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201.
Ligand inducible proteins that enable precise and reversible control of nuclear translocation of passenger proteins have broad applications ranging from genetic studies in mammals to therapeutics that target diseases such as cancer and diabetes. One of the drawbacks of the current translocation systems is that the ligands used to control nuclear localization are either toxic or prone to crosstalk with endogenous protein cascades within live animals. We sought to take advantage of salicylic acid (SA), a small molecule that has been extensively used in humans. In plants, SA functions as a hormone that can mediate immunity and is sensed by the nonexpressor of pathogenesis-related (NPR) proteins. Although it is well recognized that nuclear translocation of NPR1 is essential to promoting immunity in plants, the exact subdomain of Arabidopsis thaliana NPR1 (AtNPR1) essential for SA-mediated nuclear translocation is controversial. Here, we utilized the fluorescent protein mCherry as the reporter to investigate the ability of SA to induce nuclear translocation of the full-length NPR1 protein or its C-terminal transactivation (TAD) domain using HEK293 cells as a heterologous system. HEK293 cells lack accessory plant proteins including NPR3/NPR4 and are thus ideally suited for studying the impact of SA-induced changes in NPR1. Our results obtained using a stable expression system show that the TAD of AtNPR1 is sufficient to enable the reversible SA-mediated nuclear translocation of mCherry. Our studies advance a basic understanding of nuclear translocation mediated by the TAD of AtNPR1 and uncover a biotechnological tool for SA-mediated nuclear localization.  相似文献   
202.
cis-4-Amino-L-proline derivatives 1 and 2 derived from quinazolinone and pyrazolo pyrimidone respectively were designed as novel lipid lowering agents. A preliminary in vivo screening indicates that 1b and 2a have moderate triglyceride lowering activity.  相似文献   
203.
It is of interest to evaluate the frequency of premolar extractions during orthodontic treatment in patients reporting to the Saveetha dental hospital in Chennai from 2019-2020. We used the records from 987 patients who underwent orthodontic treatment from June 2019 to March 2020 in a dental hospital for this analysis. Digital case records of patients who underwent therapeutic extractions of premolars were isolated. A sample dataset of 340 case records were selected for this study. Data shows that 34.4% of subjects underwent premolar extractions amongst a total of 987 subjects who underwent orthodontic treatment. 89.4% of patients were Angle''s Class I malocclusion patients, and the rest were Class II patients. However, no premolar extractions were done in Class III patients. Data also shows that 67.1% of subjects underwent all 4 first premolar extractions and 13.2% underwent only upper first premolar extractions. Thus, a significant association was found between Type of Malocclusion and the Type of premolar extractions with p < 0.05. Moreover, only 34.4% of patients underwent premolar extractions and the majority of them underwent all 4 first premolar extractions.  相似文献   
204.
The ability to genotype multiple loci of single cells would be of significant benefit to investigations of cellular processes such as oncogenesis, meiosis, fertilization, and embryogenesis. We report a simple two-step, single-tube protocol for whole-genome amplification (WGA) from single human cells using components of the GenomiPhi V2 DNA Amplification kit. For the first time, we demonstrate reliable generation of 4-7 microg amplified DNA from a single human cell within 4 h with a minimum amount of artifactual DNA synthesis. DNA amplified from single cells was genotyped for 13 heterozygous short tandem repeats (STRs) and 7 heterozygous single nucleotide polymorphisms (SNPs), and the genotyping results were compared with purified genomic DNA. Accuracy of genotyping (percent of single-cell amplifications genotyped accurately for any particular STR or SNP) varied from 37% to 100% (with an average of 80%) for STRs and from 89% to 100% (averaging 94%) for SNPs. We suggest that the method described in this report is suitable for WGA from single cells, the product of which can be subsequently used for many applications, such as preimplantation genetic analysis (PGD).  相似文献   
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Mini-mu derivatives carrying plasmid replicons can be used to clone genesin vivo. This method was adopted to generate phasmid clones which were later screened for their ability of restore nitrofurantoin sensitivity of a nitrofuran-resistant host by eliciting nitroreductase activity. One phasmid-derived clone (pAJ101) resulted in considerable increase in nitroreductase activity when introduced into a nitrofurantoin-resistant mutant ofEscherichia coli with reduced nitroreductase activity. Subsequently, a 1.8 kb fragment obtained from pAJ101 by partial digestion with 5au3A, was subcloned into pUC18 to yield pAJ102. The nitroreductase activity attributable to pAJ102 was capable of reducing both nitrofurantoin and nitrofurazone. The polypeptides encoded by pAJ102 were identified by the minicell method. A large, well-defined band corresponding to 37 kDa and a smaller, less-defined band corresponding to 35 kDa were detected. Tnl000 mutagenesis was used to delineate the coding segment of the 1.8 kb insert of pAJ102. A 0.8 kb stretch of DNA was shown to be part of the nitroreductase gene. The gene was mapped at 19 min on theEscherichia coli linkage map.  相似文献   
208.
InthecourseofrevisingthegenusPrimulaLinn .(Primulaceae)intheHimalayasofIndianre gion ,theauthorscameacrossasetofcollectionsidentifiedasP .involucrataWall.gatheredbythepioneerHimalayantravellers,merelywrittenondeterminavitslipsasP .involucrataWall.formaschiz…  相似文献   
209.
The problem of predicting non-long terminal repeats (LTR) like long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs) from the DNA sequence is still an open problem in bioinformatics. To elevate the quality of annotations of LINES and SINEs an automated tool "RetroPred" was developed. The pipeline allowed rapid and thorough annotation of non-LTR retrotransposons. The non-LTR retrotransposable elements were initially predicted by Pairwise Aligner for Long Sequences (PALS) and Parsimonious Inference of a Library of Elementary Repeats (PILER). Predicted non-LTR elements were automatically classified into LINEs and SINEs using ANN based on the position specific probability matrix (PSPM) generated by Multiple EM for Motif Elicitation (MEME). The ANN model revealed a superior model (accuracy = 78.79 +/- 6.86 %, Q(pred) = 74.734 +/- 17.08 %, sensitivity = 84.48 +/- 6.73 %, specificity = 77.13 +/- 13.39 %) using four-fold cross validation. As proof of principle, we have thoroughly annotated the location of LINEs and SINEs in rice and Arabidopsis genome using the tool and is proved to be very useful with good accuracy. Our tool is accessible at http://www.juit.ac.in/RepeatPred/home.html.  相似文献   
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