Prime editing is a versatile CRISPR/Cas-based precise genome-editing technique for crop breeding. Four new types of prime editors (PEs) named PE6a-d were recently generated using evolved and engineered reverse transcriptase (RT) variants from three different sources. In this study, we tested the editing efficiencies of four PE6 variants and two additional PE6 constructs with double-RT modules in transgenic rice (Oryza sativa) plants.
View Article and Find Full Text PDFUnlabelled: Cas12a (Cpf1), a Class 2 Type V CRISPR/Cas nuclease, has several unique attributes for genome editing and may provide a valuable alternative to Cas9. However, a low editing efficiency due to temperature sensitivity and insufficient cleavage activity of the Cas12a nuclease are major obstacles to its broad application. In this report, we generated two variants, ttAsCas12 Ultra and ttLbCas12a Ultra harboring three (E174R, M537R, and F870L) or two (D156R and E795L) mutations, respectively, by combining the mutations from the temperature-tolerant variants ttAsCas12a (E174R) and ttLbCas12a (D156R), and those from the highly active variants AsCas12a Ultra (M537R and F870L) and LbCas12a Ultra (E795L).
View Article and Find Full Text PDFPrime editing (PE) technology enables precise alterations in the genetic code of a genome of interest. PE offers great potential for identifying major agronomically important genes in plants and editing them into superior variants, ideally targeting multiple loci simultaneously to realize the collective effects of the edits. Here, we report the development of a modular assembly-based multiplex PE system in rice and demonstrate its efficacy in editing up to four genes in a single transformation experiment.
View Article and Find Full Text PDFUsing genetic resistance against bacterial blight (BB) caused by Xanthomonas oryzae pathovar oryzae (Xoo) is a major objective in rice breeding programmes. Prime editing (PE) has the potential to create novel germplasm against Xoo. Here, we use an improved prime-editing system to implement two new strategies for BB resistance.
View Article and Find Full Text PDFLow efficiency is the main obstacle to using prime editing in maize (Zea mays). Recently, prime-editing efficiency was greatly improved in mammalian cells and rice (Oryza sativa) plants by engineering prime-editing guide RNAs (pegRNAs), optimizing the prime editor (PE) protein, and manipulating cellular determinants of prime editing. In this study, we tested PEs optimized via these three strategies in maize.
View Article and Find Full Text PDFIntroduction: Uremic pruritus is very common in hemodialysis or renal failure patients, there were lots of available treatments such as gabapentin, pregabalin, ondansetron, etc. However, there is no quantified study comparing these treatments together, it is impossible to conduct a clinical trial involving so many treatments, so we conduct a network meta-analysis to compare them.
Method: We collected mean difference and standard error of visual analogue scale data as outcome.
Prime editing is a novel and universal CRISPR/Cas-derived precision genome-editing technology that has been recently developed. However, low efficiency of prime editing has been shown in transgenic rice lines. We hypothesize that enhancing pegRNA expression could improve prime-editing efficiency.
View Article and Find Full Text PDFBackground: The clinical effects and safety over the treatment of tibia intercondylar eminence fracture (TIEF) with cannulated screw and suture fixation were evaluated under arthroscope systematically, providing evidence-based medical support for the selection of surgical methods in terms of minimally invasive arthroscopic treatment for TIEF.
Methods: The English databases of PubMed, EMBASE, Cochrane Library, CNKI, SinoMed, VIP, and Wanfang databases were searched by computer. The randomized controlled trials were conducted to compare the clinical effects of TIEF with cannulated screw and suture fixation under arthroscope.
Lack of appropriate methods for delivery of genome-editing reagents is a major barrier to CRISPR/Cas-mediated genome editing in plants. Agrobacterium-mediated genetic transformation (AMGT) is the preferred method of CRISPR/Cas reagent delivery, and researchers have recently made great improvements to this process. In this article, we review the development of AMGT and AMGT-based delivery of CRISPR/Cas reagents.
View Article and Find Full Text PDFThe lack of efficient delivery methods is a major barrier to clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas)-mediated genome editing in many plant species. Combinations of morphogenic regulator (MR) genes and ternary vector systems are promising solutions to this problem. In this study, we first demonstrated that MR vectors greatly enhance maize () transformation.
View Article and Find Full Text PDFIntroduction: Polygoni Orientalis Fructus (POF) is a clinically effective Chinese medicine. Raw POF (RPOF) and POF Tostus (POFT) are used separately in clinics. However, incomplete progress has been made on quality control.
View Article and Find Full Text PDFOligosaccharide esters, which are among the main active components of Polygalae Radix (PR), demonstrate significant pharmacological activities in the human nervous system. In our previous research, some other constituents in PR were able to improve the bioavailability of oligosaccharide esters such as sibiricose A5 (SA5), sibiricose A6 (SA6), and 3,6'-disinapoyl sucrose (DISS), but the related components and their underlying mechanisms remain unknown. The present study aimed to investigate the intestinal absorptive profile of SA5, SA6, and DISS and the absorptive behavior influenced by the coadministration of polygalaxanthone III and total saponins of PR (TS) using an everted rat gut sac model, along with the possible mechanisms that may influence absorption.
View Article and Find Full Text PDFWe present novel observations of high-specificity SpCas9 variants, sgRNA expression strategies based on mutant sgRNA scaffold and tRNA processing system, and CRISPR/Cas9-mediated T-DNA integrations. Specificity of CRISPR/Cas9 tools has been a major concern along with the reports of their successful applications. We report unexpected observations of high frequency off-target mutagenesis induced by CRISPR/Cas9 in T1 Arabidopsis mutants although the sgRNA was predicted to have a high specificity score.
View Article and Find Full Text PDFEfficient generation of plants carrying mutations in multiple genes remains a challenge. Using two or more orthogonal CRISPR/Cas systems can generate plants with multi-gene mutations, but assembly of these systems requires a robust, high-capacity toolkit. Here, we describe MISSA 2.
View Article and Find Full Text PDFIn the present study, we investigated the effects of hydroxyethyl starch (HES) 130/0.4 on serum pro-inflammatory variables, immunologic variables, fluid balance (FB)-negative(-) rate and renal function in severe acute pancreatitis (SAP) patients. From October, 2007 to November, 2008, a total of 120 SAP patients were enrolled in this retrospective study.
View Article and Find Full Text PDFOrgan abscission is an important plant developmental process that occurs in response to environmental stress or pathogens. In Arabidopsis, ligand signals, such as ethylene or INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), can regulate organ abscission. Previously, we reported that overexpression of AtDOF4.
View Article and Find Full Text PDFJ Huazhong Univ Sci Technolog Med Sci
December 2015
Arabidopsis mutants produced by constitutive overexpression of the CRISPR/Cas9 genome editing system are usually mosaics in the T1 generation. In this study, we used egg cell-specific promoters to drive the expression of Cas9 and obtained non-mosaic T1 mutants for multiple target genes with high efficiency. Comparisons of 12 combinations of eight promoters and two terminators found that the efficiency of the egg cell-specific promoter-controlled CRISPR/Cas9 system depended on the presence of a suitable terminator, and the composite promoter generated by fusing two egg cell-specific promoters resulted in much higher efficiency of mutation in the T1 generation compared with the single promoters.
View Article and Find Full Text PDFBackground: To accelerate the application of the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/ CRISPR-associated protein 9) system to a variety of plant species, a toolkit with additional plant selectable markers, more gRNA modules, and easier methods for the assembly of one or more gRNA expression cassettes is required.
Results: We developed a CRISPR/Cas9 binary vector set based on the pGreen or pCAMBIA backbone, as well as a gRNA (guide RNA) module vector set, as a toolkit for multiplex genome editing in plants. This toolkit requires no restriction enzymes besides BsaI to generate final constructs harboring maize-codon optimized Cas9 and one or more gRNAs with high efficiency in as little as one cloning step.
Background: The aim of this meta-analysis was to compare the long-term survival, mortality, morbidity and the operation-related events in patients with periampullary and pancreatic carcinoma undergoing pylorus-preserving pancreaticoduodenectomy (PPPD) and pylorus-resecting pancreaticoduodenectomy (PRPD).
Method: A systematic search of literature databases (Cochrane Library, PubMed, EMBASE and Web of Science) was performed to identify studies. Outcome measures comparing PPPD versus PRPD for periampullary and pancreatic carcinoma were long-term survival, mortality, morbidity (overall morbidity, delayed gastric emptying [DGE], pancreatic fistula, wound infection, postoperative bleeding, biliary leakage, ascites and gastroenterostomy leakage) and operation related events (hospital stays, operating time, intraoperative blood loss and red blood cell transfusions).
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
February 2013
Objective: To clone and express Plasmodium falciparum erythrocyte membrane protein 1 DBLalpha (PfEMP1-DBLalpha) and three fragments genes, and screen the strongest affinity sequence with the red blood cell surface receptors-heparin or heparin sulfate in the structure of PfEMP1-DBLalpha.
Methods: The sequence of PfEMP1-DBLalpha1245 was optimized according to the characteristics of E. coli codon, synthesized, and divided into three fragments (DBLaA, DBLalphaB, and DBLalphaC) by PCR.
Toxoplasma gondii, a ubiquitous intracellular protozoan, infects one third of the world human population. It is of great medical significance, especially for pregnant women and immune-compromised patients. Accurate and early detection of T.
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