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141.
Shen-Ying Zhang Nathaniel E. Clark Catherine A. Freije Elodie Pauwels Allison J. Taggart Satoshi Okada Hanna Mandel Paula Garcia Michael J. Ciancanelli Anat Biran Fabien G. Lafaille Miyuki Tsumura Aurélie Cobat Jingchuan Luo Stefano Volpi Bastian Zimmer Sonoko Sakata Alexandra Dinis Jean-Laurent Casanova 《Cell》2018,172(5):952-965.e18
142.
Pot-grown peanut plants (Arachis hypogaea L.) cv. Yue-You No. 551–116 at five-leaf-stage were treated with 0, 266 or 532 ppm growth retardant PP333 aqueous solution as a soildrench and liquid spray to the whole shoot, smeared on the stems or fully developed leaves. Forty days after treatment, growth rate of main stem and transpiratory rate were measured andthe ultrastructures of leaf and chloroplast were also observed under electron microscope. The results obtained are as follows: 1. PP333 resulted in reduction of stem elongation and dryweight of shoot, but there was no influence or even slight enhancement with the dry weight of root, thus, the root: stem ratio was increased. By applicating PP333, transpiratory rate was lessthan that of the control, but the water storage cells in treated leaves were significantly larger. These anatomical and physiological characteristics of treated plant are an advantage in tolerating the drought stress. 2. Compared with the control, PP333 caused the epidermal cellsize smaller and reduced the number of grana lamella and stroma lamella, so development of chloroplast was inhibited. 3. Significant retardation occurred when PP333 was applied to soilas compared with that applied to the shoot. Among shoot applications, the stem is more effective at reducing stem elongation than that to the leaf. Based on the results mentioned above, authors suggest that the most effective method of PP333. application for peanut is soil drench. 相似文献
143.
144.
Computational prediction of RNA‐binding residues is helpful in uncovering the mechanisms underlying protein‐RNA interactions. Traditional algorithms individually applied feature‐ or template‐based prediction strategy to recognize these crucial residues, which could restrict their predictive power. To improve RNA‐binding residue prediction, herein we propose the first integrative algorithm termed RBRDetector (RNA‐Binding Residue Detector) by combining these two strategies. We developed a feature‐based approach that is an ensemble learning predictor comprising multiple structure‐based classifiers, in which well‐defined evolutionary and structural features in conjunction with sequential or structural microenvironment were used as the inputs of support vector machines. Meanwhile, we constructed a template‐based predictor to recognize the putative RNA‐binding regions by structurally aligning the query protein to the RNA‐binding proteins with known structures. The final RBRDetector algorithm is an ingenious fusion of our feature‐ and template‐based approaches based on a piecewise function. By validating our predictors with diverse types of structural data, including bound and unbound structures, native and simulated structures, and protein structures binding to different RNA functional groups, we consistently demonstrated that RBRDetector not only had clear advantages over its component methods, but also significantly outperformed the current state‐of‐the‐art algorithms. Nevertheless, the major limitation of our algorithm is that it performed relatively well on DNA‐binding proteins and thus incorrectly predicted the DNA‐binding regions as RNA‐binding interfaces. Finally, we implemented the RBRDetector algorithm as a user‐friendly web server, which is freely accessible at http://ibi.hzau.edu.cn/rbrdetector . Proteins 2014; 82:2455–2471. © 2014 Wiley Periodicals, Inc. 相似文献
145.
T.‐J. Qin J. Zhou Y. Sun H. Müller‐Schrer F.‐L. Luo B.‐C. Dong H.‐L. Li F.‐H. Yu 《Plant biology (Stuttgart, Germany)》2020,22(4):591-599
- Highly biodiversity communities have been shown to better resist plant invasions through complementarity effects. Species richness (SR) is a widely used biodiversity metric but lacks explanatory power when there are only a few species. Communities with low SR can have a wide variety of phylogenetic diversities (PD), which might allow for a better prediction of invasibility.
- We assessed the effect of diversity reduction of a wetland community assemblage typical of the Beijing area on biotic resistance to invasion of the exotic weed Alternanthera philoxeroides and compared the reduction in SR and PD in predicting community invasibility.
- The eight studied resident species performed similarly when grown alone and when grown in eight‐species communities together with the invasive A. philoxeroides. Variation partitioning showed that PD contributed more to variation in both A. philoxeroides traits and community indicators than SR. All A. philoxeroides traits and community indicators, except for evenness index, showed a linear relationship with PD. However, only stem length of A. philoxeroides differed between the one‐ and two‐species treatments, and the diversity index of the communities differed between the one‐ and two‐species treatments and between the one‐ and four‐species treatments.
- Our results showed that in natural or semi‐natural wetlands with relatively low SR, PD may be a better predictor of invasibility than SR. When designing management strategies for mitigating A. philoxeroides invasion, deliberately raising PD is expected to be more efficient than simply increasing species number.
146.
147.
Si‐Min Yan Hu Li Qing Shu Wei‐Jun Wu Xue‐Mei Luo Lei Lu 《Cell biology international》2020,44(4):1009-1019
Heart failure preceded by pathological cardiac hypertrophy is a leading cause of death. Long noncoding RNA small nucleolar RNA host gene 1 (SNHG1) was reported to inhibit cardiomyocytes apoptosis, but the role and underlying mechanism of SNHG1 in pathological cardiac hypertrophy have not yet been understood. This study was designed to investigate the role and molecular mechanism of SNHG1 in regulating cardiac hypertrophy. We found that SNHG1 was upregulated during cardiac hypertrophy both in vivo (transverse aortic constriction treatment) and in vitro (phenylephrine [PE] treatment). SNHG1 overexpression attenuated the cardiomyocytes hypertrophy induced by PE, while SNHG1 inhibition promoted hypertrophic response of cardiomyocytes. Furthermore, SNHG1 and high‐mobility group AT‐hook 1 (HMGA1) were confirmed to be targets of miR‐15a‐5p. SNHG1 promoted HMGA1 expression by sponging miR‐15a‐5p, eventually attenuating cardiomyocytes hypertrophy. There data revealed a novel protective mechanism of SNHG1 in cardiomyocytes hypertrophy. Thus, targeting of SNHG1‐related pathway may be therapeutically harnessed to treat cardiac hypertrophy. 相似文献
148.
Jingru Sun Xiao Zhang Chuanjian Cao Xindi Mei Ningning Wang Suli Yan Shixiang Zong Youqing Luo Haijun Yang Yingbai Shen 《PloS one》2014,9(4)
Herbivore-induced plant volatiles (HIPVs) are important compounds to prim neighboring undamaged plants; however, the mechanism for this priming process remains unclear. To reveal metabolic changes in plants exposed to HIPVs, metabolism of leaves and roots of Ammopiptanthus mongolicus seedlings exposed to HIPVs released from conspecific plants infested with larvae of Orgyia ericae were analyzed together with control and infested seedlings using nuclear magnetic resonance (NMR)-based metabolic technology and multi variate data analysis. Results presented showed that HIPVs exposure led to similar but specific metabolic changes compared with those induced by infestation in both leaves and roots. Furthermore, both HIPVs exposure and herbivore attack resulted in metabolic changes involving a series of primary and secondary metabolites in both leaves and roots. Taken together, these results suggested that priming of yet-damaged plants may be achieved by reconfiguring metabolic pathways in leaves and roots to make similar concentrations for all metabolites as those in seedlings infested. Therefore, we propose that improved readiness of defense induction of primed plants toward subsequent herbivore attack may be based on the similar metabolic profiling induced by HIPVs exposure as those caused by herbivore. 相似文献
149.
Objectives
Although many studies about breast contrast-enhanced ultrasound had been conducted, clear diagnostic criteria for evaluating enhancement patterns are still lacking. This study aims to identify significant indicators for breast contrast-enhanced ultrasound and to establish an initial scoring system.Materials and Methods
Totally 839 patients were included in the study. This study was divided into two parts. 364 patients were included in part 1 while 475 in part 2. Conventional ultrasound and contrast-enhanced ultrasound were used to examine each lesion. Only the cases in part 2 were also examined by elastography. In part 1, Logistic regression analysis was performed to predict significant variables. A 5-point scoring system was developed based on the results. In part 2, the scoring system was used to evaluate all the breast lesions. To evaluate the diagnostic efficacy of the new scoring system, it was compared with the system established for elastography and conventional ultrasound (BI-RADS).Results
Three independent variables, namely, lesion scope, margin, and shape were selected in the final step of the logistic regression analysis in part 1. In part 2, the area under the ROC (receiver operating characteristic) curve for the contrast-enhanced scoring system was 0.912. The difference in the diagnostic capabilities of the contrast-enhanced scoring system and elastography was not statistically significant (P = 0.17). The difference in the diagnostic capabilities of the contrast-enhanced scoring system and BI-RADS was statistically significant (P<0.001).Conclusions
The contrast-enhanced patterns of benign and malignant breast tumors are different. The application of a 5-point scoring system for contrast-enhanced ultrasound is clinically promising. 相似文献150.