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181.
182.
Pan Chen Ying Miao PuJun Yan Xiao Jie Wang ChunXia Jiang Yi Lei 《Journal of cellular physiology》2019,234(12):21915-21924
Diabetic retinopathy (DR) remains the leading cause of blindness in adults with diabetes mellitus. Numerous microRNAs (miRNAs) have been identified to modulate the pathogenesis of DR. The main purpose of this study was to evaluate the potential roles of miR-455-5p in high glucose (HG)-treated retinal pigment epithelial (RPE) cells and underlying mechanisms. Our present investigation discovered that the expression of miR-455-5p was apparently downregulated in ARPE-19 cells stimulated with HG. In addition, forced expression of miR-455-5p markedly enhanced cell viability and restrained HG-induced apoptosis accompanied by decreased BCL2-associated X protein (Bax)/B-cell leukemia/lymphoma 2 (Bcl-2) ratio and expression of apoptotic marker cleaved caspase-3 during HG challenged. Subsequently, augmentation of miR-455-5p remarkably alleviated HG-triggered oxidative stress injury as reflected by decreased the production of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) content as well as NADPH oxidase 4 expression, concomitant with enhanced the activities of superoxide dismutase, catalase, and GPX stimulated with HG. Furthermore, enforced expression of miR-455-5p effectively ameliorated HG-stimulated inflammatory response as exemplified by repressing the secretion of inflammatory cytokines interleukin 1β (IL-1β), IL-6, and tumour necrosis factor-α in ARPE-19 cells challenged by HG. Most importantly, we successfully identified suppressor of cytokine signaling 3 (SOCS3) as a direct target gene of miR-455-5p, and miR-455-5p negatively regulated the expression of SOCS3. Mechanistically, restoration of SOCS3 abrogated the beneficial effects of miR-455-5p on apoptosis, accumulation of ROS, and inflammatory factors production in response to HG. Taken together, these findings demonstrated that miR-455-5p relieved HG-induced damage through repressing apoptosis, oxidant stress, and inflammatory response by targeting SOCS3. The study gives evidence that miR-455-5p may serve as a new potential therapeutic agent for DR treatment. 相似文献
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Luoyang Li Xingliang Zhang Christian B. Skovsted Hao Yun Bing Pan Guoxiang Li 《Palaeontology》2019,62(4):515-532
Hyoliths were among the earliest biomineralizing metazoans in Palaeozoic marine environments. They have been known for two centuries and widely assigned to lophotrochozoans. However, their origin and relationships with modern lophotrochozoan clades have been a longstanding palaeontological controversy. Here, we provide broad microstructural data from hyolith conchs and opercula from the lower Cambrian Xinji Formation of North China, including two hyolithid genera and four orthothecid genera as well as unidentified opercula. Results show that most hyolith conchs contain a distinct aragonitic lamellar layer that is composed of foliated aragonite, except in the orthothecid New taxon 1 that has a crossed foliated lamellar microstructure. Opercula are mostly composed of foliated aragonite and occasionally foliated calcite. These blade or lath‐like microstructural fabrics coincide well with biomineralization of Cambrian molluscs rather than lophophorates, as exemplified by the Cambrian members of the tommotiid‐brachiopod linage. Accordingly, we propose that hyoliths and molluscs might have inherited their biomineralized skeletons from a non‐mineralized or weakly mineralized common ancestor rather than as a result of convergence. Consequently, from the view of biomineralization, the homologous shell microstructures in Cambrian hyoliths and molluscs strongly strengthen the phylogenetic links between the two groups. 相似文献
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Changtian Pan Dandan Yang Xiaolin Zhao Chen Jiao Yanqiu Yan Anthony Tumbeh Lamin‐Samu Qiaomei Wang Xiangyang Xu Zhangjun Fei Gang Lu 《Plant, cell & environment》2019,42(4):1205-1221
High temperature (HT) is becoming an increasingly serious factor in limiting crop production with global climate change. During hot seasons, owing to prevailing HT, cultivated tomatoes are prone to exhibiting stigma exsertion, which hampers pollination and causes fruit set failure. However, the underlying regulatory mechanisms of the HT‐induced stigma exsertion remain largely unknown. Here, we demonstrate that stigma exsertion induced by HT in cultivated tomato is caused by more seriously shortened stamens than pistils, which is different from the stigma exsertion observed in wild tomato species. Under the HT condition, the different responses of pectin, sugar, expansin, and cyclin cause cell wall remodelling and differentially localized cell division and selective cell enlargement, which further determine the lengths of stamens and pistils. In addition, auxin and jasmonate (JA) are implicated in regulating cell division and cell expansion in stamens and pistils, and exogenous JA instead of auxin treatment can effectively rescue tomato stigma exsertion through regulating the JA/COI1 signalling pathway. Our findings provide a better understanding of stigma exsertions under the HT condition in tomato and uncover a new function of JA in improving plant abiotic stress tolerance. 相似文献
188.
Liu Siqi Wang Bo Li Xiaojing Pan Jingxian Qian Xuexue Yu Yahui Xu Ping Zhu Jian Xu Xiaofeng 《Plant Cell, Tissue and Organ Culture》2019,137(3):485-494
Plant Cell, Tissue and Organ Culture (PCTOC) - Callus is a remarkable regeneration tissue. The genes correlated with root development can be involved in regulating callus development in higher... 相似文献
189.
Gene expression associated with indicated faster growth of crossbreeding in Sinocyclocheilus grahami
Yuanwei Zhang Wei Fan Xiaofu Pan Xiaoai Wang Wansheng Jiang Kunfeng Yang Junxing Yang 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):944-953
In this study, pure‐breeding and crossbreeding of Sinocyclocheilus grahami were established to test heterosis and expression of growth‐related genes which were examined in the first‐generation (F1). Genetic distances results showed that Muyang river (M) and Sanbaimu reservoir (S) populations had smaller interspecific distances (genetic distance: 0.000) while larger distances were shown to other two populations (0.024 of Jiuzhai vauclusian spring [J] and 0.044 of Chenglong vauclusian spring [C]). Full‐sib families were created by using the Muyang river population as females: MM, MS, MJ and MC. Growth performance had significant differences between each group of F1 hybrids; the fastest growth group was shown in MJ while the slowest was in MS. For growth‐related genes, the fast growth group of MJ hybrids showed significantly higher levels of ghrelin expression in strong expression tissues of the intestine and liver. Among the four combinations, mRNA levels of insulin‐like growth factor I (IGF‐I) were the highest expression in MJ hybrids than others in all tested tissues. Myostatin b and somatostatin1 (SST1) were strongly expressed in the brain and MJ hybrids showed relatively lower expression level. In the muscle, slow growth group of MS hybrids showed extremely higher expression levels of these two genes, especially SST1 gene. In conclusion, associating growth with growth‐related genes expression indicated faster growth of crossbreeding in S. grahami and can make a contribution to commercial fish production in the future. 相似文献
190.
Qi Zhang Shiyuan Wang Yi Pan Dongqing Su Qianzi Lu Yongchun Zuo Lei Yang 《Genomics》2019,111(5):1134-1141
Knowing the comprehensive knowledge about the protein subcellular localization is an important step to understand the function of the proteins. Recent advances in system biology have allowed us to develop more accurate methods for characterizing the proteins at subcellular localization level. In this study, the analysis method was developed to characterize the topological properties and biological properties of the cytoplasmic proteins, inner membrane proteins, outer membrane proteins and periplasmic proteins in Escherichia coli (E. coli). Statistical significant differences were found in all topological properties and biological properties among proteins in different subcellular localizations. In addition, investigation was carried out to analyze the differences in 20 amino acid compositions for four protein categories. We also found that there were significant differences in all of the 20 amino acid compositions. These findings may be helpful for understanding the comprehensive relationship between protein subcellular localization and biological function 相似文献