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991.
Glomerular endothelial cell injury plays an important role in the development and progression of diabetic nephropathy (DN). The expression and function of klotho in glomerular endothelial cells remain unclear. Thus, this study aimed to investigate the expression and the functional role of klotho in DN progression in mice and in high glucose (HG)-induced cell injury of human renal glomerular endothelial cells (HRGECs) and the underlying mechanism. In this study, HRGECs were cultured with media containing HG to induce endothelial cell injury and db/db mice were used as DN model mice. Klotho was overexpressed or knocked down in HRECs to evaluate its role in HG-induced HRGECs injury. klotho-overexpressing adenovirus (rAAV-klotho) was injected into db/db mice via the tail vein to further validate the protective effect of klotho in DN. Decreased klotho expression was observed in DN patients, DN mice, and HG-exposed HRGECs. Furthermore, klotho overexpression significantly abolished the HG-induced HRGECs injury and activation of Wnt/β-catenin pathway and RAAS. In contrast, klotho knockdown exerted the opposite effects. Moreover, klotho attenuated diabetic nephropathy in db/db mice, which was also associated with inhibition of the Wnt/β-catenin pathway and RAAS. In conclusion, klotho attenuates DN in db/db mice and ameliorates HG-induced injury of HRGECs. 相似文献
992.
Nitric oxide production, nitric oxide synthase (NOS) and mitochondrial nitrite-reducing activities in roots, leaves and stems
of different developmental stages were investigated, using potted 3-year-old apple (Malus domestica Borkh.) trees. The arginine-dependent NOS activity is sensitive to NOS inhibitor L-NAME and aminoguanidine (AG), with L-NAME
being more effective than AG. Endogenous NO production, NOS and mitochondrial nitrite-reducing activities are predominately
presented in young leaves and especially in young white roots and young stems. Root and stem mitochondria can reduce nitrite
to nitric oxide at the expense of NADH, however, this mitochondrial nitrite-reducing activity is absent in leaves. 相似文献
993.
994.
Pingyong Sun Wuhan Zhang Yihua Wang Qiang He Fu Shu Hai Liu Jie Wang Jianmin Wang Longping Yuan Huafeng Deng 《植物学报(英文版)》2016,58(10):836-847
Traits such as grain shape, panicle length and seed shattering, play important roles in grain yield and harvest. In this study, the cloning and functional analysis of PANICLE TRAITS 2 (PT2), a novel gene from the Indica rice Chuandali (CDL), is reported. PT2 is synonymous with Growth‐Regulating Factor 4 (OsGRF4), which encodes a growth‐regulating factor that positively regulates grain shape and panicle length and negatively regulates seed shattering. Higher expression of OsGRF4 is correlated with larger grain, longer panicle and lower seed shattering. A unique OsGRF4 mutation, which occurs at the OsmiRNA396 target site of OsGRF4, seems to be associated with high levels of OsGRF4 expression, and results in phenotypic difference. Further research showed that OsGRF4 regulated two cytokinin dehydrogenase precursor genes (CKX5 and CKX1) resulting in increased cytokinin levels, which might affect the panicle traits. High storage capacity and moderate seed shattering of OsGRF4 may be useful in high‐yield breeding and mechanized harvesting of rice. Our findings provide additional insight into the molecular basis of panicle growth. 相似文献
995.
Zhao Zhang Hiroshi Takeuchi Jing Gao DaGuang Wang Declan J. James Thomas F. J. Martin Masato Hirata 《The Journal of biological chemistry》2013,288(11):7769-7780
Membrane fusion for exocytosis is mediated by SNAREs, forming trans-ternary complexes to bridge vesicle and target membranes. There is an array of accessory proteins that directly interact with and regulate SNARE proteins. PRIP (phospholipase C-related but catalytically inactive protein) is likely one of these proteins; PRIP, consisting of multiple functional modules including pleckstrin homology and C2 domains, inhibited exocytosis, probably via the binding to membrane phosphoinositides through the pleckstrin homology domain. However, the roles of the C2 domain have not yet been investigated. In this study, we found that the C2 domain of PRIP directly interacts with syntaxin 1 and SNAP-25 but not with VAMP2. The C2 domain promoted PRIP to co-localize with syntaxin 1 and SNAP-25 in PC12 cells. The binding profile of the C2 domain to SNAP-25 was comparable with that of synaptotagmin I, and PRIP inhibited synaptotagmin I in binding to SNAP-25 and syntaxin 1. It was also shown that the C2 domain was required for PRIP to suppress SDS-resistant ternary SNARE complex formation and inhibit high K+-induced noradrenalin release from PC12 cells. These results suggest that PRIP inhibits regulated exocytosis through the interaction of its C2 domain with syntaxin 1 and SNAP-25, potentially competing with other SNARE-binding, C2 domain-containing accessory proteins such as synaptotagmin I and by directly inhibiting trans-SNARE complex formation. 相似文献
996.
Lei Wang Kunzheng Cai Yuting Chen Guoping Wang 《Biological trace element research》2013,152(2):275-283
Bacterial wilt caused by Ralstonia solanacearum is a serious soil-borne disease of Solanaceae crops. In this study, the soil microbial effects of silicon-induced tomato resistance against R. solanacearum were investigated through pot experiment. The results showed that exogenous 2.0 mM Si treatment reduced the disease index of bacterial wilt by 19.18 % to 52.7 % compared with non-Si-treated plants. The uptake of Si was significantly increased in the Si-treated tomato plants, where the Si content was higher in the roots than that in the shoots. R. solanacearum inoculation resulted in a significant increase of soil urease activity and reduction of soil sucrase activity, but had no effects on soil acid phosphatase activity. Si supply significantly increased soil urease and soil acid phosphatase activity under pathogen-inoculated conditions. Compared with the non-inoculated treatment, R. solanacearum infection significantly reduced the amount of soil bacteria and actinomycetes by 52.5 % and 16.5 %, respectively, but increased the ratio of soil fungi/soil bacteria by 93.6 %. After R. solanacearum inoculation, Si amendments significantly increased the amount of soil bacteria and actinomycetes and reduced soil fungi/soil bacteria ratio by 53.6 %. The results suggested that Si amendment is an effective approach to control R. solanacearum. Moreover, Si-mediated resistance in tomato against R. solanacearum is associated with the changes of soil microorganism amount and soil enzyme activity. 相似文献
997.
998.
Li Han Xuan Zhou Yiting Zhao Shusheng Zhu Lixia Wu Yunlu He Xiangrui Ping Xinqi Lu Wuying Huang Jie Qian Lina Zhang Xi Jiang Dan Zhu Chongyu Luo Saijie Li Qian Dong Qijing Fu Kaiyuan Deng Xin Wang Lei Wang Sheng Peng Jinsong Wu Weimin Li Jií Friml Youyong Zhu Xiahong He Yunlong Du 《植物学报(英文版)》2020,62(9):1433-1451
Endophytic fungi can be beneficial to plant growth. However, the molecular mechanisms underlying colonization of Acremonium spp. remain unclear.In this study, a novel endophytic Acremonium strain was isolated from the buds of Panax notoginseng and named Acremonium sp. D212. The Acremonium sp. D212 could colonize the roots of P. notoginseng,enhance the resistance of P. notoginseng to root rot disease, and promote root growth and saponin biosynthesis in P. notoginseng. Acremonium sp. D212 could secrete indole-3-acetic acid(IAA) and jasmonic acid(JA), and inoculation with the fungus increased the endogenous levels of IAA and JA in P. notoginseng. Colonization of the Acremonium sp. D212 in the roots of the rice line Nipponbare was dependent on the concentration of methyl jasmonate(Me JA)(2–15 μmol/L) and 1-naphthalenacetic acid(NAA)(10–20 μmol/L). Moreover, the roots of the JA signaling-defective coi1-18 mutant were colonized by Acremonium sp. D212 to a lesser degree than those of the wild-type Nipponbare and mi R393 boverexpressing lines, and the colonization was rescued by Me JA but not by NAA. It suggests that the cross-talk between JA signaling and the auxin biosynthetic pathway plays a crucial role in the colonization of Acremonium sp. D212 in host plants. 相似文献
999.
Yuhui Wen Yingcai Wang James D. Potter W. Glenn L. Kerrick 《Journal of molecular biology》2009,392(5):1158-103
The human cardiac troponin I (hcTnI) mutation R145W has been associated with restrictive cardiomyopathy. In this study, simultaneous measurements of ATPase activity and force in skinned papillary fibers from hcTnI R145W transgenic mice (Tg-R145W) were explored. Tg-R145W fibers showed an ∼ 13-16% increase in maximal Ca2+-activated force and ATPase activity compared to hcTnI wild-type transgenic mice. The force-generating cross-bridge turnover rate (g) and the energy cost (ATPase/force) were the same in all groups of fibers. Also, the Tg-R145W fibers showed a large increase in the Ca2+ sensitivity of both force development and ATPase. In intact fibers, the mutation caused prolonged force and intracellular [Ca2+] transients and increased time to peak force. Analysis of force and Ca2+ transients showed that there was a 40% increase in peak force in Tg-R145W muscles, which was likely due to the increased Ca2+ transient duration. The above cited results suggest that: (1) there would be an increase in resistance to ventricular filling during diastole resulting from the prolonged force and Ca2+ transients that would result in a decrease in ventricular filling (diastolic dysfunction); and (2) there would be a large (approximately 53%) increase in force during systole, which may help to partly compensate for diastolic dysfunction. These functional results help to explain the mechanisms by which these mutations give rise to a restrictive phenotype. 相似文献
1000.