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111.
112.
A petal‐specific InMYB1 promoter from Japanese morning glory: a useful tool for molecular breeding of floricultural crops 下载免费PDF全文
Mana Hirose Yasumasa Morita Atsushi Hoshino Shigeru Iida Yoshimi Oshima Nobutaka Mitsuda Masaru Ohme‐Takagi Katsuhiro Shiratake 《Plant biotechnology journal》2016,14(1):354-363
Production of novel transgenic floricultural crops with altered petal properties requires transgenes that confer a useful trait and petal‐specific promoters. Several promoters have been shown to control transgenes in petals. However, all suffer from inherent drawbacks such as low petal specificity and restricted activity during the flowering stage. In addition, the promoters were not examined for their ability to confer petal‐specific expression in a wide range of plant species. Here, we report the promoter of InMYB1 from Japanese morning glory as a novel petal‐specific promoter for molecular breeding of floricultural crops. First, we produced stable InMYB1_1kb::GUS transgenic Arabidopsis and Eustoma plants and characterized spatial and temporal expression patterns under the control of the InMYB1 promoter by histochemical β‐glucuronidase (GUS) staining. GUS staining patterns were observed only in petals. This result showed that the InMYB1 promoter functions as a petal‐specific promoter. Second, we transiently introduced the InMYB1_1 kb::GUS construct into Eustoma, chrysanthemum, carnation, Japanese gentian, stock, rose, dendrobium and lily petals by particle bombardment. GUS staining spots were observed in Eustoma, chrysanthemum, carnation, Japanese gentian and stock. These results showed that the InMYB1 promoter functions in most dicots. Third, to show the InMYB1 promoter utility in molecular breeding, a MIXTA‐like gene function was suppressed or enhanced under the control of InMYB1 promoter in Arabidopsis. The transgenic plant showed a conspicuous morphological change only in the form of wrinkled petals. Based on these results, the InMYB1 promoter can be used as a petal‐specific promoter in molecular breeding of floricultural crops. 相似文献
113.
Jitsuki?SawamuraEmail author Shigeru?Morishita Jun?Ishigooka 《Theoretical biology & medical modelling》2016,13(1):5
Background
Previously, we applied basic group theory and related concepts to scales of measurement of clinical disease states and clinical findings (including laboratory data). To gain a more concrete comprehension, we here apply the concept of matrix representation, which was not explicitly exploited in our previous work.Methods
Starting with a set of orthonormal vectors, called the basis, an operator Rj (an N-tuple patient disease state at the j-th session) was expressed as a set of stratified vectors representing plural operations on individual components, so as to satisfy the group matrix representation.Results
The stratified vectors containing individual unit operations were combined into one-dimensional square matrices [Rj]s. The [Rj]s meet the matrix representation of a group (ring) as a K-algebra. Using the same-sized matrix of stratified vectors, we can also express changes in the plural set of [Rj]s. The method is demonstrated on simple examples.Conclusions
Despite the incompleteness of our model, the group matrix representation of stratified vectors offers a formal mathematical approach to clinical medicine, aligning it with other branches of natural science.114.
Quantitative and antioxidative behavior of Trolox in rats’ blood and brain by HPLC‐UV and SMFIA‐CL methods 下载免费PDF全文
Mitsuhiro Wada Misato Wada Rie Ikeda Yuki Fuchigami Hironari Koyama Susumu Ohkawara Shigeru Kawakami Naotaka Kuroda Kenichiro Nakashima 《Luminescence》2016,31(2):414-418
Trolox, a water‐soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi‐microflow injection analysis, chemiluminescence detection and HPLC‐UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored. The antioxidative effects in blood (12.0 ± 2.1) and brain (8.4 ± 2.1, × 103 antioxidative effect % × min) also increased. Additionally, the areas under the curve (AUC)s0–360 (n = 3) for blood and brain calculated with quantitative data were 10.5 ± 1.2 and 9.7 ± 2.5 mg/mL × min, respectively. This result indicates that Trolox transferability through the blood–brain barrier is high. The increase in the antioxidative effects caused by Trolox in the blood and brain could be confirmed because good correlations between concentration and antioxidative effects (r ≥ 0.702) were obtained. The fact that Trolox can produce an antioxidative effect in rat brain was clarified. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
115.
Masatsugu Miyara Kanae Umeda Keishi Ishida Seigo Sanoh Shigeru Ohta 《Bioscience, biotechnology, and biochemistry》2016,80(6):1164-1167
Serum is an important component of cell culture media. The present study demonstrates contamination of intracellular protein extract by bovine serum albumin from the culture media and illustrates how this contamination can cause the misinterpretation of western blot results. Preliminary experiments can prevent the misinterpretation of some experimental results, and optimization of the washing process may enable specific protein detection. 相似文献
116.
Tsutomu Kataoka Manabu Fuchikami Shinji Nojima Nobuyuki Nagashima Motoaki Araki Jun Omura Tatsuhiro Miyagi Yasumasa Okamoto Shigeru Morinobu 《Genes, Brain & Behavior》2019,18(7)
Impaired fear memory extinction (Ext) is one of the hallmark symptoms of post‐traumatic stress disorder (PTSD). However, since the precise mechanism of impaired Ext remains unknown, effective interventions have not yet been established. Recently, hippocampal‐prefrontal brain‐derived neurotrophic factor (BDNF) activity was shown to be crucial for Ext in naïve rats. We therefore examined whether decreased hippocampal‐prefrontal BDNF activity is also involved in the Ext of rats subjected to a single prolonged stress (SPS) as a model of PTSD. BDNF levels were measured by enzyme‐linked immunosorbent assay (ELISA), and phosphorylation of TrkB was measured by immunohistochemistry in the hippocampus and medial prefrontal cortex (mPFC) of SPS rats. We also examined whether BDNF infusion into the ventral mPFC or hippocampus alleviated the impaired Ext of SPS rats in the contextual fear conditioning paradigm. SPS significantly decreased the levels of BDNF in both the hippocampus and mPFC and TrkB phosphorylation in the ventral mPFC. Infusion of BDNF 24 hours after conditioning in the infralimbic cortex (ILC), but not the prelimbic cortex (PLC) nor hippocampus, alleviated the impairment of Ext. Since amelioration of impaired Ext by BDNF infusion did not occur without extinction training, it seems the two interventions must occur consecutively to alleviate impaired Ext. Additionally, BDNF infusion markedly increased TrkB phosphorylation in the ILC of SPS rats. These findings suggest that decreased BDNF signal transduction might be involved in the impaired Ext of SPS rats, and that activation of the BDNF‐TrkB signal might be a novel therapeutic strategy for the impaired Ext by stress. 相似文献
117.
Kenta Watanabe Koji Seike Rumiko Kajihara Shigeru Montani Tomohiro Kuwae 《Global Change Biology》2019,25(3):1063-1077
Because coastal habitats store large amounts of organic carbon (Corg), the conservation and restoration of these habitats are considered to be important measures for mitigating global climate change. Although future sea‐level rise is predicted to change the characteristics of these habitats, its impact on their rate of Corg sequestration is highly uncertain. Here we used historical depositional records to show that relative sea‐level (RSL) changes regulated Corg accumulation rates in boreal contiguous seagrass–saltmarsh habitats. Age–depth modeling and geological and biogeochemical approaches indicated that Corg accumulation rates varied as a function of changes in depositional environments and habitat relocations. In particular, Corg accumulation rates were enhanced in subtidal seagrass meadows during times of RSL rise, which were caused by postseismic land subsidence and climate change. Our findings identify historical analogs for the future impact of RSL rise driven by global climate change on rates of Corg sequestration in coastal habitats. 相似文献
118.
119.
To find the cause of the skinning-induced fragility of frog skeletal muscle, the transverse relaxation process of 1H-NMR signals from skinned muscle was observed. A set of four characteristic exponentials well described the process. Aside from the extremely slow exponential component (time constant T2 > 0.4 s) representing surplus solution, the process was generally slower than that in living muscle. It had larger amplitudes of slow (T2 approximately 0.15 s) and intermediate (0.03 < T2 < 0.06 s) exponentials and had smaller amplitude and faster T2 in the rapid one (T2 < 0.03 s), suggesting that skinned muscle is more sol-like than intact myoplasm. To resolve their causes, we traced the exponentials following a stepwise treatment of living whole muscle to an isolated skinned fiber. Osmotic expansion of living muscle comparable to skinned muscle increased the intermediate exponential and decreased the rapid one without affecting T2. Subsequent chemical skinning markedly increased the slow exponential, decreased the rapid one, and slowed the intermediate one. The fiber isolation had no appreciable effect. Because l-carnosine at physiological concentration could not recover the skinning-induced difference, the difference would reflect the dilution and efflux of larger macromolecules, which stabilize myoplasm as a gel. 相似文献
120.
Epidermal hyperplasia and expansion of the interfollicular stem cell compartment in mutant mice with a C-terminal truncation of Patched1 总被引:1,自引:0,他引:1
Hedgehog (Hh) signaling is conserved from flies to humans and is indispensable in embryogenesis and adulthood. Patched (Ptc) encodes a receptor for Hh ligands and functions as a tumor suppressor. PTCH1 mutations in humans are found in basal cell carcinoma (BCC) and irradiated Ptc1(+/-) mice recapitulate this phenotype. However, due to embryonic lethality associated with the Ptc1 null mutation, its normal function in embryonic and adult skin remains unknown. Here we describe the epidermal phenotypes of a spontaneous and viable allele of Ptc1, Ptc1(mes), in which the C-terminal domain (CTD) is truncated. Ptc1(mes/mes) embryos display normal epidermal and hair follicle development. Postnatal Ptc1(mes/mes) skin displays severe basal cell layer hyperplasia and increased proliferation, while stratification of the suprabasal layers is mostly normal. Interestingly, truncation of the Ptc1 CTD did not result in skin tumors. However, long term labeling studies revealed a greater than three-fold increase in label-retaining cells in the interfollicular epidermis of Ptc1(mes/mes) adults, indicating possible expansion of the epidermal stem cell compartment. Increased expression of regulators of epidermal homeostasis, c-Myc and p63, was also observed in Ptc1(mes/mes) adult skin. These results suggest that the CTD of Ptc1 is involved in regulating epidermal homeostasis in mature skin. 相似文献