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101.
102.
荷叶铁线蕨自然居群的遗传多样性研究 总被引:6,自引:0,他引:6
荷叶铁线蕨(Adiantumreniformevar. sinense)为我国特有植物,具有重要的经济价值,目前仅分布于重庆的少数地区。近几十年来,由于过度开发,该种的分布范围日益缩小,已处于灭绝的边缘。本研究利用等位酶标记检测了荷叶铁线蕨 6个自然居群共 136个个体的遗传多样性,共检测到了 5个酶系统的 14个位点,获得了 7个多态位点。结果表明:与其他蕨类植物相比,荷叶铁线蕨居群内的遗传多样性水平比较低。平均每位点的有效等位基因数(Ae)为 1. 778,多态位点百分率(P)为 0. 441,期望杂合度(He)为 0. 199,观察杂合度 (Ho)为 0. 235。其居群间的遗传分化也很低,居群间的遗传变异仅占总变异的 1. 49%,而 98. 51%的变异存在于居群内部。采用Hardy Wein berg平衡和固定指数F对荷叶铁线蕨的居群遗传结构进行了分析,结果表明其种群可能是以配子体间异交为主的混合交配体系。导致荷叶铁线蕨濒危的主要原因是生境的破坏以及过度开采所导致的生境片断化使其居群变小、近交率加大、遗传变异趋低,降低了其生存以及进化的潜力。 相似文献
103.
在对产琥珀酸放线杆菌代谢分析的基础上选育出高产突变株对琥珀酸的工业生物转化有重要意义.在矩阵分析代谢通量基础上,围绕柔性节点下的副产物乙酸及乙醇的降低分别实施软X诱变及定点突变选育,并对比分析了突变株与出发株相关酶活及基因序列变化.针对出发株的流量分析显示产物琥珀酸的代谢通量为1.78(mmol/g/h),主要副产物乙酸与乙醇的代谢通量分别为(0.60mmol/g/h)和(1.04 mmol/g/h),并发现乙醇代谢加剧了琥珀酸合成中的H电子供体的不足;筛选出的氟乙酸抗性突变株S.JST1的乙酸代谢通量降低了96%,为0.024(mmol/g/h),酶活检测表明磷酸乙酰转移酶(Pta)的酶比活力从602降低到74,进一步的序列对比分析发现pta突变基因中产生了一个突变位点:adh定点复合突变株S.JST2的乙醇代谢通量降低了98%,为0.020(mmol/g/h),酶活检测表明Adh的酶比活力从585降低到62.最终突变株S.JST2琥珀酸累积产量达65.7 g/L.围绕产琥珀酸放线杆菌Pta及Adh酶活的降低实施定向选育,在降低副产物流量的同时,有助于改善细胞H供体代谢平衡进而提高琥珀酸的流量.所获突变株具有工业应用潜力. 相似文献
104.
Yaoyao Hou Yingjun Fan Xian Xia Jicheng Pan Jianjun Hou Xixia Liu Xinpeng Chen 《Acta biochimica et biophysica Sinica》2021,(8):1037-1043
Ubiquitin-specific protease 31 (USP31) is a member of deubiquitinase family that is involved in nuclear factor-κB activation and sarcomagenesis.However,little i... 相似文献
105.
Shishuai Meng Kai Kang Dongsheng Fei Songlin Yang Shangha Pan Kaijiang Yu Mingyan Zhao 《Experimental Animals》2022,71(3):305
Infection-associated inflammation and coagulation are critical pathologies in sepsis-induced acute lung injury (ALI). This study aimed to investigate the effects of microRNA-363-3p (miR-363-3p) on sepsis-induced ALI and explore the underlying mechanisms. A cecal ligation and puncture-induced septic mouse model was established. The results of this study suggested that miR-363-3p was highly expressed in lung tissues of septic mice. Knockdown of miR-363-3p attenuated sepsis-induced histopathological damage, the inflammation response and oxidative stress in lung tissues. Furthermore, knockdown of miR-363-3p reduced the formation of platelet-derived microparticles and thrombin generation in blood samples of septic mice. Downregulation of miR-363-3p suppressed sphingosine-1-phosphate receptor 1 (S1PR1) expression in lung tissues and subsequently inactivated the nuclear factor kappa-B ligand (NF-κB) signaling. A luciferase reporter assay confirmed that miR-363-3p directly targeted the 3’-untranslated region of the mouse S1pr1 mRNA. Collectively, our study suggests that inactivation of NF-κB signaling is involved in the miR-363-3p/S1PR1 axis-mediated protective effect on septic ALI. 相似文献
106.
Jinfa Ye Yiming Wu Jintao Pan Shundong Cai Yuhang Cheng Chengchao Chu Min Su 《Luminescence》2024,39(2):e4658
The eye is a very important organ, and keratitis, corneal neovascularization, floaters, age-related macular degeneration, and other vision problems have seriously affected people's quality of life. Among the ophthalmic treatments, laser photocoagulations have been proposed and have shown therapeutic effects in clinical settings. However, corneal thinning and bleeding lesions induced by laser damage have led to limit its applications. To treat the issues of traditional hyperthermia treatments, photosensitizers [e.g., indocyanine green (ICG)] have been investigated to increase the therapeutic effects of corneal neovascularization and choroidal neovascularization. In the recent study, with the help of ICG, laser-induced nanobubble was proposed to treat vitreous opacities. The developed strategies could enlarge the effect of laser irradiation and reduce the side effects, so as to expand the scope of laser treatments in clinical ophthalmic diseases. 相似文献
107.
Andi Zhang Yi Pan Hao Wang Rui Ding Tianyuan Zou Dongye Guo Yilin Shen Peilin Ji Weiyi Huang Qing Wen Quan Wang Haixia Hu Jichang Wu Mingliang Xiang Bin Ye 《Aging cell》2024,23(4):e14091
The pathogenesis of age-related hearing loss (ARHL) remains unclear. OPA1 is the sole fusion protein currently known to be situated in the inner mitochondrial membrane, which is pivotal for maintaining normal mitochondrial function. While it has already been demonstrated that mutations in OPA1 may lead to hereditary deafness, its involvement in the occurrence and development of ARHL has not been previously explored. In our study, we constructed D-gal-induced senescent HEI-OC1 cells and the cochlea of C57BL/6J mice with a mutated SUMOylation site of SIRT3 using CRISPR/Cas9 technology. We found enhanced L-OPA1 processing mediated by activated OMA1, and increased OPA1 acetylation resulting from reductions in SIRT3 levels in senescent HEI-OC1 cells. Consequently, the fusion function of OPA1 was inhibited, leading to mitochondrial fission and pyroptosis in hair cells, ultimately exacerbating the aging process of hair cells. Our results suggest that the dysregulation of mitochondrial dynamics in cochlear hair cells in aged mice can be ameliorated by activating the SIRT3/OPA1 signaling. This has the potential to alleviate the senescence of cochlear hair cells and reduce hearing loss in mice. Our study highlights the significant roles played by the quantities of long and short chains and the acetylation activity of OPA1 in the occurrence and development of ARHL. This finding offers new perspectives and potential targets for the prevention and treatment of ARHL. 相似文献
108.
The electrocatalytic preparation of hydrogen at different pH values not only achieves excellent device performance but also promotes the application of reactive oxygen species (ROS) clearance and hydrogen anti-inflammation. However, it is difficult to develop materials that simultaneously achieve these excellent properties. Herein, the preparation of beaded necklace-like Co9Se8 microspheres using a general and facile synthetic strategy is reported. The Co9Se8-modified electrode has three applications: efficient water splitting for enhanced performance, ROS scavenging, and hydrogen anti-inflammatory activity. Experiments, high-angle-annular-dark-field scanning transmission electron microscopy, and density functional theory calculations indicate that the reconstructed Co(OH)2 plays a vital role in the oxygen evolution reaction and that the transition from *O to *OOH is the actual rate-determining step. The Co9Se8 material, with its unique beaded necklace-like structure, exhibits exceptional hydrogen production capabilities in phosphate buffer solution (pH 7.4). In particular, hydrogen produce under neutral conditions can effectively reduce ROS levels and significantly inhibit inflammation-related pathological processes, playing a unique antioxidant and anti-inflammatory role at the cellular level. The obtained results indicate that the as-synthesized Co9Se8 is more suitable for water splitting, ROS scavenging, and hydrogen anti-inflammatory applications, outperforming other transition metal electrodes and rendering practical industrial and clinical applications. 相似文献
109.
Yuhan Lin Penglin Xia Fangyu Cao Cheng Zhang Yajie Yang Haitao Jiang Haishan Lin Hu Liu Ruling Liu Xiaodong Liu Jianming Cai 《Journal of cellular and molecular medicine》2023,27(2):246
Radiation‐induced intestinal injury (RIII) is a common complication after radiation therapy in patients with pelvic, abdominal, or retroperitoneal tumours. Recently, in the model of DSS (Dextran Sulfate Sodium Salt) ‐induced intestinal inflammatory injury, it has been found in the study that transgenic mice expressing hVDR in IEC (Intestinal Epithelial Cell) manifest highly anti‐injury properties in colitis, suggesting that activated VDR in the epithelial cells of intestine may inhibit colitis by protecting the mucosal epithelial barrier. In this study, we investigated the effect of the expression and regulation of VDR on the protection of RIII, and the radiosensitivity in vitro experiments, and explored the initial mechanism of VDR in regulating radiosensitivity of IEC. As a result, we found that the expression of VDR in intestinal tissues and cells in mice can be induced by ionizing radiation. VDR agonists are able to prolong the average survival time of mice after radiation and reduce the radiation‐induced intestinal injury. For lack of vitamin D, the radiosensitivity of intestinal epithelial cells in mice increased, which can be reduced by VDR activation. Ensuing VDR activation, the radiation‐induced intestinal stem cells damage is decreased, and the regeneration and differentiation of intestinal stem cells is promoted as well. Finally, on the basis of sequencing analysis, we validated and found that VDR may target the HIF/PDK1 pathway to mitigate RIII. We concluded that agonism or upregulation of VDR expression attenuates radiation‐induced intestinal damage in mice and promotes the repair of epithelial damage in intestinal stem cells. 相似文献
110.
Rhizobial migration toward roots mediated by FadL-ExoFQP modulation of extracellular long-chain AHLs
Yuan-Yuan Ji Biliang Zhang Pan Zhang Liu-Chi Chen You-Wei Si Xi-Yao Wan Can Li Ren-He Wang Yu Tian Ziding Zhang Chang-Fu Tian 《The ISME journal》2023,17(3):417
Migration from rhizosphere to rhizoplane is a key selecting process in root microbiome assembly, but not fully understood. Rhizobiales members are overrepresented in the core root microbiome of terrestrial plants, and here we report a genome-wide transposon-sequencing of rhizoplane fitness genes of beneficial Sinorhizobium fredii on wild soybean, cultivated soybean, rice, and maize. There were few genes involved in broad-host-range rhizoplane colonization. The fadL mutant lacking a fatty acid transporter exhibited high colonization rates, while mutations in exoFQP (encoding membrane proteins directing exopolysaccharide polymerization and secretion), but not those in exo genes essential for exopolysaccharide biosynthesis, led to severely impaired colonization rates. This variation was not explainable by their rhizosphere and rhizoplane survivability, and associated biofilm and exopolysaccharide production, but consistent with their migration ability toward rhizoplane, and associated surface motility and the mixture of quorum-sensing AHLs (N-acylated-L-homoserine lactones). Genetics and physiology evidences suggested that FadL mediated long-chain AHL uptake while ExoF mediated the secretion of short-chain AHLs which negatively affected long-chain AHL biosynthesis. The fadL and exoF mutants had elevated and depleted extracellular long-chain AHLs, respectively. A synthetic mixture of long-chain AHLs mimicking that of the fadL mutant can improve rhizobial surface motility. When this AHL mixture was spotted into rhizosphere, the migration toward roots and rhizoplane colonization of S. fredii were enhanced in a diffusible way. This work adds novel parts managing extracellular AHLs, which modulate bacterial migration toward rhizoplane. The FadL-ExoFQP system is conserved in Alphaproteobacteria and may shape the “home life” of diverse keystone rhizobacteria.Subject terms: Microbial ecology, Functional genomics, Bacterial genetics 相似文献