R5002_12, a salt tolerant line of Phragmites communis Trin., which was obtained from ethyl methane sulfonate (EMS) treated callus selected under saline stress, was compared with its wild line in respect to their m...R5002_12, a salt tolerant line of Phragmites communis Trin., which was obtained from ethyl methane sulfonate (EMS) treated callus selected under saline stress, was compared with its wild line in respect to their molecular biological, physiological and biochemical characterizations. Five arbitrary primers were screened which showed differences in DNA amplified polymorphism between the variant and its wild line. Some new proteins appeared in the salt tolerant plant under salt stress. Electrophoresis of peroxidase and esterase also showed some differences in isozyme expression between them. The chlorophyll content of the variant was higher than that of the original variety, whether the plants were under salt stress or not.展开更多
AIM： To address the possibility that insulin-like growth factor （IGF）-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS： Huh-6 and HepG2, human hepato...AIM： To address the possibility that insulin-like growth factor （IGF）-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS： Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor （IGF-IR）. Inhibitors of IGF-IR （piclopodophyllin, PPP）, phosphatidyl-inositol （PI） 3-kinase （LY294002 and Wortmannin）, or mitogen-activated protein （MAP） kinase （PD98059） were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS： IGF-Ⅱ stimulated cells proliferated to 2.7 （269% ± 76%） （mean ± SD） （Huh-6） and 2.1 （211% ± 85%） times （HepG2）. IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% （Huh-6） and 39% ± 5% （HepG2）. LY294002 and Wortmannin suppressed the cell number to 30% ± 5% （Huh-6）, 44% ± 0.4% （HepG2）, 49% ± 1.0% （Huh-6） and 46% ± 1.1% （HepG2）, respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION： IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.展开更多
考察以0.55 g/100 mL L-精氨酸(精氨酸)/L-赖氨酸(赖氨酸)+1.5 g/100 mL NaCl溶液为提取剂提取的鸡胸肉蛋白的凝胶特性。差示扫描量热法和动态流变结果表明:与对照组相比,添加精氨酸/赖氨酸的提取剂所对应的蛋白提取物在加热过程中具有...考察以0.55 g/100 mL L-精氨酸(精氨酸)/L-赖氨酸(赖氨酸)+1.5 g/100 mL NaCl溶液为提取剂提取的鸡胸肉蛋白的凝胶特性。差示扫描量热法和动态流变结果表明:与对照组相比,添加精氨酸/赖氨酸的提取剂所对应的蛋白提取物在加热过程中具有3个明显的变性温度点和4个明显的温度区间,其在加热和冷却的过程中均具有更高的储能模量;添加精氨酸/赖氨酸的提取剂所对应的蛋白提取物形成的蛋白凝胶具有连续的三维网络结构、更高的保水性和凝胶强度以及更低的蒸煮损失。因此,提取剂中包含精氨酸/赖氨酸的蛋白提取物具有更好的凝胶特性,所形成的凝胶具有更好的保水和质构等特性。展开更多
14-3-3 proteins play an important role in the regulation of many cellular processes. The Arabidopsis vacuolar two-pore K＋ channel 1 （TPK1） interacts with the 14-3-3 protein GRF6 （GF14-λ）. Upon phosphorylation of...14-3-3 proteins play an important role in the regulation of many cellular processes. The Arabidopsis vacuolar two-pore K＋ channel 1 （TPK1） interacts with the 14-3-3 protein GRF6 （GF14-λ）. Upon phosphorylation of the putative binding motif in the N-terminus of TPK1, GRF6 binds to TPK1 and activates the potassium channel. In order to gain a deeper understanding of this 14-3-3-mediated signal transduction, we set out to identify the respective kinases, which regulate the phosphorylation status of the 14-3-3 binding motif in TPK1. Here, we report that the calcium-dependent protein kinases （CDPKs） can phosphorylate and thereby activate the 14-3-3 binding motif in TPK1. Focusing on the stress-activated kinase CPK3, we visualized direct and specific interaction of TPK1 with the kinase at the tonoplast in vivo. In line with its proposed role in K＋ homeostasis, TPK1 phosphorylation was found to be induced by salt stress in planta, and both cpk3 and tpkl mutants displayed salt-sensitive phenotypes. Molecular modeling of the TPK1-CPK3 interaction domain provided mechanistic insights into TPK1 stress-regulated phosphorylation responses and pinpointed two arginine residues in the N-terminal 14-3-3 binding motif in TPK1 critical for kinase interaction. Taken together, our studies provide evidence for an essential role of the vacuolar potassium channel TPK1 in salt-stress adaptation as a target of calcium-regulated stress signaling pathways involving Ca2＋, Ca2＋-dependent kinases, and 14-3-3 proteins.展开更多
文摘R5002_12, a salt tolerant line of Phragmites communis Trin., which was obtained from ethyl methane sulfonate (EMS) treated callus selected under saline stress, was compared with its wild line in respect to their molecular biological, physiological and biochemical characterizations. Five arbitrary primers were screened which showed differences in DNA amplified polymorphism between the variant and its wild line. Some new proteins appeared in the salt tolerant plant under salt stress. Electrophoresis of peroxidase and esterase also showed some differences in isozyme expression between them. The chlorophyll content of the variant was higher than that of the original variety, whether the plants were under salt stress or not.
基金Supported by the Japan Society for the Promotion of Science (JSPS) (16590577) and the Kawano Masanori Memorial Foundation for Promotion of Pediatrics (15-6)
文摘AIM： To address the possibility that insulin-like growth factor （IGF）-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS： Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor （IGF-IR）. Inhibitors of IGF-IR （piclopodophyllin, PPP）, phosphatidyl-inositol （PI） 3-kinase （LY294002 and Wortmannin）, or mitogen-activated protein （MAP） kinase （PD98059） were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS： IGF-Ⅱ stimulated cells proliferated to 2.7 （269% ± 76%） （mean ± SD） （Huh-6） and 2.1 （211% ± 85%） times （HepG2）. IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% （Huh-6） and 39% ± 5% （HepG2）. LY294002 and Wortmannin suppressed the cell number to 30% ± 5% （Huh-6）, 44% ± 0.4% （HepG2）, 49% ± 1.0% （Huh-6） and 46% ± 1.1% （HepG2）, respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION： IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.
文摘考察以0.55 g/100 mL L-精氨酸(精氨酸)/L-赖氨酸(赖氨酸)+1.5 g/100 mL NaCl溶液为提取剂提取的鸡胸肉蛋白的凝胶特性。差示扫描量热法和动态流变结果表明:与对照组相比,添加精氨酸/赖氨酸的提取剂所对应的蛋白提取物在加热过程中具有3个明显的变性温度点和4个明显的温度区间,其在加热和冷却的过程中均具有更高的储能模量;添加精氨酸/赖氨酸的提取剂所对应的蛋白提取物形成的蛋白凝胶具有连续的三维网络结构、更高的保水性和凝胶强度以及更低的蒸煮损失。因此,提取剂中包含精氨酸/赖氨酸的蛋白提取物具有更好的凝胶特性,所形成的凝胶具有更好的保水和质构等特性。
文摘为改善低盐(1g/100mLNaCl)环境中肌原纤维蛋白的功能特性,研究不同添加量的焦磷酸钠(tetrasodium pyrophosphate,TSPP)、三聚磷酸钠(sodium tripolyphosphate,STPP)、六偏磷酸钠(sodium hexametaphosphate,SHMP)对白鲢鱼肌原纤维蛋白结构和功能特性的影响。结果表明:低盐条件下,随着磷酸盐添加量的增加,肌原纤维蛋白的溶解度、表面疏水性、乳化性均呈上升趋势;3种磷酸盐均使肌原纤维蛋白引入磷酸基团;添加0.2~0.5 g/100 mL STPP能够降低肌原纤维蛋白热解速率,提升蛋白质热稳定性,其中0.4 g/100 mL STPP修饰的蛋白质磷酸化程度最大,此时大量的磷酸根基团与肌原纤维蛋白结合;TSPP和STPP更有利于蛋白质的聚集,而SHMP磷酸化的蛋白质更稳定。综上,0.4 g/100 mL STPP对低盐条件下肌原纤维蛋白功能特性具有更好的改善作用。
基金the Austrian Science Foundation (FWF) to M.T.，grants of the DFG to R.H.，T.D.M.，D.B.
文摘14-3-3 proteins play an important role in the regulation of many cellular processes. The Arabidopsis vacuolar two-pore K＋ channel 1 （TPK1） interacts with the 14-3-3 protein GRF6 （GF14-λ）. Upon phosphorylation of the putative binding motif in the N-terminus of TPK1, GRF6 binds to TPK1 and activates the potassium channel. In order to gain a deeper understanding of this 14-3-3-mediated signal transduction, we set out to identify the respective kinases, which regulate the phosphorylation status of the 14-3-3 binding motif in TPK1. Here, we report that the calcium-dependent protein kinases （CDPKs） can phosphorylate and thereby activate the 14-3-3 binding motif in TPK1. Focusing on the stress-activated kinase CPK3, we visualized direct and specific interaction of TPK1 with the kinase at the tonoplast in vivo. In line with its proposed role in K＋ homeostasis, TPK1 phosphorylation was found to be induced by salt stress in planta, and both cpk3 and tpkl mutants displayed salt-sensitive phenotypes. Molecular modeling of the TPK1-CPK3 interaction domain provided mechanistic insights into TPK1 stress-regulated phosphorylation responses and pinpointed two arginine residues in the N-terminal 14-3-3 binding motif in TPK1 critical for kinase interaction. Taken together, our studies provide evidence for an essential role of the vacuolar potassium channel TPK1 in salt-stress adaptation as a target of calcium-regulated stress signaling pathways involving Ca2＋, Ca2＋-dependent kinases, and 14-3-3 proteins.
