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991.
Costaria costata is a commercially and industrially important brown alga. In this study, we used next-generation sequencing to determine the complete plastid genome of C. costata. The genome consists of a 129,947 bp circular DNA molecule with an A+T content of 69.13% encoding a standard set of six ribosomal RNA genes, 27 transfer RNA genes, and 137 protein-coding genes with two conserved open reading frames (ORFs). The overall genome structure of C. costata is nearly the same as those of Saccharina japonica and Undaria pinnatifida. The plastid genomes of these three algal species retain a strong conservation of the GTG start codon while infrequently using TGA as a stop codon. In this regard, they differ substantially from the plastid genomes of Ectocarpus siliculosus and Fucus vesiculosus. Analysis of the nucleic acid substitution rates of the Laminariales plastid genes revealed that the petF gene has the highest substitution rate and the petN gene contains no substitution over its complete length. The variation in plastid genes between C. costata and S. japonica is lower than that between C. costata and U. pinnatifida as well as that between U. pinnatifida and S. japonica. Phylogenetic analyses demonstrated that C. costata and U. pinnatifida have a closer genetic relationship. We also identified two gene length mutations caused by the insertion or deletion of repeated sequences, which suggest a mechanism of gene length mutation that may be one of the key explanations for the genetic variation in plastid genomes. 相似文献
992.
Shifang Yu Huicong Huang Gang Deng Zuoting Xie Yincai Ye Ruide Guo Xuejiao Cai Junying Hong Dingliang Qian Xiangjing Zhou Zhihua Tao Bile Chen Qiang Li 《PloS one》2015,10(4)
Platelets play crucial roles in hemostasis, thrombosis, wound healing, inflammation, angiogenesis, and tumor metastases. Because they are anucleated blood cells, platelets lack nuclear DNA, but they do contain mitochondrial DNA, which plays a key role in regulating apoptosis. Recent evidence has suggested that miRNAs are also involved in regulating gene expression and apoptosis in platelets. Our previous study showed that the expression of miR-326 increased visibly when apheresis platelets were stored in vitro. The antiapoptotic Bcl-2 family regulator Bcl-xL has been identified as a putative target of miR-326. In the present study, dual reporter luciferase assays were used to characterize the function of miR-326 in the regulation of the apoptosis of platelet cells. These assays demonstrated that miR-326 bound to the 3′-translated region of Bcl-xL. To directly assess the functional effects of miR-326 expression, levels of Bcl-xL and the apoptotic status of stored apheresis platelets were measured after transfection of miR-326 mimic or inhibitor. Results indicated that miR-326 inhibited Bcl-xL expression and induced apoptosis in stored platelets. Additionally, miR-326 inhibited Bcl-2 protein expression and enhanced Bak expression, possibly through an indirect mechanism, though there was no effect on the expression of Bax. The effect of miR-326 appeared to be limited to apoptosis, with no significant effect on platelet activation. These results provide new insight into the molecular mechanisms affecting differential platelet gene regulation, which may increase understanding of the role of platelet apoptosis in multiple diseases. 相似文献
993.
Ning Chen Yun Liu Yijie Cheng Long Liu Zhe Yan Lixin Tao Xiuhua Guo Yanxia Luo Aoshuang Yan 《PloS one》2015,10(9)
Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation. 相似文献
994.
Yexian Yuan Pingwen Xu Qingyan Jiang Xingcai Cai Tao Wang Wentong Peng Jiajie Sun Canjun Zhu Cha Zhang Dong Yue Zhihui He Jinping Yang Yuxian Zeng Man Du Fenglin Zhang Lucas Ibrahimi Sarah Schaul Yuwei Jiang Jiqiu Wang Jia Sun Qiaoping Wang Liming Liu Songbo Wang Lina Wang Xiaotong Zhu Ping Gao Qianyun Xi Cong Yin Fan Li Guli Xu Yongliang Zhang Gang Shu 《The EMBO journal》2021,40(14)
The authors approached the journal to correct a mistake in the data presented in Appendix␣Fig S3D. The authors state that the mouse images in Appendix␣Fig S3D mistakenly displayed images from Fig 2F and Appendix␣Fig S1F. The images in Appendix␣Fig S3D are herewith corrected. The authors state that this change does not affect the conclusions or the statistics. The source data for these panels have been added to the original publication.The authors note that the following sentence needs to be corrected from: Appendix Figure S3D. Original. Appendix Figure S3D. Corrected. “Interestingly, several well‐established accumulation signatures of succinate, malate, hypoxanthine, and xanthine induced by endurance exercise (Lewis et␣al, 2010) were found to be decreased by endurance exercise (Figs 1D and EV1A–D)”.to“Interestingly, several well‐established accumulation signatures of succinate, malate, hypoxanthine, and xanthine induced by endurance exercise (Lewis et␣al, 2010) were found to be decreased by resistance exercise (Figs 1D and EV1A–D)”.Further, the authors requested to amend the legend of Appendix␣Fig S3R to indicate that the same sample for the iWAT group, “WT+2%AKG” treatment, is shown in Fig 3P. The corrected legend reads: “(R‐S). Representative images (R) and quantification (S) of p‐HSL DAB staining from male OXGR1OEAG mice treated with AKG for 12 weeks (n = 6 per group). The same sample is shown as in Fig 3P ”.The authors regret these errors and any confusion they may have caused. All authors approve of this correction. 相似文献
995.
DNA phosphorylation catalyzed by polynucleotide kinase (PNK) is an indispensable process in the repair, replication, and recombination of nucleic acids. Here, an enzyme-assisted amplification strategy was developed for the ultrasensitive monitoring activity and inhibition of T4 PNK. A hairpin oligonucleotide (hpDNA) was designed as a probe whose stem can be degraded from the 5′ to 3′ direction by lambda exonuclease (λ exo) when its 5′ end is phosphorylated by PNK. So, the 3′ stem and loop part of hpDNA was released as an initiator strand to open a molecular beacon (MB) that was designed as a fluorescence reporter, leading to a fluorescence restoration. Then, the initiator strand was released again by the nicking endonuclease (Nt.BbvCI) to hybridize with another MB, resulting in a cyclic reaction and accumulation of fluorescence signal. Based on enzyme-assisted amplification, PNK activity can be sensitively and rapidly detected with a detection limit of 1.0 × 10−4 U/ml, which is superior to those of most existing approaches. Furthermore, the application of the proposed strategy for screening PNK inhibitors also demonstrated satisfactory results. Therefore, it provided a promising platform for monitoring activity and inhibition of PNK as well as for studying the activity of other nucleases. 相似文献
996.
Lusheng Gu Yi Sheng Yan Chen Hao Chang Yongdeng Zhang Pingping Lv Wei Ji Tao Xu 《Biophysical journal》2014,106(11):2443-2449
Single molecule fitting-based superresolution microscopy achieves sub-diffraction-limit image resolution but suffers from a need for long acquisition times to gather enough molecules. Several methods have recently been developed that analyze high molecule density images but most are only applicable to two dimensions. In this study, we implemented a high-density superresolution localization algorithm based on compressed sensing and a biplane approach that provides three-dimensional information about molecules, achieving super-resolution imaging at higher molecule densities than those achieved using the conventional single molecule fitting method. 相似文献
997.
998.
In this study, the microwave rewarming process of cryopreserved samples with embedded superparamagnetic (SPM) nanoparticles was numerically simulated. The Finite Element Method (FEM) was used to calculate the coupling of the electromagnetic field and the temperature field in a microwave rewarming system composed of a cylindrical resonant cavity, an antenna source, and a frozen sample phantom with temperature-dependent properties. The heat generated by the sample and the nanoparticles inside the electromagnetic field of the microwave cavity was calculated. The dielectric properties of the biological tissues were approximated using the Debye model, which is applicable at different temperatures. The numerical results showed that, during the rewarming process of the sample phantom without nanoparticles, the rewarming rate was 29.45 °C/min and the maximum temperature gradient in the sample was 3.58 °C/mm. If nanoparticles were embedded in the sample, and the cavity power was unchanged, the rewarming rate was 47.76 °C/min and the maximum temperature gradient in the sample was 1.64 °C/mm. In the presence of SPM nanoparticles, the rewarming rate and the maximum temperature gradient were able to reach 20.73 °C/min and 0.68 °C/mm at the end of the rewarming under the optimized cavity power setting, respectively. The ability to change these temperature behaviors may prevent devitrification and would greatly diminish thermal stress during the rewarming process. The results indicate that the rewarming rate and the uniformity of temperature distribution are increased by nanoparticles. This could be because nanoparticles generated heat in the sample homogeneously and the time-dependent parameters of the sample improved after nanoparticles were homogeneously embedded within it. We were thus able to estimate the positive effect of SPM nanoparticles on microwave rewarming of cryopreserved samples. 相似文献
999.
During the early vertebrate body plan formation, convergent extension (CE) of dorsal mesoderm and neurectoderm is coordinated by the evolutionarily conserved non-canonical Wnt/PCP signaling. Disheveled (Dvl), a key mediator of Wnt/PCP signaling, is essential for the medial–lateral polarity formation in the cells undergoing convergent extension movements. NEDD4L, a highly conserved HECT type E3 ligase, has been reported to regulate the stability of multiple substrates including Dvl2. Here we demonstrate that NEDD4L is required for the cellular polarity formation and convergent extension in the early Xenopus embryos. Depletion of NEDD4L in early Xenopus embryos results in the loss of mediolateral polarity of the convergent-extending mesoderm cells and the shortened body axis, resembling those defects caused by the disruption of non-canonical Wnt signaling. Depletion of xNEDD4L also blocks the elongation of the animal explants in response to endogenous mesoderm inducing signals and partially compromises the expression of Brachyury. Importantly, reducing Dvl2 expression can largely rescue the cellular polarity and convergent extension defects in NEDD4L-depleted embryos and explants. Together with the data that NEDD4L reduces Dvl2 protein expression in the frog embryos, our findings suggest that regulation of Dvl protein levels by NEDD4L is essential for convergent extension during early Xenopus embryogenesis. 相似文献
1000.
Tao Pan Zhilong Wang Jian-He Xu Zhenqiang Wu Hanshi Qi 《Applied microbiology and biotechnology》2010,85(6):1789-1796
Extractive microbial fermentation for production of lipase by Serratia marcescens ECU1010 has been carried out in cloud point system. The cloud point system is composed of mixture nonionic surfactants with
a ratio of Triton X-114 to Triton X-45 4:1 in aqueous solution. The lipase prefers to partition into the surfactant rich phase
(coacervate phase) whereas the cells and other hydrophilic proteins retain in the dilute phase of cloud point system. Thus,
a concentration factor 4.2-fold and a purification factor 1.3-fold of the lipase have been achieved in the extractive fermentation
process. This is the first report about extractive fermentation of proteins in cloud point system. 相似文献