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171.
172.
Chung-Wei Chiang Wen-Chi Shu Jun Wan Beth A. Weaver Meyer B. Jackson 《The Journal of general physiology》2021,153(5)
Spontaneous exocytosis of single synaptic vesicles generates miniature synaptic currents, which provide a window into the dynamic control of synaptic transmission. To resolve the impact of different factors on the dynamics and variability of synaptic transmission, we recorded miniature excitatory postsynaptic currents (mEPSCs) from cocultures of mouse hippocampal neurons with HEK cells expressing the postsynaptic proteins GluA2, neuroligin 1, PSD-95, and stargazin. Synapses between neurons and these heterologous cells have a molecularly defined postsynaptic apparatus, while the compact morphology of HEK cells eliminates the distorting effect of dendritic filtering. HEK cells in coculture produced mEPSCs with a higher frequency, larger amplitude, and more rapid rise and decay than neurons from the same culture. However, mEPSC area indicated that nerve terminals in synapses with both neurons and HEK cells release similar populations of vesicles. Modulation by the glutamate receptor ligand aniracetam revealed receptor contributions to mEPSC shape. Dendritic cable effects account for the slower mEPSC rise in neurons, whereas the slower decay also depends on other factors. Lastly, expression of synaptobrevin transmembrane domain mutants in neurons slowed the rise of HEK cell mEPSCs, thus revealing the impact of synaptic fusion pores. In summary, we show that cocultures of neurons with heterologous cells provide a geometrically simplified and molecularly defined system to investigate the time course of synaptic transmission and to resolve the contribution of vesicles, fusion pores, dendrites, and receptors to this process. 相似文献
173.
Yi-Fei Lu Xiao-Feng Jin Hiroshi Ikeda Okihito Yano Carmen Benítez-Benítez Wei-Jie Chen Yong-Di Liu Pedro Jiménez-Mejías Ming-Jian Yu 《植物分类学报:英文版》2021,59(4):668-686
Carex sect. Confertiflorae s.l. is a medium-sized species group (ca. 40 species) with its center of diversity in E Asia (China and Japan). According to morphological traits, the section has been proposed to split into two sections (sects. Confertiflorae sensu Ohwi and Molliculae Ohwi) up to five different ones (sects. Confertiflorae s.s., Molliculae, Dispalatae Ohwi, Ischnostachyae Ohwi, and Alliiformes Akiyama). Recent phylogenetic reconstructions showed Confertiflorae s.l. not to be monophyletic, as species traditionally considered part of it were found to belong to other clades, whereas species traditionally ascribed to other sections were nested within it. In this study, we investigated the phylogenetic structure, morphological affinities, and biogeographic history of sect. Confertiflorae s.l. We employed a taxon-based approach to explore the morphological affinities of the species considered in sect. Confertiflorae and compared the micromorphology of the nutlets of almost all the taxa using SEM. We included 40 samples representing 31 species/subspecies of sect. Confertiflorae s.l. and used two nuclear (ETS and ITS) and three plastid (trnL-F, matK, and rpl32-trnL UAG) molecular markers to reconstruct the phylogeny of the group. The phylogenetic analyses confirmed the polyphyly of sect. Confertiflorae s.l., whose representatives were found within five distinct clades. From these, two clades, sect. Confertiflorae and sect. Molliculae, were found to be closely related and contained the majority of the species. The composition of the two clades agreed with the morphological structure of the group, and we confirmed an exclusive combination of features (namely color of basal sheaths, presence of bract sheath, peduncle of lowest spike, inflorescence sex distribution, shape of pistillate glume apex, and color and veins of utricle, among others) characterizing each of the two clades. The origin of the two clades was found to be in the early Pliocene; however, the majority of the diversification events within each clade took place during the Pleistocene. This illustrates that although Asia has been regarded as having little potential ecological space for Carex to diversify due to its climate stability, groups of sedges sub-endemic from that area may have a fairly recent origin related to glaciations. We proposed the rearrangement of sect. Confertiflorae as previously conceived as three independent sections: the monotypic Alliiformes, sect. Molliculae, and sect. Paludosae. 相似文献
174.
José I. Márquez-Corro Santiago Martín-Bravo Pedro Jiménez-Mejías rew L. Hipp Daniel Spalink Robert F. C. Naczi Eric H. Roalson Modesto Luceño Marcial Escudero 《植物分类学报:英文版》2021,59(4):776-790
Changes in holocentric chromosome number due to fission and fusion have direct and immediate effects on genome structure and recombination rates. These, in turn, may influence ecology and evolutionary trajectories profoundly. Sedges of the genus Carex (Cyperaceae) comprise ca. 2000 species with holocentric chromosomes. The genus exhibits a phenomenal range in the chromosome number (2n = 10 − 132) with almost not polyploidy. In this study, we integrated the most comprehensive cytogenetic and phylogenetic data for sedges with associated climatic and morphological data to investigate the hypothesis that high recombination rates are selected when evolutionary innovation is required, using chromosome number evolution as a proxy for recombination rate. We evaluated Ornstein–Uhlenbeck models to infer shifts in chromosome number equilibrium and selective regime. We also tested the relationship between chromosome number and diversification rates. Our analyses demonstrate significant correlations between morphology and climatic niche and chromosome number in Carex. Nevertheless, the amount of chromosomal variation that we are able to explain is very small. We recognized a large number of shifts in mean chromosome number, but a significantly lower number in climatic niche and morphology. We also detected a peak in diversification rates near intermediate recombination rates. In combination, these analyses point toward the importance of chromosome evolution to the evolutionary history of Carex. Our work suggests that the effect of chromosome evolution on recombination rates, not just on reproductive isolation, may be central to the evolutionary history of sedges. 相似文献
175.
Carmen Benítez-Benítez Santiago Martín-Bravo Charlotte S. Bjorå Sebastian Gebauer rew L. Hipp Matthias H. Hoffmann Modesto Luceño Tyril M. Pedersen Anton Reznicek Eric Roalson Polina Volkova Okihito Yano Daniel Spalink Pedro Jiménez-Mejías 《植物分类学报:英文版》2021,59(4):642-667
Carex section Phacocystis (Cyperaceae) is one of the most diverse and taxonomically complex groups of sedges (between 116 and 147 species), with a worldwide distribution in a wide array of biomes. It has a very complicated taxonomic history, with numerous disagreements among different treatments. We studied the biogeography and niche evolution in a phylogenetic framework to unveil the relative contribution of geographical and ecological drivers to diversification of the group. We used a large species sampling of the section (82% of extant species) to build a phylogeny based on four DNA regions, constrained with a phylogenomic HybSeq tree and dated with six fossil calibrations. Our phylogenetic results recovered section Phacocystis s.s. (core Phacocystis) as sister to section Praelongae. Ancestral area reconstruction points toward the N Pacific as the cradle for the crown diversification of section Phacocystis during the Middle Miocene. Wide distributions were recurrently inferred across deep nodes. Large Northern Hemisphere lineages with geographical congruence were retrieved, pointing toward the importance of allopatric divergence at deep phylogenetic levels, whereas within-area speciation emerges as the predominant pattern at shallow phylogenetic level. The Southern Hemisphere (Neotropics, SW Pacific) was colonized several times from the Northern Hemisphere. The global expansion of Carex section Phacocystis did not entail major ecological changes along the inner branches of the phylogeny. Nevertheless, ecological differentiation seems to gain importance toward recent times. 相似文献
176.
Wan Qiangyou Kong Deping Liu Qian Guo Shumin Wang Chenchen Zhao Yan Ke Zun-Ji Yu Ying 《中国科学:生命科学英文版》2021,64(7):1068-1076
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit prostaglandin (PG) formation by targeting cyclooxygenase (COX) 1 and 2.Long-term use of NSAIDs that selectively inhibit COX2 increases the risk for thrombotic events,cardiac failure,and hypertension.However,the underlying mechanisms remain unclear.In this study,COX1- and COX2-deficient rats were created via Cas9/RNA-mediated gene targeting.DNA genotyping and Western blot analysis confirmed successful generation of COX1~(-/-)and COX2~(-/-)rats.Adult COX1~(-/-)rats grew normally,while more than 70%of COX2~(-/-)rats after wean died within 2 months.Echocardiography showed markedly reduced left ventricular ejection fraction and fractional shortening in adult COX2~(-/-)rats compared to those in wildtype (WT) controls.Histological analysis revealed accumulation of inflammatory cells and severe interstitial and perivascular fibrosis in COX2~(-/-)cardiac tissues.Moreover,cardiac ATP and acetyl-Co A production was dramatically decreased in COX2~(-/-)rats.Consistently,the expression of genes related to mitochondrial oxidation,such as those that encode for subunits of pyruvate dehydrogenase complex and acyl Co A dehydrogenases,were downregulated,while glycolytic hexokinase 1 (HK1) was upregulated in COX2~(-/-)heart tissues.These observations indicate that COX2-deficient rats developed spontaneously heart failure,likely as a result of dysregulated cardiac energy metabolism. 相似文献
177.
Castañeda-Pérez Eduardo Jiménez-Morales Karina Castellanos-Ruelas Arturo Chel-Guerrero Luis Betancur-Ancona David 《International journal of peptide research and therapeutics》2021,27(3):1979-1988
International Journal of Peptide Research and Therapeutics - Characterized by uncontrolled, long-term high blood sugar levels, diabetes mellitus affects ever increasing numbers of people worldwide.... 相似文献
178.
Xiu-Ping Zhang Qinjunjie Chen Qu Liu Yang Wang Fei Wang Zhi-Ming Zhao Guo-Dong Zhao Wan Yee Lau Yu-Zhen Gao Rong Liu 《Journal of cellular and molecular medicine》2021,25(12):5615-5627
Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with aggressive biological behaviour. Its rapid proliferation and tumour growth require reprogramming of glucose metabolism or the Warburg effect. However, the association between glycolysis-related genes with clinical features and prognosis of PDAC is still unknown. Here, we used the meta-analysis to correlate the hazard ratios (HR) of 106 glycolysis genes from MSigDB by the cox proportional hazards regression analysis in 6 clinical data sets of PDAC patients to form a training cohort, and a single group of PDAC patients from the TCGA, ICGC, Arrayexpress and GEO databases to form the validation cohort. Then, a glycolysis-related prognosis (GRP) score based on 29 glycolysis prognostic genes was established in 757 PDAC patients from the training composite cohort and validated in 267 ICGC-CA validation cohort (all P < .05). In addition, including PADC, the prognostic value was also confirmed in other 7 out of 30 pan-cancer cohorts. The GRP score was significantly related to specific metabolism pathways, immune genes and immune cells in the patients with PADC (all P < .05). Finally, by combining with immune cells, the GRP score also well-predicted the chemosensitivity of patients with PADC in the TCGA cohort (AUC = 0.709). In conclusion, this study developed a GRP score for patients with PDAC in predicting prognosis and chemosensitivity for PDAC. 相似文献
179.
Cui Liu Qian He Linlin Zeng Ling Shen Qiaomei Luo Wentao Zhang Xia Zhou Jun Wan 《化学与生物多样性》2021,18(12):e2100705
Emerging evidence suggests that a high-fat diet (HFD) can influence endoplasmic reticulum (ER) stress and gut microbiota. Crataegi Fructus is a traditional Chinese herb widely used in formulas for dyspepsia, with Dashanzha Pill composed of raw Crataegi Fructus (DR) being a representative drug. Processing products of Crataegi Fructus, however, have a stronger pro-digestive effect, and we hypothesized that Dashanzha Pill composed of charred Crataegi Fructus (DC) is more effective. We found that the contents of glucose 1-phosphate and luteolin in DR and DC were substantially different via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry. DC outperformed DR in improving histopathological changes, increasing gastrin and motilin, and decreasing vasoactive intestinal peptides in rats with HFD induced dyspepsia. Fecal microbiota analysis revealed that DC could restore the disturbed intestinal microbiota composition, including that of Bacteroides, Akkermansia, and Intestinimonas to normal levels. Furthermore, DC significantly reduced the mRNA and protein levels of glucose-regulated protein 78, protein kinase R-like ER kinase, and eukaryotic initiation factor 2α. Taken together, DC outperformed DR in relieving dyspepsia by regulating gut microbiota and alleviating ER stress. 相似文献
180.
Xi Tian Wen-Hao Xu Aihetaimujiang Anwaier Hong-Kai Wang Fang-Ning Wan Da-Long Cao Wen-Jie Luo Guo-Hai Shi Yuan-Yuan Qu Hai-Liang Zhang Ding-Wei Ye 《Journal of cellular and molecular medicine》2021,25(8):3898-3911
This study aims to construct a robust prognostic model for adult adrenocortical carcinoma (ACC) by large-scale multiomics analysis and real-world data. The RPPA data, gene expression profiles and clinical information of adult ACC patients were obtained from The Cancer Proteome Atlas (TCPA), Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Integrated prognosis-related proteins (IPRPs) model was constructed. Immunohistochemistry was used to validate the prognostic value of the IPRPs model in Fudan University Shanghai Cancer Center (FUSCC) cohort. 76 ACC cases from TCGA and 22 ACC cases from GSE10927 in NCBI’s GEO database with full data for clinical information and gene expression were utilized to validate the effectiveness of the IPRPs model. Higher FASN (P = .039), FIBRONECTIN (P < .001), TFRC (P < .001), TSC1 (P < .001) expression indicated significantly worse overall survival for adult ACC patients. Risk assessment suggested significantly a strong predictive capacity of IPRPs model for poor overall survival (P < .05). IPRPs model showed a little stronger ability for predicting prognosis than Ki-67 protein in FUSCC cohort (P = .003, HR = 3.947; P = .005, HR = 3.787). In external validation of IPRPs model using gene expression data, IPRPs model showed strong ability for predicting prognosis in TCGA cohort (P = .005, HR = 3.061) and it exhibited best ability for predicting prognosis in GSE10927 cohort (P = .0898, HR = 2.318). This research constructed IPRPs model for predicting adult ACC patients’ prognosis using proteomic data, gene expression data and real-world data and this prognostic model showed stronger predictive value than other biomarkers (Ki-67, Beta-catenin, etc) in multi-cohorts. 相似文献