIM5α. Over-expression of SOCS1 affected RhTRIM5α expression in a dose-dependent manner, which was not reversed by proteasome inhibitors. In addition, SOCS1 and RhTRIM5α were detected in virus-like particles. These results suggest that SOCS1 alleviates RhTRIM5α-mediated regulation in the late phase of HIV-1 life cycle probably due to the destabilization of RhTRIM5α. 相似文献
53.
The effects of 13-hydroperoxyoctadecadienoic acid (13-HPODE) on the cytosolic or microsomal acyl-CoA hydrolase (ACH) activity in rabbit kidney medulla and on the ACH-mediated prostaglandin (PG) formation from arachidonoyl-CoA (AA-CoA) were examined. 13-HPODE (10, 20, and 50 microM) had no effect on the cytosolic ACH activity but significantly inhibited the activity of the microsomal enzyme (43-57% inhibition). PG formation was measured as follows: AA-CoA (20 nmol) was preincubated with the cytosolic or microsomal fraction (as the source of ACH) in the presence or absence of 13-HPODE for 5 min at 37 degrees C, followed by incubation with the microsomal fraction (as the source of PG-synthesizing enzymes), hydroquinone and reduced glutathione for 5 min at 37 degrees C, and the PGs formed were measured by HPLC, with use of 9-anthryldiazomethane for derivatization. 13-HPODE reduced the PG formation when the microsomal fraction, but not the cytosolic fraction, was used as the source of ACH (10, 20, and 50 microM; 28-55% inhibition). These results suggest that 13-HPODE may modulate PG levels in rabbit kidney medulla by inhibiting the microsomal ACH activity. 相似文献
54.
Receptor-type protein tyrosine phosphatases (RPTPs) are considered to transduce extracellular signals across the membrane through changes in their PTP activity, however, our understanding of the regulatory mechanism is still limited. Here, we show that pleiotrophin (PTN), a natural ligand for protein tyrosine phosphatase receptor type Z (Ptprz) (also called PTPzeta/RPTPbeta), inactivates Ptprz through oligomerization and increases the tyrosine phosphorylation of substrates for Ptprz, G protein-coupled receptor kinase-interactor 1 (Git1) and membrane associated guanylate kinase, WW and PDZ domain containing 1 (Magi1). Oligomerization of Ptprz by an artificial dimerizer or polyclonal antibodies against its extracellular region also leads to inactivation, indicating that Ptprz is active in the monomeric form and inactivated by ligand-induced oligomerization. 相似文献
55.
Formation of trichothecenes by Fusarium solani var. coeruleum and Fusarium sambucinum in potatoes. 下载免费PDF全文
A A el-Banna P M Scott P Y Lau T Sakuma H W Platt V Campbell 《Applied microbiology》1984,47(5):1169-1171
Fusarium solani var. coeruleum can form deoxynivalenol in potato tubers and in liquid medium, although concentrations observed in the rot were highly variable; acetyldeoxynivalenol and HT-2 toxin were detected in 1 to 3 tubers only (of 57). Trichothecenes were also detected in a very few (3 of 20) cultures of Fusarium sambucinum in potato tubers. 相似文献
56.
57.
Background
High expectations regarding therapy are reported to have positive effects on future therapeutic course and related behavior. Some individuals are aware of feelings of comfort immediately after a relaxation therapy session.Methods
Heart rate variability biofeedback (HRV-BF) therapy using a relaxation technique called resonant breathing was administered to 44 family caregivers who felt burdened by their work caring for family members with cancer. We prospectively evaluated how the level of comfort participants were aware of immediately after an initial therapy session affected their expectations regarding the therapy, as well as future quality of life (QOL) and autonomic function. This study was a secondary analysis of a randomized, open-label study titled “Self-care system for family caregivers of cancer patients using resonant breathing with a portable home device”.Results
Among the participants, 56.8% were aware of a feeling of comfort immediately after an initial therapy session. Participants were then divided into two groups according to the presence or absence of their awareness of comfort. Expectation levels regarding the therapy were significantly increased in the awareness group after the therapy session (P?=?0.003). No main effect between groups was observed for heart rate variability (HRV) during therapy (P?=?0.949). Four weeks after the initial therapy session, QOL improved and HRV increased in the awareness group (P?<?0.001).Conclusions
Better outcomes in the awareness group were not associated with HRV during therapy. A feeling of comfort immediately after a therapy session may have positive effects on future QOL and autonomic function by raising participants’ expectations of the therapy.Trial registration
UMIN000021639. Registered 27 March 201658.
Hideki Shinno Chiseko Noda Keiji Tanaka Akira Ichihara 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,633(3)
L-Lysine-2-oxoglutarate reductase (EC 1.5.1.8, NADP+) in the liver of adult rats increased 4–5-times when the animals were treated with alloxan. In diabetic rats injection of insulin or adrenalectomy prevented the increase in enzyme activity. The activity of the similar enzyme in kidney was not changed by these treatments. The enzyme activity in primary cultured adult rat hepatocytes was also induced by addition of dexamethasone and glucagon together, and glucagon could be replaced by dibutyryl cyclic AMP. Insulin inhibited the induction. The hormonal induction was also inhibited by actinomycin D and by cycloheximide. During development of rats, fetal liver showed very low activity, but the activity appeared on day 1 after birth and then increased rapidly, reaching the adult level by day 5. The activity of the kidney enzyme increased more slowly and reached the adult level 1 month after birth. Intra-uterine injection of glucagon caused precocious induction of the liver enzyme in fetuses. These results indicate that the activity of L-lysine-2-oxoglutarate reductase in the adult liver and in part in neonatal liver also, is controlled by both glucagon and glucocorticoid. 相似文献
59.
Junichi Matsubara Masaya Ono Kazufumi Honda Ayako Negishi Hideki Ueno Takuji Okusaka Junji Furuse Koh Furuta Emiko Sugiyama Yoshiro Saito Nahoko Kaniwa Junichi Sawada Ayako Shoji Tomohiro Sakuma Tsutomu Chiba Nagahiro Saijo Setsuo Hirohashi Tesshi Yamada 《Molecular & cellular proteomics : MCP》2010,9(4):695-704
60.
The Extracellular A-loop of Dual Oxidases Affects the Specificity of Reactive Oxygen Species Release
Takehiko Ueyama Megumi Sakuma Yuzuru Ninoyu Takeshi Hamada Corinne Dupuy Miklós Geiszt Thomas L. Leto Naoaki Saito 《The Journal of biological chemistry》2015,290(10):6495-6506
NADPH oxidase (Nox) family proteins produce superoxide (O2⨪) directly by transferring an electron to molecular oxygen. Dual oxidases (Duoxes) also produce an O2⨪ intermediate, although the final species secreted by mature Duoxes is H2O2, suggesting that intramolecular O2⨪ dismutation or other mechanisms contribute to H2O2 release. We explored the structural determinants affecting reactive oxygen species formation by Duox enzymes. Duox2 showed O2⨪ leakage when mismatched with Duox activator 1 (DuoxA1). Duox2 released O2⨪ even in correctly matched combinations, including Duox2 + DuoxA2 and Duox2 + N-terminally tagged DuoxA2 regardless of the type or number of tags. Conversely, Duox1 did not release O2⨪ in any combination. Chimeric Duox2 possessing the A-loop of Duox1 showed no O2⨪ leakage; chimeric Duox1 possessing the A-loop of Duox2 released O2⨪. Moreover, Duox2 proteins possessing the A-loops of Nox1 or Nox5 co-expressed with DuoxA2 showed enhanced O2⨪ release, and Duox1 proteins possessing the A-loops of Nox1 or Nox5 co-expressed with DuoxA1 acquired O2⨪ leakage. Although we identified Duox1 A-loop residues (His1071, His1072, and Gly1074) important for reducing O2⨪ release, mutations of these residues to those of Duox2 failed to convert Duox1 to an O2⨪-releasing enzyme. Using immunoprecipitation and endoglycosidase H sensitivity assays, we found that the A-loop of Duoxes binds to DuoxA N termini, creating more stable, mature Duox-DuoxA complexes. In conclusion, the A-loops of both Duoxes support H2O2 production through interaction with corresponding activators, but complex formation between the Duox1 A-loop and DuoxA1 results in tighter control of H2O2 release by the enzyme complex. 相似文献