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Guodong Yang Yuanyuan Li Binjiang Wu Kaiyue Zhang Lei Gao Chengchao Zheng 《植物学报(英文版)》2019,61(11):1128-1133
Micro RNAs(mi RNAs) are vital regulators that repress gene expression in the cytoplasm in two main ways: m RNA degradation and translational inhibition. Several animal studies have shown that mi RNAs also target promoters, thereby activating expression.Whether this mi RNA action also occurs in plants is unknown. In this study, we demonstrated that several mi RNAs regulate target promoters in Arabidopsis thaliana. For example, mi R5658 was predominantly present in the nucleus and activated the expression of AT3 G25290 directly by binding to its promoter. Our observations suggest that this mode of action may be a general feature of plant mi RNAs, and thus provide insight into the vital roles of plant mi RNAs in the nucleus. 相似文献
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ZHENG LianBin LI YongLan XI HuanJiu YU KeLi LU ShunHua SHI Rui WEN YouFeng BAO JingPing ZHANG XingHua LI YuLing REN Fu XU GuoChang 《中国科学:生命科学英文版》2015,58(2):215-217,1,3
<正>Dear Editor,Shortly after initiating the"Physical Anthropological Research on Han Chinese"research project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable 相似文献
215.
Plant Ecology - There is increasing evidence that climate change and nutrient fluctuations can affect the invasion of alien plants. However, most studies have been performed in pairwise experiments... 相似文献
216.
The Golgi-localized, γ-ear-containing, ARF binding proteins (GGAs) are a highly conserved family of monomeric clathrin adaptor proteins implicated in clathrin-mediated protein sorting between the trans-Golgi network and endosomes. GGA RNAi knockdowns in Drosophila have resulted in conflicting data concerning whether the Drosophila GGA (dGGA) is essential. The goal of this study was to define the null phenotype for the unique Drosophila GGA. We describe two independently derived dGGA mutations. Neither allele expresses detectable dGGA protein. Homozygous and hemizygous flies with each allele are viable and fertile. In contrast to a previous report using RNAi knockdown, GGA mutant flies show no evidence of age-dependent retinal degeneration or cathepsin missorting. Our results demonstrate that several of the previous RNAi knockdown phenotypes were the result of off-target effects. However, GGA null flies are hypersensitive to dietary chloroquine and to starvation, implicating GGA in lysosomal function and autophagy. 相似文献
217.
Xuefei Zhang Shiyao Sui Lingling Wang Haixia Li Lei Zhang Shouping Xu Xiulan Zheng 《Journal of cellular physiology》2020,235(4):3425-3437
Glutathione peroxidase 4 (GPX4) has been confirmed to inhibit ferroptosis in cancer cells, however, whether GPX4 serves as an oncogene is not clear. In this study, the expression of GPX4 and its influence to survival of patients with cancer were analyzed via public databases. Furthermore, the epigenetic regulation of GPX4 and the relation between GPX4 and chemoresistance of different anticancer drugs was also detected. Most importantly, cytological assays were performed to investigate the function of GPX4 in cancer cells. The results showed that GPX4 was higher expressed in cancer tissues than normal and was negatively associated with prognosis of patients. Furthermore, at upstream of GPX4 there was low DNA methylation sites and enhanced level of H3K4me3 and H3K27ac, indicating that high level of GPX4 in cancer may resulted from epigenetic regulation. Moreover, GPX4 was positively related to chemoresistance of anticancer drugs L-685458, lapatinib, palbociclib, and topotecan. In addition, GPX4 may potentially be involved in translation of protein, mitochondrial respiratory chain complex I assembly, electron transport oxidative phosphorylation, nonalcoholic fatty liver disease, and metabolic pathways. Finally, we detected that GPX4 inhibited ferroptosis in cancer cells, the inhibition of GPX4 via RSL3 could enhance the anticancer effect of cisplatin in vitro and in vivo. In conclusion, GPX4 acts as an oncogene and inhibits ferroptosis in cancer cells, the anticancer effect of cisplatin can be enhanced by GPX4 inhibition. 相似文献
218.
Peiyu Liu Yan Liu Xiang Zhao Andrew P. Roberts Heng Zhang Yue Zheng Fuxian Wang Lushan Wang Nicolas Menguy Yongxin Pan Jinhua Li 《Environmental microbiology》2021,23(2):1115-1129
Magnetotactic bacteria (MTB) are diverse prokaryotes that produce magnetic nanocrystals within intracellular membranes (magnetosomes). Here, we present a large-scale analysis of diversity and magnetosome biomineralization in modern magnetotactic cocci, which are the most abundant MTB morphotypes in nature. Nineteen novel magnetotactic cocci species are identified phylogenetically and structurally at the single-cell level. Phylogenetic analysis demonstrates that the cocci cluster into an independent branch from other Alphaproteobacteria MTB, that is, within the Etaproteobacteria class in the Proteobacteria phylum. Statistical analysis reveals species-specific biomineralization of magnetosomal magnetite morphologies. This further confirms that magnetosome biomineralization is controlled strictly by the MTB cell and differs among species or strains. The post-mortem remains of MTB are often preserved as magnetofossils within sediments or sedimentary rocks, yet paleobiological and geological interpretation of their fossil record remains challenging. Our results indicate that magnetofossil morphology could be a promising proxy for retrieving paleobiological information about ancient MTB. 相似文献
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Shan Gao Michaela C. Strüder‐Kypke Khaled A. S. Al‐Rasheid Xiaofeng Lin Weibo Song 《Zoologica scripta》2010,39(3):305-313
Gao, S., Strüder‐Kypke, M.C., Al‐Rasheid, K.A.S., Lin, X. & Song, W. (2010). Molecular phylogeny of three ambiguous ciliate genera: Kentrophoros, Trachelolophos and Trachelotractus (Alveolata, Ciliophora).—Zoologica Scripta, 39, 305–313. Very few molecular studies on the phylogeny of the karyorelictean ciliates have been carried out because data of this highly ambiguous group are extremely scarce. In the present study, we sequenced the small subunit ribosomal RNA genes of three morphospecies representing two karyorelictean genera, Kentrophoros, Trachelolophos, and one haptorid, Trachelotractus, isolated from the South and East China Seas. The phylogenetic trees constructed using Bayesian inference, maximum likelihood, maximum parsimony and neighbor‐joining methods yielded essentially similar topologies. The class Karyorelictea is depicted as a monophyletic clade, closely related to the class Heterotrichea. The generic concept of the family Trachelocercidae is confirmed by the clustering of Trachelolophos and Tracheloraphis with high bootstrap support; nevertheless, the order Loxodida is paraphyletic. The transfer of the morphotype Trachelocerca entzi Kahl, 1927 to the class Litostomatea and into the new haptorid genus Trachelotractus, as suggested by previous researchers based on morphological studies, is consistently supported by our molecular analyses. In addition, the poorly known species Parduczia orbis occupies a well‐supported position basal to the Geleia clade, justifying the separation of these genera from one another. 相似文献