Rabbit defensin (NP-1) genetic engineering of plant

Defensin is a small, cysteine-rich, cationic peptides family with antimicrobial and cytotoxic properties. Among all known defensins, neutrophil peptide-1 (NP-1), which is expressed mainly in rabbit neutrophils, has a broad resistance spectrum to pathogens such as Treponema pallidum, many Grampositive bacteria, Gram-negative bacteria, fungi, viruses. Besides, it has the same striking inhibition or toxic effect on some nausea and tumor cells. Due to the broad antibacterial spectrum and special mechanism of microbial inhibition, rabbit defensin has been transformed into some plants and expressed via genetic engineering. And it plays an important role in genetic engineering of anti-disease plants and plants species’ improvement. This article reviewed and discussed the advantages and research progress of the rabbit defensin genetic engineering of plant in recent years, and also focuses on the existing problems and new strategies in this area.Key words: Rabbit defensin (NP-1), structure, bioactivity, genetic engineering of plant

One-step fabrication of biocompatible chitosan-coated ZnS and ZnS:Mn2+ quantum dots via a γ-radiation route

Biocompatible chitosan-coated ZnS quantum dots [CS-ZnS QDs] and chitosan-coated ZnS:Mn2+ quantum dots [CS-ZnS:Mn2+ QDs] were successfully fabricated via a convenient one-step γ-radiation route. The as-obtained QDs were around 5 nm in diameter with excellent water-solubility. These QDs emitting strong visible blue or orange light under UV excitation were successfully used as labels for PANC-1 cells. The cell experiments revealed that CS-ZnS and CS-ZnS:Mn2+ QDs showed low cytotoxicity and good biocompatibility, which offered possibilities for further biomedical applications. Moreover, this convenient synthesis strategy could be extended to fabricate other nanoparticles coated with chitosan

Electroluminescent Characteristics of DBPPV–ZnO Nanocomposite Polymer Light Emitting Devices

We have demonstrated that fabrication and characterization of nanocomposite polymer light emitting devices with metal Zinc Oxide (ZnO) nanoparticles and 2,3-dibutoxy-1,4-poly(phenylenevinylene) (DBPPV). The current and luminance characteristics of devices with ZnO nanoparticles are much better than those of device with pure DBPPV. Optimized maximum luminance efficiencies of DBPPV–ZnO (3:1 wt%) before annealing (1.78 cd/A) and after annealing (2.45 cd/A) having a brightness 643 and 776 cd/m2at a current density of 36.16 and 31.67 mA/cm2are observed, respectively. Current density–voltage and brightness–voltage characteristics indicate that addition of ZnO nanoparticles can facilitate electrical injection and charge transport. The thermal annealing is thought to result in the formation of an interfacial layer between emissive polymer film and cathode

Facile Phosphine-Free Synthesis of CdSe/ZnS Core/Shell Nanocrystals Without Precursor Injection

A new simple method for synthesis of core/shell CdSe/ZnS nanocrystals (NCs) is present. By adapting the use of cadmium stearate, oleylamine, and paraffin liquid to a non-injection synthesis and by applying a subsequent ZnS shelling procedure to CdSe NCs cores using Zinc acetate dihydrate and sulfur powder, luminescent CdSe/ZnS NCs with quantum yields of up to 36% (FWHM 42–43 nm) were obtained. A seeding-growth technique was first applied to the controlled synthesis of ZnS shell. This method has several attractive features, such as the usage of low-cost, green, and environmentally friendlier reagents and elimination of the need for air-sensitive, toxic, and expensive phosphines solvent. Furthermore, due to one-pot synthetic route for CdSe/ZnS NCs, the approach presented herein is accessible to a mass production of these NCs

DSIF and RNA Polymerase II CTD Phosphorylation Coordinate the Recruitment of Rpd3S to Actively Transcribed Genes

Histone deacetylase Rpd3 is part of two distinct complexes: the large (Rpd3L) and small (Rpd3S) complexes. While Rpd3L targets specific promoters for gene repression, Rpd3S is recruited to ORFs to deacetylate histones in the wake of RNA polymerase II, to prevent cryptic initiation within genes. Methylation of histone H3 at lysine 36 by the Set2 methyltransferase is thought to mediate the recruitment of Rpd3S. Here, we confirm by ChIP–Chip that Rpd3S binds active ORFs. Surprisingly, however, Rpd3S is not recruited to all active genes, and its recruitment is Set2-independent. However, Rpd3S complexes recruited in the absence of H3K36 methylation appear to be inactive. Finally, we present evidence implicating the yeast DSIF complex (Spt4/5) and RNA polymerase II phosphorylation by Kin28 and Ctk1 in the recruitment of Rpd3S to active genes. Taken together, our data support a model where Set2-dependent histone H3 methylation is required for the activation of Rpd3S following its recruitment to the RNA polymerase II C-terminal domain

pH-responsive poly (acrylic acid)-gated mesoporous silica and its application in oral colon targeted drug delivery for doxorubicin

Oral chemotherapy is the preferred route for cancer treatment because it can improve the efficacy and decrease the side effects. Unfortunately, most anticancer drugs suffered from their poor oral bioavailability. Herein, we construct a novel pH-triggered oral drug delivery system by capping of mesoporous silica SBA-15 with pH-responsive polymer poly (acrylic acid) (PAA) via a facile graft-onto strategy. The experiment results demonstrated that the PAA brushes were anchored on the pore outlets of mesoporous silica SBA-15, which can be acted as the gatekeeper to control the drug molecules transport in and out of the pore channels. The PM capped mesoporous SBA-15 (PAA/SBA-15) exhibited a high drug loading capacity (785.7 mg/g), excellent pH-sensitivity and good biocompatibility. In gastric environment (pH=2.0), the drug doxorubicin (DOX) molecules were encapsulated in the pore channels because the pore outlets were capped with collapsed PAA. In contrast, in colonic environment (pH=7.6), it exhibited a fast release because of the removal of capping. In addition, the water solubility of DOX in colonic environment was enhanced after DOX being loaded into the pores of PAA/SBA-15. This pH-triggered oral drug delivery system has promising applications for treatment of colon cancer and other colon diseases.Department of Applied Physics201805 bcr