ABSTRACT
The site-specific recombination systems are composed of recombinases and specific recognition sites, which are powerful tools for gene manipulation and have been extensively used in life sciences research. Inducible recombination systems have been developed to precisely regulate gene expression in a spatiotemporal manner in cells and animals for applications such as gene function research, cell lineage tracing and disease treatment. Based on different spatiotemporal expression methods of recombinases, inducible recombination systems can be divided into two categories: chemical- controlled and light-controlled inductions. Light-controlled inducible recombination systems that utilize light as inducer consist of photocage and optogenetics in accordance with optical control patterns and objects. Photocaged inducible recombination systems are using photosensitive groups to control chemical inducers or recombinases. Their activities are inhibited by photosensitive groups before light induction and recovered after specific light irradiation, leading to light-controlled inducible gene recombination. While optogenetic inducible recombination systems rely on reactivations of split recombinases that mediated by optogenetic switches. Optogenetic switches are composed of a series of gene-encoded photosensitive proteins, including cryptochromes, VIVID, phytochromes, etc. These types of light-controlled inducible recombination systems provide more possibilities for analyzing gene expression and function from the dimension of high spatiotemporal resolution to meet the increasingly complex demands of life science research. In this review, we summarize the developing principles and applications of different types of light-controlled inducible recombination systems, compare their advantages and disadvantages, and prospect the development of more light-controlled recombination systems in the future, with the aims to provide theoretical basis and guidance for system optimization and upgrade.
Subject(s)
Optogenetics , Recombinases , Animals , Optogenetics/methods , Recombinases/metabolism , Recombination, GeneticABSTRACT
ROPs (Rho-like GTPases from plants) belong to the Rho-GTPase subfamily and serve as molecular switches for regulating diverse cellular events, including morphogenesis and stress responses. However, the immune functions of ROPs in Solanum lycopersicum Linn. (tomato) is still largely unclear. The tomato genome contains nine genes encoding ROP-type small GTPase family proteins (namely SlRop1-9) that fall into five distinct groups as revealed by phylogenetic tree. We studied the subcellular localization and immune response induction of nine SlRops by using a transient overexpression system in Nicotiana benthamiana Domin. Except for SlRop1 and SlRop3, which are solely localized at the plasma membrane, most of the remaining ROPs have additional nuclear and/or cytoplasmic distributions. We also revealed that the number of basic residues in the polybasic region of ROPs tends to be correlated with their membrane accumulation. Though nine SlRops are highly conserved at the RHO (Ras Homology) domains, only seven constitutively active forms of SlRops were able to trigger hypersensitive responses. Furthermore, we analyzed the tissue-specific expression patterns of nine ROPs and found that the expression levels of SlRop3, 4 and 6 were generally high in different tissues. The expression levels of SlRop1, 2 and 7 significantly decreased in tomato seedlings after infection with Ralstonia solanacearum (E.F. Smith) Yabuuchi et al. (GMI1000); the others did not respond. Infection assays among nine ROPs showed that SlRop3 and SlRop4 might be positive regulators of tomato bacterial wilt disease resistance, whereas the rest of the ROPs may not contribute to defense. Our study provides systematic evidence of tomato Rho-related small GTPases for localization, immune response, and disease resistance.
Subject(s)
Monomeric GTP-Binding Proteins , Ralstonia solanacearum , Solanum lycopersicum , Disease Resistance/genetics , Solanum lycopersicum/genetics , Solanum lycopersicum/metabolism , Monomeric GTP-Binding Proteins/genetics , Phylogeny , Ralstonia solanacearum/metabolism , rho GTP-Binding Proteins/metabolismABSTRACT
Unwanted biofilms present challenges for many industries. Herein an innovative biofilm removal technology was developed based on nitrite-accelerated Fenton chemistry, where both dissolved Cu ions and nano-CuO surfaces efficiently generate reactive nitrogen species as disinfectants. This simple, efficient, and cost-effective approach for biofilm removal generates important insights into Fenton chemistry, a fundamental mechanism in nature, considering the ubiquity of copper, hydrogen peroxide, and nitrite in the environment, biological systems, and various industrial processes.
Subject(s)
Anti-Bacterial Agents/chemistry , Copper/chemistry , Metal Nanoparticles/chemistry , Nitrites/chemistry , Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Copper/pharmacology , Drug Therapy, Combination , Escherichia coli , Free Radicals/chemistry , Hydrogen Peroxide/chemistry , Nitrites/pharmacology , Staphylococcus aureus , Surface PropertiesABSTRACT
Biofilms present challenges to numerous industries. Herein, a simple approach was developed based on chloride-accelerated Fenton chemistry, where copper oxide nanoparticles facilitate efficient generation of reactive chlorine species for biofilm removal.
Subject(s)
Biofilms , Chlorides/chemistry , Copper/chemistry , Hydrogen Peroxide/chemistry , Iron/chemistry , Nanoparticles/chemistryABSTRACT
The patent information of ultrasound countercurrent extraction used in traditional Chinese medicine was analyzed in this paper by the samples from Derwent World Patent Database (DWPI) and the Chinese Patent Abstracts Database (CNABS). The application of ultrasound countercurrent was discussed with the patent applicant,the amount of the annual distribution, and the pharmaceutical raw materials and other aspects. While the technical parameters published in the patent was deeply analyzed, such as material crushing, extraction solvent, extraction time and temperature, extraction equipment and ultrasonic frequency. Thought above research, various technical parameters of ultrasound countercurrent extraction used in traditional Chinese was summarize. The analysis conclusion of the paper can be used in discovering the technical advantages, optimizing extraction conditions, and providing a reference to extraction technological innovation of traditional Chinese medicine.